diff --git a/harness/decimalToHexString.js b/harness/decimalToHexString.js
new file mode 100644
index 0000000000..36a2bb5b49
--- /dev/null
+++ b/harness/decimalToHexString.js
@@ -0,0 +1,21 @@
+// Copyright (C) 2017 André Bargull. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+
+function decimalToHexString(n) {
+  var hex = "0123456789ABCDEF";
+  n >>>= 0;
+  var s = "";
+  while (n) {
+    s = hex[n & 0xf] + s;
+    n >>>= 4;
+  }
+  while (s.length < 4) {
+    s = "0" + s;
+  }
+  return s;
+}
+
+function decimalToPercentHexString(n) {
+  var hex = "0123456789ABCDEF";
+  return "%" + hex[(n >> 4) & 0xf] + hex[n & 0xf];
+}
diff --git a/test/built-ins/decodeURI/S15.1.3.1_A1.13_T1.js b/test/built-ins/decodeURI/S15.1.3.1_A1.13_T1.js
index a1f9ec4868..d97fc87d9e 100644
--- a/test/built-ins/decodeURI/S15.1.3.1_A1.13_T1.js
+++ b/test/built-ins/decodeURI/S15.1.3.1_A1.13_T1.js
@@ -7,6 +7,7 @@ info: >
     throw URIError
 es5id: 15.1.3.1_A1.13_T1
 description: Complex tests. B = [0xC0 - 0xDF], C = [0x00, 0x7F]
+includes: [decimalToHexString.js]
 ---*/
 
 var errorCount = 0;
@@ -16,12 +17,12 @@ var indexO = 0;
 
 for (var indexB = 0xC0; indexB <= 0xDF; indexB++) {
   count++; 
-  var hexB = decimalToHexString(indexB);  
+  var hexB = decimalToPercentHexString(indexB);
   var result = true;
   for (var indexC = 0x00; indexC <= 0x7F; indexC++) {
-    var hexC = decimalToHexString(indexC);  
+    var hexC = decimalToPercentHexString(indexC);
     try {
-      decodeURI("%" + hexB.substring(2) + "%" + hexC.substring(2));
+      decodeURI(hexB + hexC);
     } catch (e) { 
       if ((e instanceof URIError) === true) continue;                
     }
@@ -60,27 +61,3 @@ if (errorCount > 0) {
   }     
   $ERROR('Total error: ' + errorCount + ' bad Unicode character in ' + count + ' ');
 }
-
-function decimalToHexString(n) {
-  n = Number(n);
-  var h = "";
-  for (var i = 3; i >= 0; i--) {
-    if (n >= Math.pow(16, i)) {
-      var t = Math.floor(n / Math.pow(16, i));
-      n -= t * Math.pow(16, i);
-      if ( t >= 10 ) {
-        if ( t == 10 ) { h += "A"; }
-        if ( t == 11 ) { h += "B"; }
-        if ( t == 12 ) { h += "C"; }
-        if ( t == 13 ) { h += "D"; }
-        if ( t == 14 ) { h += "E"; }
-        if ( t == 15 ) { h += "F"; }
-      } else {
-        h += String(t);
-      }
-    } else {
-      h += "0";
-    }
-  }
-  return h;
-}
diff --git a/test/built-ins/decodeURI/S15.1.3.1_A1.13_T2.js b/test/built-ins/decodeURI/S15.1.3.1_A1.13_T2.js
index f257b6b9e1..62767984b2 100644
--- a/test/built-ins/decodeURI/S15.1.3.1_A1.13_T2.js
+++ b/test/built-ins/decodeURI/S15.1.3.1_A1.13_T2.js
@@ -7,6 +7,7 @@ info: >
     throw URIError
 es5id: 15.1.3.1_A1.13_T2
 description: Complex tests. B = [0xC0 - 0xDF], C = [0xC0, 0xFF]
+includes: [decimalToHexString.js]
 ---*/
 
 var errorCount = 0;
@@ -16,12 +17,12 @@ var indexO = 0;
 
 for (var indexB = 0xC0; indexB <= 0xDF; indexB++) {
   count++; 
-  var hexB = decimalToHexString(indexB);  
+  var hexB = decimalToPercentHexString(indexB);
   var result = true;
   for (var indexC = 0xC0; indexC <= 0xFF; indexC++) {
-    var hexC = decimalToHexString(indexC);  
+    var hexC = decimalToPercentHexString(indexC);
     try {
-      decodeURI("%" + hexB.substring(2) + "%" + hexC.substring(2));
+      decodeURI(hexB + hexC);
     } catch (e) { 
       if ((e instanceof URIError) === true) continue;                
     }
@@ -60,27 +61,3 @@ if (errorCount > 0) {
   }     
   $ERROR('Total error: ' + errorCount + ' bad Unicode character in ' + count + ' ');
 }
-
-function decimalToHexString(n) {
-  n = Number(n);
-  var h = "";
-  for (var i = 3; i >= 0; i--) {
-    if (n >= Math.pow(16, i)) {
-      var t = Math.floor(n / Math.pow(16, i));
-      n -= t * Math.pow(16, i);
-      if ( t >= 10 ) {
-        if ( t == 10 ) { h += "A"; }
-        if ( t == 11 ) { h += "B"; }
-        if ( t == 12 ) { h += "C"; }
-        if ( t == 13 ) { h += "D"; }
-        if ( t == 14 ) { h += "E"; }
-        if ( t == 15 ) { h += "F"; }
-      } else {
-        h += String(t);
-      }
-    } else {
-      h += "0";
-    }
-  }
-  return h;
-}
diff --git a/test/built-ins/decodeURI/S15.1.3.1_A1.14_T1.js b/test/built-ins/decodeURI/S15.1.3.1_A1.14_T1.js
index 8357cea7f0..e63fa0bcab 100644
--- a/test/built-ins/decodeURI/S15.1.3.1_A1.14_T1.js
+++ b/test/built-ins/decodeURI/S15.1.3.1_A1.14_T1.js
@@ -7,6 +7,7 @@ info: >
     throw URIError
 es5id: 15.1.3.1_A1.14_T1
 description: Complex tests. B = [0xE0 - 0xEF], C = [0x00, 0x7F]
+includes: [decimalToHexString.js]
 ---*/
 
 var errorCount = 0;
@@ -16,12 +17,12 @@ var indexO = 0;
 
 for (var indexB = 0xE0; indexB <= 0xEF; indexB++) {
   count++; 
-  var hexB = decimalToHexString(indexB); 
+  var hexB = decimalToPercentHexString(indexB);
   var result = true;
   for (var indexC = 0x00; indexC <= 0x7F; indexC++) {
-    var hexC = decimalToHexString(indexC);  
+    var hexC = decimalToPercentHexString(indexC);
     try {
-      decodeURI("%" + hexB.substring(2) + "%" + hexC.substring(2) + "%A0");
+      decodeURI(hexB + hexC + "%A0");
     } catch (e) { 
       if ((e instanceof URIError) === true) continue;                
     }
@@ -60,27 +61,3 @@ if (errorCount > 0) {
   }     
   $ERROR('Total error: ' + errorCount + ' bad Unicode character in ' + count + ' ');
 }
-
-function decimalToHexString(n) {
-  n = Number(n);
-  var h = "";
-  for (var i = 3; i >= 0; i--) {
-    if (n >= Math.pow(16, i)) {
-      var t = Math.floor(n / Math.pow(16, i));
-      n -= t * Math.pow(16, i);
-      if ( t >= 10 ) {
-        if ( t == 10 ) { h += "A"; }
-        if ( t == 11 ) { h += "B"; }
-        if ( t == 12 ) { h += "C"; }
-        if ( t == 13 ) { h += "D"; }
-        if ( t == 14 ) { h += "E"; }
-        if ( t == 15 ) { h += "F"; }
-      } else {
-        h += String(t);
-      }
-    } else {
-      h += "0";
-    }
-  }
-  return h;
-}
diff --git a/test/built-ins/decodeURI/S15.1.3.1_A1.14_T2.js b/test/built-ins/decodeURI/S15.1.3.1_A1.14_T2.js
index 23c4d5f509..35b721e83e 100644
--- a/test/built-ins/decodeURI/S15.1.3.1_A1.14_T2.js
+++ b/test/built-ins/decodeURI/S15.1.3.1_A1.14_T2.js
@@ -7,6 +7,7 @@ info: >
     throw URIError
 es5id: 15.1.3.1_A1.14_T2
 description: Complex tests. B = [0xE0 - 0xEF], C = [0x00, 0x7F]
+includes: [decimalToHexString.js]
 ---*/
 
 var errorCount = 0;
@@ -16,12 +17,12 @@ var indexO = 0;
 
 for (var indexB = 0xE0; indexB <= 0xEF; indexB++) {
   count++; 
-  var hexB = decimalToHexString(indexB);  
+  var hexB = decimalToPercentHexString(indexB);
   var result = true;
   for (var indexC = 0x00; indexC <= 0x7F; indexC++) {
-    var hexC = decimalToHexString(indexC);  
+    var hexC = decimalToPercentHexString(indexC);
     try {
-      decodeURI("%" + hexB.substring(2) + "%A0" + "%" + hexC.substring(2));
+      decodeURI(hexB + "%A0" + hexC);
     } catch (e) { 
       if ((e instanceof URIError) === true) continue;                
     }
@@ -60,27 +61,3 @@ if (errorCount > 0) {
   }     
   $ERROR('Total error: ' + errorCount + ' bad Unicode character in ' + count + ' ');
 }
-
-function decimalToHexString(n) {
-  n = Number(n);
-  var h = "";
-  for (var i = 3; i >= 0; i--) {
-    if (n >= Math.pow(16, i)) {
-      var t = Math.floor(n / Math.pow(16, i));
-      n -= t * Math.pow(16, i);
-      if ( t >= 10 ) {
-        if ( t == 10 ) { h += "A"; }
-        if ( t == 11 ) { h += "B"; }
-        if ( t == 12 ) { h += "C"; }
-        if ( t == 13 ) { h += "D"; }
-        if ( t == 14 ) { h += "E"; }
-        if ( t == 15 ) { h += "F"; }
-      } else {
-        h += String(t);
-      }
-    } else {
-      h += "0";
-    }
-  }
-  return h;
-}
diff --git a/test/built-ins/decodeURI/S15.1.3.1_A1.14_T3.js b/test/built-ins/decodeURI/S15.1.3.1_A1.14_T3.js
index d69fdab9d9..c3c6e6c1fb 100644
--- a/test/built-ins/decodeURI/S15.1.3.1_A1.14_T3.js
+++ b/test/built-ins/decodeURI/S15.1.3.1_A1.14_T3.js
@@ -7,6 +7,7 @@ info: >
     throw URIError
 es5id: 15.1.3.1_A1.14_T3
 description: Complex tests. B = [0xE0 - 0xEF], C = [0xC0, 0xFF]
+includes: [decimalToHexString.js]
 ---*/
 
 var errorCount = 0;
@@ -16,12 +17,12 @@ var indexO = 0;
 
 for (var indexB = 0xE0; indexB <= 0xEF; indexB++) {
   count++; 
-  var hexB = decimalToHexString(indexB); 
+  var hexB = decimalToPercentHexString(indexB);
   var result = true;
   for (var indexC = 0xC0; indexC <= 0xFF; indexC++) {
-    var hexC = decimalToHexString(indexC);  
+    var hexC = decimalToPercentHexString(indexC);
     try {
-      decodeURI("%" + hexB.substring(2) + "%" + hexC.substring(2) + "%A0");
+      decodeURI(hexB + hexC + "%A0");
     } catch (e) { 
       if ((e instanceof URIError) === true) continue;                
     }
@@ -60,27 +61,3 @@ if (errorCount > 0) {
   }     
   $ERROR('Total error: ' + errorCount + ' bad Unicode character in ' + count + ' ');
 }
-
-function decimalToHexString(n) {
-  n = Number(n);
-  var h = "";
-  for (var i = 3; i >= 0; i--) {
-    if (n >= Math.pow(16, i)) {
-      var t = Math.floor(n / Math.pow(16, i));
-      n -= t * Math.pow(16, i);
-      if ( t >= 10 ) {
-        if ( t == 10 ) { h += "A"; }
-        if ( t == 11 ) { h += "B"; }
-        if ( t == 12 ) { h += "C"; }
-        if ( t == 13 ) { h += "D"; }
-        if ( t == 14 ) { h += "E"; }
-        if ( t == 15 ) { h += "F"; }
-      } else {
-        h += String(t);
-      }
-    } else {
-      h += "0";
-    }
-  }
-  return h;
-}
diff --git a/test/built-ins/decodeURI/S15.1.3.1_A1.14_T4.js b/test/built-ins/decodeURI/S15.1.3.1_A1.14_T4.js
index 2946136d76..eca2066287 100644
--- a/test/built-ins/decodeURI/S15.1.3.1_A1.14_T4.js
+++ b/test/built-ins/decodeURI/S15.1.3.1_A1.14_T4.js
@@ -7,6 +7,7 @@ info: >
     throw URIError
 es5id: 15.1.3.1_A1.14_T4
 description: Complex tests. B = [0xE0 - 0xEF], C = [0xC0, 0xFF]
+includes: [decimalToHexString.js]
 ---*/
 
 var errorCount = 0;
@@ -16,12 +17,12 @@ var indexO = 0;
 
 for (var indexB = 0xE0; indexB <= 0xEF; indexB++) {
   count++; 
-  var hexB = decimalToHexString(indexB);  
+  var hexB = decimalToPercentHexString(indexB);
   var result = true;
   for (var indexC = 0xC0; indexC <= 0xFF; indexC++) {
-    var hexC = decimalToHexString(indexC);  
+    var hexC = decimalToPercentHexString(indexC);
     try {
-      decodeURI("%" + hexB.substring(2) + "%A0" + "%" + hexC.substring(2));
+      decodeURI(hexB + "%A0" + hexC);
     } catch (e) { 
       if ((e instanceof URIError) === true) continue;                
     }
@@ -60,27 +61,3 @@ if (errorCount > 0) {
   }     
   $ERROR('Total error: ' + errorCount + ' bad Unicode character in ' + count + ' ');
 }
-
-function decimalToHexString(n) {
-  n = Number(n);
-  var h = "";
-  for (var i = 3; i >= 0; i--) {
-    if (n >= Math.pow(16, i)) {
-      var t = Math.floor(n / Math.pow(16, i));
-      n -= t * Math.pow(16, i);
-      if ( t >= 10 ) {
-        if ( t == 10 ) { h += "A"; }
-        if ( t == 11 ) { h += "B"; }
-        if ( t == 12 ) { h += "C"; }
-        if ( t == 13 ) { h += "D"; }
-        if ( t == 14 ) { h += "E"; }
-        if ( t == 15 ) { h += "F"; }
-      } else {
-        h += String(t);
-      }
-    } else {
-      h += "0";
-    }
-  }
-  return h;
-}
diff --git a/test/built-ins/decodeURI/S15.1.3.1_A1.15_T1.js b/test/built-ins/decodeURI/S15.1.3.1_A1.15_T1.js
index ad1febe2f7..7eb031a2ef 100644
--- a/test/built-ins/decodeURI/S15.1.3.1_A1.15_T1.js
+++ b/test/built-ins/decodeURI/S15.1.3.1_A1.15_T1.js
@@ -7,6 +7,7 @@ info: >
     throw URIError
 es5id: 15.1.3.1_A1.15_T1
 description: Complex tests. B = [0xF0 - 0x0F7], C = [0x00, 0x7F]
+includes: [decimalToHexString.js]
 ---*/
 
 var errorCount = 0;
@@ -16,12 +17,12 @@ var indexO = 0;
 
 for (var indexB = 0xF0; indexB <= 0xF7; indexB++) {
   count++; 
-  var hexB = decimalToHexString(indexB); 
+  var hexB = decimalToPercentHexString(indexB);
   var result = true;
   for (var indexC = 0x00; indexC <= 0x7F; indexC++) {
-    var hexC = decimalToHexString(indexC);  
+    var hexC = decimalToPercentHexString(indexC);
     try {
-      decodeURI("%" + hexB.substring(2) + "%" + hexC.substring(2) + "%A0%A0");
+      decodeURI(hexB + hexC + "%A0%A0");
     } catch (e) { 
       if ((e instanceof URIError) === true) continue;                
     }
@@ -60,27 +61,3 @@ if (errorCount > 0) {
   }     
   $ERROR('Total error: ' + errorCount + ' bad Unicode character in ' + count + ' ');
 }
-
-function decimalToHexString(n) {
-  n = Number(n);
-  var h = "";
-  for (var i = 3; i >= 0; i--) {
-    if (n >= Math.pow(16, i)) {
-      var t = Math.floor(n / Math.pow(16, i));
-      n -= t * Math.pow(16, i);
-      if ( t >= 10 ) {
-        if ( t == 10 ) { h += "A"; }
-        if ( t == 11 ) { h += "B"; }
-        if ( t == 12 ) { h += "C"; }
-        if ( t == 13 ) { h += "D"; }
-        if ( t == 14 ) { h += "E"; }
-        if ( t == 15 ) { h += "F"; }
-      } else {
-        h += String(t);
-      }
-    } else {
-      h += "0";
-    }
-  }
-  return h;
-}
diff --git a/test/built-ins/decodeURI/S15.1.3.1_A1.15_T2.js b/test/built-ins/decodeURI/S15.1.3.1_A1.15_T2.js
index 401a388206..ac8a83160f 100644
--- a/test/built-ins/decodeURI/S15.1.3.1_A1.15_T2.js
+++ b/test/built-ins/decodeURI/S15.1.3.1_A1.15_T2.js
@@ -7,6 +7,7 @@ info: >
     throw URIError
 es5id: 15.1.3.1_A1.15_T2
 description: Complex tests. B = [0xF0 - 0x0F7], C = [0x00, 0x7F]
+includes: [decimalToHexString.js]
 ---*/
 
 var errorCount = 0;
@@ -16,12 +17,12 @@ var indexO = 0;
 
 for (var indexB = 0xF0; indexB <= 0xF7; indexB++) {
   count++; 
-  var hexB = decimalToHexString(indexB); 
+  var hexB = decimalToPercentHexString(indexB);
   var result = true;
   for (var indexC = 0x00; indexC <= 0x7F; indexC++) {
-    var hexC = decimalToHexString(indexC);  
+    var hexC = decimalToPercentHexString(indexC);
     try {
-      decodeURI("%" + hexB.substring(2) + "%A0" + "%" + hexC.substring(2) + "%A0");
+      decodeURI(hexB + "%A0" + hexC + "%A0");
     } catch (e) { 
       if ((e instanceof URIError) === true) continue;                
     }
@@ -60,27 +61,3 @@ if (errorCount > 0) {
   }     
   $ERROR('Total error: ' + errorCount + ' bad Unicode character in ' + count + ' ');
 }
-
-function decimalToHexString(n) {
-  n = Number(n);
-  var h = "";
-  for (var i = 3; i >= 0; i--) {
-    if (n >= Math.pow(16, i)) {
-      var t = Math.floor(n / Math.pow(16, i));
-      n -= t * Math.pow(16, i);
-      if ( t >= 10 ) {
-        if ( t == 10 ) { h += "A"; }
-        if ( t == 11 ) { h += "B"; }
-        if ( t == 12 ) { h += "C"; }
-        if ( t == 13 ) { h += "D"; }
-        if ( t == 14 ) { h += "E"; }
-        if ( t == 15 ) { h += "F"; }
-      } else {
-        h += String(t);
-      }
-    } else {
-      h += "0";
-    }
-  }
-  return h;
-}
diff --git a/test/built-ins/decodeURI/S15.1.3.1_A1.15_T3.js b/test/built-ins/decodeURI/S15.1.3.1_A1.15_T3.js
index 84ba141934..25e23d51e5 100644
--- a/test/built-ins/decodeURI/S15.1.3.1_A1.15_T3.js
+++ b/test/built-ins/decodeURI/S15.1.3.1_A1.15_T3.js
@@ -7,6 +7,7 @@ info: >
     throw URIError
 es5id: 15.1.3.1_A1.15_T3
 description: Complex tests. B = [0xF0 - 0x0F7], C = [0x00, 0x7F]
+includes: [decimalToHexString.js]
 ---*/
 
 var errorCount = 0;
@@ -16,12 +17,12 @@ var indexO = 0;
 
 for (var indexB = 0xF0; indexB <= 0xF7; indexB++) {
   count++; 
-  var hexB = decimalToHexString(indexB); 
+  var hexB = decimalToPercentHexString(indexB);
   var result = true;
   for (var indexC = 0x00; indexC <= 0x7F; indexC++) {
-    var hexC = decimalToHexString(indexC);  
+    var hexC = decimalToPercentHexString(indexC);
     try {
-      decodeURI("%" + hexB.substring(2) + "%A0%A0" + "%" + hexC.substring(2));
+      decodeURI(hexB + "%A0%A0" + hexC);
     } catch (e) { 
       if ((e instanceof URIError) === true) continue;                
     }
@@ -60,27 +61,3 @@ if (errorCount > 0) {
   }     
   $ERROR('Total error: ' + errorCount + ' bad Unicode character in ' + count + ' ');
 }
-
-function decimalToHexString(n) {
-  n = Number(n);
-  var h = "";
-  for (var i = 3; i >= 0; i--) {
-    if (n >= Math.pow(16, i)) {
-      var t = Math.floor(n / Math.pow(16, i));
-      n -= t * Math.pow(16, i);
-      if ( t >= 10 ) {
-        if ( t == 10 ) { h += "A"; }
-        if ( t == 11 ) { h += "B"; }
-        if ( t == 12 ) { h += "C"; }
-        if ( t == 13 ) { h += "D"; }
-        if ( t == 14 ) { h += "E"; }
-        if ( t == 15 ) { h += "F"; }
-      } else {
-        h += String(t);
-      }
-    } else {
-      h += "0";
-    }
-  }
-  return h;
-}
diff --git a/test/built-ins/decodeURI/S15.1.3.1_A1.15_T4.js b/test/built-ins/decodeURI/S15.1.3.1_A1.15_T4.js
index 839911bfef..83b84fe685 100644
--- a/test/built-ins/decodeURI/S15.1.3.1_A1.15_T4.js
+++ b/test/built-ins/decodeURI/S15.1.3.1_A1.15_T4.js
@@ -7,6 +7,7 @@ info: >
     throw URIError
 es5id: 15.1.3.1_A1.15_T4
 description: Complex tests. B = [0xF0 - 0x0F7], C = [0xC0, 0xFF]
+includes: [decimalToHexString.js]
 ---*/
 
 var errorCount = 0;
@@ -16,12 +17,12 @@ var indexO = 0;
 
 for (var indexB = 0xF0; indexB <= 0xF7; indexB++) {
   count++; 
-  var hexB = decimalToHexString(indexB); 
+  var hexB = decimalToPercentHexString(indexB);
   var result = true;
   for (var indexC = 0xC0; indexC <= 0xFF; indexC++) {
-    var hexC = decimalToHexString(indexC);  
+    var hexC = decimalToPercentHexString(indexC);
     try {
-      decodeURI("%" + hexB.substring(2) + "%" + hexC.substring(2) + "%A0%A0");
+      decodeURI(hexB + hexC + "%A0%A0");
     } catch (e) { 
       if ((e instanceof URIError) === true) continue;                
     }
@@ -60,27 +61,3 @@ if (errorCount > 0) {
   }     
   $ERROR('Total error: ' + errorCount + ' bad Unicode character in ' + count + ' ');
 }
-
-function decimalToHexString(n) {
-  n = Number(n);
-  var h = "";
-  for (var i = 3; i >= 0; i--) {
-    if (n >= Math.pow(16, i)) {
-      var t = Math.floor(n / Math.pow(16, i));
-      n -= t * Math.pow(16, i);
-      if ( t >= 10 ) {
-        if ( t == 10 ) { h += "A"; }
-        if ( t == 11 ) { h += "B"; }
-        if ( t == 12 ) { h += "C"; }
-        if ( t == 13 ) { h += "D"; }
-        if ( t == 14 ) { h += "E"; }
-        if ( t == 15 ) { h += "F"; }
-      } else {
-        h += String(t);
-      }
-    } else {
-      h += "0";
-    }
-  }
-  return h;
-}
diff --git a/test/built-ins/decodeURI/S15.1.3.1_A1.15_T5.js b/test/built-ins/decodeURI/S15.1.3.1_A1.15_T5.js
index 11dc028433..caad3a8b45 100644
--- a/test/built-ins/decodeURI/S15.1.3.1_A1.15_T5.js
+++ b/test/built-ins/decodeURI/S15.1.3.1_A1.15_T5.js
@@ -7,6 +7,7 @@ info: >
     throw URIError
 es5id: 15.1.3.1_A1.15_T5
 description: Complex tests. B = [0xF0 - 0x0F7], C = [0xC0, 0xFF]
+includes: [decimalToHexString.js]
 ---*/
 
 var errorCount = 0;
@@ -16,12 +17,12 @@ var indexO = 0;
 
 for (var indexB = 0xF0; indexB <= 0xF7; indexB++) {
   count++; 
-  var hexB = decimalToHexString(indexB); 
+  var hexB = decimalToPercentHexString(indexB);
   var result = true;
   for (var indexC = 0xC0; indexC <= 0xFF; indexC++) {
-    var hexC = decimalToHexString(indexC);  
+    var hexC = decimalToPercentHexString(indexC);
     try {
-      decodeURI("%" + hexB.substring(2) + "%A0" + "%" + hexC.substring(2) + "%A0");
+      decodeURI(hexB + "%A0" + hexC + "%A0");
     } catch (e) { 
       if ((e instanceof URIError) === true) continue;                
     }
@@ -60,27 +61,3 @@ if (errorCount > 0) {
   }     
   $ERROR('Total error: ' + errorCount + ' bad Unicode character in ' + count + ' ');
 }
-
-function decimalToHexString(n) {
-  n = Number(n);
-  var h = "";
-  for (var i = 3; i >= 0; i--) {
-    if (n >= Math.pow(16, i)) {
-      var t = Math.floor(n / Math.pow(16, i));
-      n -= t * Math.pow(16, i);
-      if ( t >= 10 ) {
-        if ( t == 10 ) { h += "A"; }
-        if ( t == 11 ) { h += "B"; }
-        if ( t == 12 ) { h += "C"; }
-        if ( t == 13 ) { h += "D"; }
-        if ( t == 14 ) { h += "E"; }
-        if ( t == 15 ) { h += "F"; }
-      } else {
-        h += String(t);
-      }
-    } else {
-      h += "0";
-    }
-  }
-  return h;
-}
diff --git a/test/built-ins/decodeURI/S15.1.3.1_A1.15_T6.js b/test/built-ins/decodeURI/S15.1.3.1_A1.15_T6.js
index 50eaff52c0..5fa20665c7 100644
--- a/test/built-ins/decodeURI/S15.1.3.1_A1.15_T6.js
+++ b/test/built-ins/decodeURI/S15.1.3.1_A1.15_T6.js
@@ -7,6 +7,7 @@ info: >
     throw URIError
 es5id: 15.1.3.1_A1.15_T6
 description: Complex tests. B = [0xF0 - 0x0F7], C = [0xC0, 0xFF]
+includes: [decimalToHexString.js]
 ---*/
 
 var errorCount = 0;
@@ -16,12 +17,12 @@ var indexO = 0;
 
 for (var indexB = 0xF0; indexB <= 0xF7; indexB++) {
   count++; 
-  var hexB = decimalToHexString(indexB); 
+  var hexB = decimalToPercentHexString(indexB);
   var result = true;
   for (var indexC = 0xC0; indexC <= 0xFF; indexC++) {
-    var hexC = decimalToHexString(indexC);  
+    var hexC = decimalToPercentHexString(indexC);
     try {
-      decodeURI("%" + hexB.substring(2) + "%A0%A0" + "%" + hexC.substring(2));
+      decodeURI(hexB + "%A0%A0" + hexC);
     } catch (e) { 
       if ((e instanceof URIError) === true) continue;                
     }
@@ -60,27 +61,3 @@ if (errorCount > 0) {
   }     
   $ERROR('Total error: ' + errorCount + ' bad Unicode character in ' + count + ' ');
 }
-
-function decimalToHexString(n) {
-  n = Number(n);
-  var h = "";
-  for (var i = 3; i >= 0; i--) {
-    if (n >= Math.pow(16, i)) {
-      var t = Math.floor(n / Math.pow(16, i));
-      n -= t * Math.pow(16, i);
-      if ( t >= 10 ) {
-        if ( t == 10 ) { h += "A"; }
-        if ( t == 11 ) { h += "B"; }
-        if ( t == 12 ) { h += "C"; }
-        if ( t == 13 ) { h += "D"; }
-        if ( t == 14 ) { h += "E"; }
-        if ( t == 15 ) { h += "F"; }
-      } else {
-        h += String(t);
-      }
-    } else {
-      h += "0";
-    }
-  }
-  return h;
-}
diff --git a/test/built-ins/decodeURI/S15.1.3.1_A1.3_T1.js b/test/built-ins/decodeURI/S15.1.3.1_A1.3_T1.js
index 7125c02a75..636c05160e 100644
--- a/test/built-ins/decodeURI/S15.1.3.1_A1.3_T1.js
+++ b/test/built-ins/decodeURI/S15.1.3.1_A1.3_T1.js
@@ -5,6 +5,7 @@
 info: If B = 10xxxxxx or B = 11111xxx, throw URIError
 es5id: 15.1.3.1_A1.3_T1
 description: Complex tests. B = 10xxxxxx -> B in [0x80 - 0xBF]
+includes: [decimalToHexString.js]
 ---*/
 
 var errorCount = 0;
@@ -14,9 +15,9 @@ var indexO = 0;
 
 for (var index = 0x80; index <= 0xBF; index++) {
   count++; 
-  var hex = decimalToHexString(index);
+  var hex = decimalToPercentHexString(index);
   try {
-    decodeURI("%" + hex.substring(2));
+    decodeURI(hex);
   } catch (e) { 
     if ((e instanceof URIError) === true) continue;                
   }
@@ -51,27 +52,3 @@ if (errorCount > 0) {
   }     
   $ERROR('Total error: ' + errorCount + ' bad Unicode character in ' + count + ' ');
 }
-
-function decimalToHexString(n) {
-  n = Number(n);
-  var h = "";
-  for (var i = 3; i >= 0; i--) {
-    if (n >= Math.pow(16, i)) {
-      var t = Math.floor(n / Math.pow(16, i));
-      n -= t * Math.pow(16, i);
-      if ( t >= 10 ) {
-        if ( t == 10 ) { h += "A"; }
-        if ( t == 11 ) { h += "B"; }
-        if ( t == 12 ) { h += "C"; }
-        if ( t == 13 ) { h += "D"; }
-        if ( t == 14 ) { h += "E"; }
-        if ( t == 15 ) { h += "F"; }
-      } else {
-        h += String(t);
-      }
-    } else {
-      h += "0";
-    }
-  }
-  return h;
-}
diff --git a/test/built-ins/decodeURI/S15.1.3.1_A1.3_T2.js b/test/built-ins/decodeURI/S15.1.3.1_A1.3_T2.js
index 1a154784b7..a00a58dea2 100644
--- a/test/built-ins/decodeURI/S15.1.3.1_A1.3_T2.js
+++ b/test/built-ins/decodeURI/S15.1.3.1_A1.3_T2.js
@@ -5,6 +5,7 @@
 info: If B = 10xxxxxx or B = 11111xxx, throw URIError
 es5id: 15.1.3.1_A1.3_T2
 description: Complex tests. B = 11111xxx -> B in [0xF8 - 0xFF]
+includes: [decimalToHexString.js]
 ---*/
 
 var errorCount = 0;
@@ -14,9 +15,9 @@ var indexO = 0;
 
 for (var index = 0xF8; index <= 0xFF; index++) {
   count++; 
-  var hex = decimalToHexString(index);
+  var hex = decimalToPercentHexString(index);
   try {
-    decodeURI("%" + hex.substring(2));
+    decodeURI(hex);
   } catch (e) { 
     if ((e instanceof URIError) === true) continue;                
   }
@@ -51,27 +52,3 @@ if (errorCount > 0) {
   }     
   $ERROR('Total error: ' + errorCount + ' bad Unicode character in ' + count + ' ');
 }
-
-function decimalToHexString(n) {
-  n = Number(n);
-  var h = "";
-  for (var i = 3; i >= 0; i--) {
-    if (n >= Math.pow(16, i)) {
-      var t = Math.floor(n / Math.pow(16, i));
-      n -= t * Math.pow(16, i);
-      if ( t >= 10 ) {
-        if ( t == 10 ) { h += "A"; }
-        if ( t == 11 ) { h += "B"; }
-        if ( t == 12 ) { h += "C"; }
-        if ( t == 13 ) { h += "D"; }
-        if ( t == 14 ) { h += "E"; }
-        if ( t == 15 ) { h += "F"; }
-      } else {
-        h += String(t);
-      }
-    } else {
-      h += "0";
-    }
-  }
-  return h;
-}
diff --git a/test/built-ins/decodeURI/S15.1.3.1_A1.4_T1.js b/test/built-ins/decodeURI/S15.1.3.1_A1.4_T1.js
index 6a80cd17ab..5bc6fc1043 100644
--- a/test/built-ins/decodeURI/S15.1.3.1_A1.4_T1.js
+++ b/test/built-ins/decodeURI/S15.1.3.1_A1.4_T1.js
@@ -5,6 +5,7 @@
 info: If B = 110xxxxx (n = 2) and (k + 2) + 3 >= length, throw URIError
 es5id: 15.1.3.1_A1.4_T1
 description: Complex tests. B = [0xC0 - 0xDF]
+includes: [decimalToHexString.js]
 ---*/
 
 var errorCount = 0;
@@ -17,9 +18,9 @@ for (var index = 0xC0; index <= 0xDF; index++) {
   var str = "";
   var result = true;
   for (var len = 0; len < 3; len++) {
-    var hex = decimalToHexString(index);
+    var hex = decimalToPercentHexString(index);
     try {
-      decodeURI("%" + hex.substring(2) + str);      
+      decodeURI(hex + str);
     } catch (e) { 
       if ((e instanceof URIError) === true) continue;                
     }
@@ -59,27 +60,3 @@ if (errorCount > 0) {
   }     
   $ERROR('Total error: ' + errorCount + ' bad Unicode character in ' + count + ' ');
 }
-
-function decimalToHexString(n) {
-  n = Number(n);
-  var h = "";
-  for (var i = 3; i >= 0; i--) {
-    if (n >= Math.pow(16, i)) {
-      var t = Math.floor(n / Math.pow(16, i));
-      n -= t * Math.pow(16, i);
-      if ( t >= 10 ) {
-        if ( t == 10 ) { h += "A"; }
-        if ( t == 11 ) { h += "B"; }
-        if ( t == 12 ) { h += "C"; }
-        if ( t == 13 ) { h += "D"; }
-        if ( t == 14 ) { h += "E"; }
-        if ( t == 15 ) { h += "F"; }
-      } else {
-        h += String(t);
-      }
-    } else {
-      h += "0";
-    }
-  }
-  return h;
-}
diff --git a/test/built-ins/decodeURI/S15.1.3.1_A1.5_T1.js b/test/built-ins/decodeURI/S15.1.3.1_A1.5_T1.js
index a8758ef18b..a6ed0d021f 100644
--- a/test/built-ins/decodeURI/S15.1.3.1_A1.5_T1.js
+++ b/test/built-ins/decodeURI/S15.1.3.1_A1.5_T1.js
@@ -5,6 +5,7 @@
 info: If B = 1110xxxx (n = 3) and (k + 2) + 6 >= length, throw URIError
 es5id: 15.1.3.1_A1.5_T1
 description: Complex tests. B = [0xE0 - 0xEF]
+includes: [decimalToHexString.js]
 ---*/
 
 var errorCount = 0;
@@ -17,9 +18,9 @@ for (var index = 0xE0; index <= 0xEF; index++) {
   var str = "";
   var result = true;
   for (var len = 0; len < 6; len++) {
-    var hex = decimalToHexString(index);
+    var hex = decimalToPercentHexString(index);
     try {
-      decodeURI("%" + hex.substring(2) + str);      
+      decodeURI(hex + str);
     } catch (e) { 
       if ((e instanceof URIError) === true) continue;                
     }
@@ -59,27 +60,3 @@ if (errorCount > 0) {
   }     
   $ERROR('Total error: ' + errorCount + ' bad Unicode character in ' + count + ' ');
 }
-
-function decimalToHexString(n) {
-  n = Number(n);
-  var h = "";
-  for (var i = 3; i >= 0; i--) {
-    if (n >= Math.pow(16, i)) {
-      var t = Math.floor(n / Math.pow(16, i));
-      n -= t * Math.pow(16, i);
-      if ( t >= 10 ) {
-        if ( t == 10 ) { h += "A"; }
-        if ( t == 11 ) { h += "B"; }
-        if ( t == 12 ) { h += "C"; }
-        if ( t == 13 ) { h += "D"; }
-        if ( t == 14 ) { h += "E"; }
-        if ( t == 15 ) { h += "F"; }
-      } else {
-        h += String(t);
-      }
-    } else {
-      h += "0";
-    }
-  }
-  return h;
-}
diff --git a/test/built-ins/decodeURI/S15.1.3.1_A1.6_T1.js b/test/built-ins/decodeURI/S15.1.3.1_A1.6_T1.js
index 3f8347af2d..fcdc4c821b 100644
--- a/test/built-ins/decodeURI/S15.1.3.1_A1.6_T1.js
+++ b/test/built-ins/decodeURI/S15.1.3.1_A1.6_T1.js
@@ -5,6 +5,7 @@
 info: If B = 11110xxx (n = 4) and (k + 2) + 9 >= length, throw URIError
 es5id: 15.1.3.1_A1.6_T1
 description: Complex tests. B = [0xF0 - 0xF7]
+includes: [decimalToHexString.js]
 ---*/
 
 var errorCount = 0;
@@ -17,9 +18,9 @@ for (var index = 0xF0; index <= 0xF7; index++) {
   var str = "";
   var result = true;
   for (var len = 0; len < 9; len++) {
-    var hex = decimalToHexString(index);
+    var hex = decimalToPercentHexString(index);
     try {
-      decodeURI("%" + hex.substring(2) + str);      
+      decodeURI(hex + str);
     } catch (e) { 
       if ((e instanceof URIError) === true) continue;                
     }
@@ -59,27 +60,3 @@ if (errorCount > 0) {
   }     
   $ERROR('Total error: ' + errorCount + ' bad Unicode character in ' + count + ' ');
 }
-
-function decimalToHexString(n) {
-  n = Number(n);
-  var h = "";
-  for (var i = 3; i >= 0; i--) {
-    if (n >= Math.pow(16, i)) {
-      var t = Math.floor(n / Math.pow(16, i));
-      n -= t * Math.pow(16, i);
-      if ( t >= 10 ) {
-        if ( t == 10 ) { h += "A"; }
-        if ( t == 11 ) { h += "B"; }
-        if ( t == 12 ) { h += "C"; }
-        if ( t == 13 ) { h += "D"; }
-        if ( t == 14 ) { h += "E"; }
-        if ( t == 15 ) { h += "F"; }
-      } else {
-        h += String(t);
-      }
-    } else {
-      h += "0";
-    }
-  }
-  return h;
-}
diff --git a/test/built-ins/decodeURI/S15.1.3.1_A1.7_T1.js b/test/built-ins/decodeURI/S15.1.3.1_A1.7_T1.js
index 3d3b5035e1..502fb1edfd 100644
--- a/test/built-ins/decodeURI/S15.1.3.1_A1.7_T1.js
+++ b/test/built-ins/decodeURI/S15.1.3.1_A1.7_T1.js
@@ -7,6 +7,7 @@ info: >
     URIError
 es5id: 15.1.3.1_A1.7_T1
 description: Complex tests. B = [0xC0 - 0xDF]
+includes: [decimalToHexString.js]
 ---*/
 
 var errorCount = 0;
@@ -16,9 +17,9 @@ var indexO = 0;
 
 for (var index = 0xC0; index <= 0xDF; index++) {
   count++; 
-  var hex = decimalToHexString(index);
+  var hex = decimalToPercentHexString(index);
   try {
-    decodeURI("%" + hex.substring(2) + "111");
+    decodeURI(hex + "111");
   } catch (e) { 
     if ((e instanceof URIError) === true) continue;                
   }
@@ -53,27 +54,3 @@ if (errorCount > 0) {
   }     
   $ERROR('Total error: ' + errorCount + ' bad Unicode character in ' + count + ' ');
 }
-
-function decimalToHexString(n) {
-  n = Number(n);
-  var h = "";
-  for (var i = 3; i >= 0; i--) {
-    if (n >= Math.pow(16, i)) {
-      var t = Math.floor(n / Math.pow(16, i));
-      n -= t * Math.pow(16, i);
-      if ( t >= 10 ) {
-        if ( t == 10 ) { h += "A"; }
-        if ( t == 11 ) { h += "B"; }
-        if ( t == 12 ) { h += "C"; }
-        if ( t == 13 ) { h += "D"; }
-        if ( t == 14 ) { h += "E"; }
-        if ( t == 15 ) { h += "F"; }
-      } else {
-        h += String(t);
-      }
-    } else {
-      h += "0";
-    }
-  }
-  return h;
-}
diff --git a/test/built-ins/decodeURI/S15.1.3.1_A1.8_T1.js b/test/built-ins/decodeURI/S15.1.3.1_A1.8_T1.js
index 387cf52f70..85d6657f21 100644
--- a/test/built-ins/decodeURI/S15.1.3.1_A1.8_T1.js
+++ b/test/built-ins/decodeURI/S15.1.3.1_A1.8_T1.js
@@ -7,8 +7,8 @@ info: >
     string.charAt(k + 6) not equal "%", throw URIError
 es5id: 15.1.3.1_A1.8_T1
 description: >
-    Complex tests. B = [0xE0 - 0xEF],  string.charAt(k + 3) not equal
-    "%"
+    Complex tests. B = [0xE0 - 0xEF],  string.charAt(k + 3) not equal "%"
+includes: [decimalToHexString.js]
 ---*/
 
 var errorCount = 0;
@@ -18,9 +18,9 @@ var indexO = 0;
 
 for (var index = 0xE0; index <= 0xEF; index++) {
   count++; 
-  var hex = decimalToHexString(index);
+  var hex = decimalToPercentHexString(index);
   try {
-    decodeURI("%" + hex.substring(2) + "111%A0");
+    decodeURI(hex + "111%A0");
   } catch (e) { 
     if ((e instanceof URIError) === true) continue;                
   }
@@ -55,27 +55,3 @@ if (errorCount > 0) {
   }     
   $ERROR('Total error: ' + errorCount + ' bad Unicode character in ' + count + ' ');
 }
-
-function decimalToHexString(n) {
-  n = Number(n);
-  var h = "";
-  for (var i = 3; i >= 0; i--) {
-    if (n >= Math.pow(16, i)) {
-      var t = Math.floor(n / Math.pow(16, i));
-      n -= t * Math.pow(16, i);
-      if ( t >= 10 ) {
-        if ( t == 10 ) { h += "A"; }
-        if ( t == 11 ) { h += "B"; }
-        if ( t == 12 ) { h += "C"; }
-        if ( t == 13 ) { h += "D"; }
-        if ( t == 14 ) { h += "E"; }
-        if ( t == 15 ) { h += "F"; }
-      } else {
-        h += String(t);
-      }
-    } else {
-      h += "0";
-    }
-  }
-  return h;
-}
diff --git a/test/built-ins/decodeURI/S15.1.3.1_A1.8_T2.js b/test/built-ins/decodeURI/S15.1.3.1_A1.8_T2.js
index 95e93cfcc9..89303e011e 100644
--- a/test/built-ins/decodeURI/S15.1.3.1_A1.8_T2.js
+++ b/test/built-ins/decodeURI/S15.1.3.1_A1.8_T2.js
@@ -7,8 +7,8 @@ info: >
     string.charAt(k + 6) not equal "%", throw URIError
 es5id: 15.1.3.1_A1.8_T2
 description: >
-    Complex tests. B = [0xE0 - 0xEF],  string.charAt(k + 6) not equal
-    "%"
+    Complex tests. B = [0xE0 - 0xEF],  string.charAt(k + 6) not equal "%"
+includes: [decimalToHexString.js]
 ---*/
 
 var errorCount = 0;
@@ -18,9 +18,9 @@ var indexO = 0;
 
 for (var index = 0xE0; index <= 0xEF; index++) {
   count++; 
-  var hex = decimalToHexString(index);
+  var hex = decimalToPercentHexString(index);
   try {
-    decodeURI("%" + hex.substring(2) + "%A0111");
+    decodeURI(hex + "%A0111");
   } catch (e) { 
     if ((e instanceof URIError) === true) continue;                
   }
@@ -55,27 +55,3 @@ if (errorCount > 0) {
   }     
   $ERROR('Total error: ' + errorCount + ' bad Unicode character in ' + count + ' ');
 }
-
-function decimalToHexString(n) {
-  n = Number(n);
-  var h = "";
-  for (var i = 3; i >= 0; i--) {
-    if (n >= Math.pow(16, i)) {
-      var t = Math.floor(n / Math.pow(16, i));
-      n -= t * Math.pow(16, i);
-      if ( t >= 10 ) {
-        if ( t == 10 ) { h += "A"; }
-        if ( t == 11 ) { h += "B"; }
-        if ( t == 12 ) { h += "C"; }
-        if ( t == 13 ) { h += "D"; }
-        if ( t == 14 ) { h += "E"; }
-        if ( t == 15 ) { h += "F"; }
-      } else {
-        h += String(t);
-      }
-    } else {
-      h += "0";
-    }
-  }
-  return h;
-}
diff --git a/test/built-ins/decodeURI/S15.1.3.1_A1.9_T1.js b/test/built-ins/decodeURI/S15.1.3.1_A1.9_T1.js
index 31e5615798..2ec5d9b9db 100644
--- a/test/built-ins/decodeURI/S15.1.3.1_A1.9_T1.js
+++ b/test/built-ins/decodeURI/S15.1.3.1_A1.9_T1.js
@@ -7,8 +7,8 @@ info: >
     string.charAt(k + 6), string.charAt(k + 9) not equal "%", throw URIError
 es5id: 15.1.3.1_A1.9_T1
 description: >
-    Complex tests. B = [0xF0 - 0x0F7],  string.charAt(k + 3) not equal
-    "%"
+    Complex tests. B = [0xF0 - 0x0F7],  string.charAt(k + 3) not equal "%"
+includes: [decimalToHexString.js]
 ---*/
 
 var errorCount = 0;
@@ -18,9 +18,9 @@ var indexO = 0;
 
 for (var index = 0xF0; index <= 0xF7; index++) {
   count++; 
-  var hex = decimalToHexString(index);
+  var hex = decimalToPercentHexString(index);
   try {
-    decodeURI("%" + hex.substring(2) + "111%A0%A0");
+    decodeURI(hex + "111%A0%A0");
   } catch (e) { 
     if ((e instanceof URIError) === true) continue;                
   }
@@ -55,27 +55,3 @@ if (errorCount > 0) {
   }     
   $ERROR('Total error: ' + errorCount + ' bad Unicode character in ' + count + ' ');
 }
-
-function decimalToHexString(n) {
-  n = Number(n);
-  var h = "";
-  for (var i = 3; i >= 0; i--) {
-    if (n >= Math.pow(16, i)) {
-      var t = Math.floor(n / Math.pow(16, i));
-      n -= t * Math.pow(16, i);
-      if ( t >= 10 ) {
-        if ( t == 10 ) { h += "A"; }
-        if ( t == 11 ) { h += "B"; }
-        if ( t == 12 ) { h += "C"; }
-        if ( t == 13 ) { h += "D"; }
-        if ( t == 14 ) { h += "E"; }
-        if ( t == 15 ) { h += "F"; }
-      } else {
-        h += String(t);
-      }
-    } else {
-      h += "0";
-    }
-  }
-  return h;
-}
diff --git a/test/built-ins/decodeURI/S15.1.3.1_A1.9_T2.js b/test/built-ins/decodeURI/S15.1.3.1_A1.9_T2.js
index 2f19944845..7d1f1808c2 100644
--- a/test/built-ins/decodeURI/S15.1.3.1_A1.9_T2.js
+++ b/test/built-ins/decodeURI/S15.1.3.1_A1.9_T2.js
@@ -7,8 +7,8 @@ info: >
     string.charAt(k + 6), string.charAt(k + 9) not equal "%", throw URIError
 es5id: 15.1.3.1_A1.9_T2
 description: >
-    Complex tests. B = [0xF0 - 0x0F7],  string.charAt(k + 6) not equal
-    "%"
+    Complex tests. B = [0xF0 - 0x0F7],  string.charAt(k + 6) not equal "%"
+includes: [decimalToHexString.js]
 ---*/
 
 var errorCount = 0;
@@ -18,9 +18,9 @@ var indexO = 0;
 
 for (var index = 0xF0; index <= 0xF7; index++) {
   count++; 
-  var hex = decimalToHexString(index);
+  var hex = decimalToPercentHexString(index);
   try {
-    decodeURI("%" + hex.substring(2) + "%A0111%A0");
+    decodeURI(hex + "%A0111%A0");
   } catch (e) { 
     if ((e instanceof URIError) === true) continue;                
   }
@@ -55,27 +55,3 @@ if (errorCount > 0) {
   }     
   $ERROR('Total error: ' + errorCount + ' bad Unicode character in ' + count + ' ');
 }
-
-function decimalToHexString(n) {
-  n = Number(n);
-  var h = "";
-  for (var i = 3; i >= 0; i--) {
-    if (n >= Math.pow(16, i)) {
-      var t = Math.floor(n / Math.pow(16, i));
-      n -= t * Math.pow(16, i);
-      if ( t >= 10 ) {
-        if ( t == 10 ) { h += "A"; }
-        if ( t == 11 ) { h += "B"; }
-        if ( t == 12 ) { h += "C"; }
-        if ( t == 13 ) { h += "D"; }
-        if ( t == 14 ) { h += "E"; }
-        if ( t == 15 ) { h += "F"; }
-      } else {
-        h += String(t);
-      }
-    } else {
-      h += "0";
-    }
-  }
-  return h;
-}
diff --git a/test/built-ins/decodeURI/S15.1.3.1_A1.9_T3.js b/test/built-ins/decodeURI/S15.1.3.1_A1.9_T3.js
index 306d946d99..8289d50a9a 100644
--- a/test/built-ins/decodeURI/S15.1.3.1_A1.9_T3.js
+++ b/test/built-ins/decodeURI/S15.1.3.1_A1.9_T3.js
@@ -7,8 +7,8 @@ info: >
     string.charAt(k + 6), string.charAt(k + 9) not equal "%", throw URIError
 es5id: 15.1.3.1_A1.9_T3
 description: >
-    Complex tests. B = [0xF0 - 0x0F7],  string.charAt(k + 9) not equal
-    "%"
+    Complex tests. B = [0xF0 - 0x0F7],  string.charAt(k + 9) not equal "%"
+includes: [decimalToHexString.js]
 ---*/
 
 var errorCount = 0;
@@ -18,9 +18,9 @@ var indexO = 0;
 
 for (var index = 0xF0; index <= 0xF7; index++) {
   count++; 
-  var hex = decimalToHexString(index);
+  var hex = decimalToPercentHexString(index);
   try {
-    decodeURI("%" + hex.substring(2) + "%A0%A0111");
+    decodeURI(hex + "%A0%A0111");
   } catch (e) { 
     if ((e instanceof URIError) === true) continue;                
   }
@@ -55,27 +55,3 @@ if (errorCount > 0) {
   }     
   $ERROR('Total error: ' + errorCount + ' bad Unicode character in ' + count + ' ');
 }
-
-function decimalToHexString(n) {
-  n = Number(n);
-  var h = "";
-  for (var i = 3; i >= 0; i--) {
-    if (n >= Math.pow(16, i)) {
-      var t = Math.floor(n / Math.pow(16, i));
-      n -= t * Math.pow(16, i);
-      if ( t >= 10 ) {
-        if ( t == 10 ) { h += "A"; }
-        if ( t == 11 ) { h += "B"; }
-        if ( t == 12 ) { h += "C"; }
-        if ( t == 13 ) { h += "D"; }
-        if ( t == 14 ) { h += "E"; }
-        if ( t == 15 ) { h += "F"; }
-      } else {
-        h += String(t);
-      }
-    } else {
-      h += "0";
-    }
-  }
-  return h;
-}
diff --git a/test/built-ins/decodeURI/S15.1.3.1_A2.1_T1.js b/test/built-ins/decodeURI/S15.1.3.1_A2.1_T1.js
index 7f643eb763..15890e3459 100644
--- a/test/built-ins/decodeURI/S15.1.3.1_A2.1_T1.js
+++ b/test/built-ins/decodeURI/S15.1.3.1_A2.1_T1.js
@@ -5,6 +5,7 @@
 info: If string.charAt(k) not equal "%", return this char
 es5id: 15.1.3.1_A2.1_T1
 description: Complex tests
+includes: [decimalToHexString.js]
 ---*/
 
 //CHECK
@@ -30,27 +31,3 @@ for (var indexI = 0; indexI <= 65535; indexI++) {
 if (errorCount > 0) {    
   $ERROR('Total error: ' + errorCount + ' bad Unicode character in ' + count);
 }
-
-function decimalToHexString(n) {
-  n = Number(n);
-  var h = "";
-  for (var i = 3; i >= 0; i--) {
-    if (n >= Math.pow(16, i)) {
-      var t = Math.floor(n / Math.pow(16, i));
-      n -= t * Math.pow(16, i);
-      if ( t >= 10 ) {
-        if ( t == 10 ) { h += "A"; }
-        if ( t == 11 ) { h += "B"; }
-        if ( t == 12 ) { h += "C"; }
-        if ( t == 13 ) { h += "D"; }
-        if ( t == 14 ) { h += "E"; }
-        if ( t == 15 ) { h += "F"; }
-      } else {
-        h += String(t);
-      }
-    } else {
-      h += "0";
-    }
-  }
-  return h;
-}
diff --git a/test/built-ins/decodeURI/S15.1.3.1_A2.2_T1.js b/test/built-ins/decodeURI/S15.1.3.1_A2.2_T1.js
index ec98dc2e9a..143ea88f07 100644
--- a/test/built-ins/decodeURI/S15.1.3.1_A2.2_T1.js
+++ b/test/built-ins/decodeURI/S15.1.3.1_A2.2_T1.js
@@ -5,6 +5,7 @@
 info: If B1 = 0xxxxxxxx ([0x00 - 0x7F]), without [uriReserved, #], return B1
 es5id: 15.1.3.1_A2.2_T1
 description: Complex tests, use RFC 3629
+includes: [decimalToHexString.js]
 ---*/
 
 var errorCount = 0;
@@ -15,18 +16,15 @@ var uriReserved = [";", "/", "?", ":", "@", "&", "=", "+", "$", ","];
 l:
 for (var indexB1 = 0x00; indexB1 <= 0x7F; indexB1++) {       
   count++;
-  var hexB1 = decimalToHexString(indexB1);  
+  var hexB1 = decimalToPercentHexString(indexB1);
   var index = indexB1;  
-  try {
-    var hex = String.fromCharCode(index);
-    for (var indexC = 0; indexC < uriReserved.length; indexC++) {
-      if (hex === uriReserved[indexC]) continue l;        
-    } 
-    if (hex === "#") continue l;
-    if (decodeURI("%" + hexB1.substring(2)) === hex) continue;
-  } catch (e) {
-    if (e instanceof Test262Error) throw e;
-  }   
+  var hex = String.fromCharCode(index);
+  for (var indexC = 0; indexC < uriReserved.length; indexC++) {
+    if (hex === uriReserved[indexC]) continue l;
+  }
+  if (hex === "#") continue;
+  if (decodeURI(hexB1) === hex) continue;
+
   if (indexO === 0) { 
     indexO = index;
   } else {
@@ -58,27 +56,3 @@ if (errorCount > 0) {
   }     
   $ERROR('Total error: ' + errorCount + ' bad Unicode character in ' + count + ' ');
 }
-
-function decimalToHexString(n) {
-  n = Number(n);
-  var h = "";
-  for (var i = 3; i >= 0; i--) {
-    if (n >= Math.pow(16, i)) {
-      var t = Math.floor(n / Math.pow(16, i));
-      n -= t * Math.pow(16, i);
-      if ( t >= 10 ) {
-        if ( t == 10 ) { h += "A"; }
-        if ( t == 11 ) { h += "B"; }
-        if ( t == 12 ) { h += "C"; }
-        if ( t == 13 ) { h += "D"; }
-        if ( t == 14 ) { h += "E"; }
-        if ( t == 15 ) { h += "F"; }
-      } else {
-        h += String(t);
-      }
-    } else {
-      h += "0";
-    }
-  }
-  return h;
-}
diff --git a/test/built-ins/decodeURI/S15.1.3.1_A2.3_T1.js b/test/built-ins/decodeURI/S15.1.3.1_A2.3_T1.js
index 72458cf212..5a0786823d 100644
--- a/test/built-ins/decodeURI/S15.1.3.1_A2.3_T1.js
+++ b/test/built-ins/decodeURI/S15.1.3.1_A2.3_T1.js
@@ -7,6 +7,7 @@ info: >
     B1 = [0xC0, 0xC1], return UTF8(B1, B2)
 es5id: 15.1.3.1_A2.3_T1
 description: Complex tests, use RFC 3629
+includes: [decimalToHexString.js]
 ---*/
 
 var errorCount = 0;
@@ -15,16 +16,13 @@ var indexP;
 var indexO = 0;
 
 for (var indexB1 = 0xC2; indexB1 <= 0xDF; indexB1++) {     
-  var hexB1 = decimalToHexString(indexB1);
+  var hexB1 = decimalToPercentHexString(indexB1);
   for (var indexB2 = 0x80; indexB2 <= 0xBF; indexB2++) {
     count++;
-    var hexB2 = decimalToHexString(indexB2);
+    var hexB1_B2 = hexB1 + decimalToPercentHexString(indexB2);
     var index = (indexB1 & 0x1F) * 0x40 + (indexB2 & 0x3F);  
-    try {
-      if (decodeURI("%" + hexB1.substring(2) + "%" + hexB2.substring(2)) === String.fromCharCode(index)) continue;
-  } catch (e) {
-      if (e instanceof Test262Error) throw e;
-    }   
+    if (decodeURI(hexB1_B2) === String.fromCharCode(index)) continue;
+
     if (indexO === 0) { 
       indexO = index;
     } else {
@@ -57,27 +55,3 @@ if (errorCount > 0) {
   }     
   $ERROR('Total error: ' + errorCount + ' bad Unicode character in ' + count + ' ');
 }
-
-function decimalToHexString(n) {
-  n = Number(n);
-  var h = "";
-  for (var i = 3; i >= 0; i--) {
-    if (n >= Math.pow(16, i)) {
-      var t = Math.floor(n / Math.pow(16, i));
-      n -= t * Math.pow(16, i);
-      if ( t >= 10 ) {
-        if ( t == 10 ) { h += "A"; }
-        if ( t == 11 ) { h += "B"; }
-        if ( t == 12 ) { h += "C"; }
-        if ( t == 13 ) { h += "D"; }
-        if ( t == 14 ) { h += "E"; }
-        if ( t == 15 ) { h += "F"; }
-      } else {
-        h += String(t);
-      }
-    } else {
-      h += "0";
-    }
-  }
-  return h;
-}
diff --git a/test/built-ins/decodeURI/S15.1.3.1_A2.4_T1.js b/test/built-ins/decodeURI/S15.1.3.1_A2.4_T1.js
index 6558d09a94..edb3b78fca 100644
--- a/test/built-ins/decodeURI/S15.1.3.1_A2.4_T1.js
+++ b/test/built-ins/decodeURI/S15.1.3.1_A2.4_T1.js
@@ -8,6 +8,7 @@ info: >
     0xDFFF), return UTF8(B1, B2, B3)
 es5id: 15.1.3.1_A2.4_T1
 description: Complex tests, use RFC 3629
+includes: [decimalToHexString.js]
 ---*/
 
 var errorCount = 0;
@@ -16,20 +17,17 @@ var indexP;
 var indexO = 0;
 
 for (var indexB1 = 0xE0; indexB1 <= 0xEF; indexB1++) {     
-  var hexB1 = decimalToHexString(indexB1);
+  var hexB1 = decimalToPercentHexString(indexB1);
   for (var indexB2 = 0x80; indexB2 <= 0xBF; indexB2++) {
     if ((indexB1 === 0xE0) && (indexB2 <= 0x9F)) continue;
     if ((indexB1 === 0xED) && (0xA0 <= indexB2)) continue;         
-    var hexB2 = decimalToHexString(indexB2);
+    var hexB1_B2 = hexB1 + decimalToPercentHexString(indexB2);
     for (var indexB3 = 0x80; indexB3 <= 0xBF; indexB3++) {
       count++;
-      var hexB3 = decimalToHexString(indexB3);
+      var hexB1_B2_B3 = hexB1_B2 + decimalToPercentHexString(indexB3);
       var index = (indexB1 & 0x0F) * 0x1000 + (indexB2 & 0x3F) * 0x40 + (indexB3 & 0x3F);  
-      try {
-        if (decodeURI("%" + hexB1.substring(2) + "%" + hexB2.substring(2) + "%" + hexB3.substring(2)) === String.fromCharCode(index)) continue;
-      } catch (e) {
-        if (e instanceof Test262Error) throw e;
-      }   
+      if (decodeURI(hexB1_B2_B3) === String.fromCharCode(index)) continue;
+
       if (indexO === 0) { 
         indexO = index;
       } else {
@@ -63,27 +61,3 @@ if (errorCount > 0) {
   }     
   $ERROR('Total error: ' + errorCount + ' bad Unicode character in ' + count + ' ');
 }
-
-function decimalToHexString(n) {
-  n = Number(n);
-  var h = "";
-  for (var i = 3; i >= 0; i--) {
-    if (n >= Math.pow(16, i)) {
-      var t = Math.floor(n / Math.pow(16, i));
-      n -= t * Math.pow(16, i);
-      if ( t >= 10 ) {
-        if ( t == 10 ) { h += "A"; }
-        if ( t == 11 ) { h += "B"; }
-        if ( t == 12 ) { h += "C"; }
-        if ( t == 13 ) { h += "D"; }
-        if ( t == 14 ) { h += "E"; }
-        if ( t == 15 ) { h += "F"; }
-      } else {
-        h += String(t);
-      }
-    } else {
-      h += "0";
-    }
-  }
-  return h;
-}
diff --git a/test/built-ins/decodeURI/S15.1.3.1_A2.5_T1.js b/test/built-ins/decodeURI/S15.1.3.1_A2.5_T1.js
index b164850dc3..72e98b6e9a 100644
--- a/test/built-ins/decodeURI/S15.1.3.1_A2.5_T1.js
+++ b/test/built-ins/decodeURI/S15.1.3.1_A2.5_T1.js
@@ -8,6 +8,7 @@ info: >
     return UTF8(B1, B2, B3, B4)
 es5id: 15.1.3.1_A2.5_T1
 description: Complex tests, use RFC 3629
+includes: [decimalToHexString.js]
 ---*/
 
 var errorCount = 0;
@@ -16,24 +17,21 @@ var indexP;
 var indexO = 0;
 
 for (var indexB1 = 0xF0; indexB1 <= 0xF4; indexB1++) {     
-  var hexB1 = decimalToHexString(indexB1);
+  var hexB1 = decimalToPercentHexString(indexB1);
   for (var indexB2 = 0x80; indexB2 <= 0xBF; indexB2++) {
     if ((indexB1 === 0xF0) && (indexB2 <= 0x9F)) continue;            
     if ((indexB1 === 0xF4) && (indexB2 >= 0x90)) continue;
-    var hexB2 = decimalToHexString(indexB2);
+    var hexB1_B2 = hexB1 + decimalToPercentHexString(indexB2);
     for (var indexB3 = 0x80; indexB3 <= 0xBF; indexB3++) {
-      var hexB3 = decimalToHexString(indexB3);
+      var hexB1_B2_B3 = hexB1_B2 + decimalToPercentHexString(indexB3);
       for (var indexB4 = 0x80; indexB4 <= 0xBF; indexB4++) {
-        var hexB4 = decimalToHexString(indexB4);
+        var hexB1_B2_B3_B4 = hexB1_B2_B3 + decimalToPercentHexString(indexB4);
         count++;
         var index = (indexB1 & 0x07) * 0x40000 + (indexB2 & 0x3F) * 0x1000 + (indexB3 & 0x3F) * 0x40 + (indexB4 & 0x3F);
         var L = ((index - 0x10000) & 0x03FF) + 0xDC00;
         var H = (((index - 0x10000) >> 10) & 0x03FF) + 0xD800;  
-        try {
-          if (decodeURI("%" + hexB1.substring(3) + "%" + hexB2.substring(3) + "%" + hexB3.substring(3) + "%" + hexB4.substring(3)) === String.fromCharCode(H) + String.fromCharCode(L)) continue;
-        } catch (e) {
-          if (e instanceof Test262Error) throw e;
-        }   
+        if (decodeURI(hexB1_B2_B3_B4) === String.fromCharCode(H, L)) continue;
+
         if (indexO === 0) { 
           indexO = index;
         } else {
@@ -68,27 +66,3 @@ if (errorCount > 0) {
   }     
   $ERROR('Total error: ' + errorCount + ' bad Unicode character in ' + count + ' ');
 }
-
-function decimalToHexString(n) {
-  n = Number(n);
-  var h = "";
-  for (var i = 4; i >= 0; i--) {
-    if (n >= Math.pow(16, i)) {
-      var t = Math.floor(n / Math.pow(16, i));
-      n -= t * Math.pow(16, i);
-      if ( t >= 10 ) {
-        if ( t == 10 ) { h += "A"; }
-        if ( t == 11 ) { h += "B"; }
-        if ( t == 12 ) { h += "C"; }
-        if ( t == 13 ) { h += "D"; }
-        if ( t == 14 ) { h += "E"; }
-        if ( t == 15 ) { h += "F"; }
-      } else {
-        h += String(t);
-      }
-    } else {
-      h += "0";
-    }
-  }
-  return h;
-}
diff --git a/test/built-ins/decodeURIComponent/S15.1.3.2_A1.13_T1.js b/test/built-ins/decodeURIComponent/S15.1.3.2_A1.13_T1.js
index 4aa20cee26..978e7517a9 100644
--- a/test/built-ins/decodeURIComponent/S15.1.3.2_A1.13_T1.js
+++ b/test/built-ins/decodeURIComponent/S15.1.3.2_A1.13_T1.js
@@ -7,6 +7,7 @@ info: >
     throw URIError
 es5id: 15.1.3.2_A1.13_T1
 description: Complex tests. B = [0xC0 - 0xDF], C = [0x00, 0x7F]
+includes: [decimalToHexString.js]
 ---*/
 
 var errorCount = 0;
@@ -16,12 +17,12 @@ var indexO = 0;
 
 for (var indexB = 0xC0; indexB <= 0xDF; indexB++) {
   count++; 
-  var hexB = decimalToHexString(indexB);
+  var hexB = decimalToPercentHexString(indexB);
   var result = true;
   for (var indexC = 0x00; indexC <= 0x7F; indexC++) {
-    var hexC = decimalToHexString(indexC);
+    var hexC = decimalToPercentHexString(indexC);
     try {
-      decodeURIComponent("%" + hexB.substring(2) + "%" + hexC.substring(2));
+      decodeURIComponent(hexB + hexC);
     } catch (e) { 
       if ((e instanceof URIError) === true) continue;                
     }
@@ -60,27 +61,3 @@ if (errorCount > 0) {
   }     
   $ERROR('Total error: ' + errorCount + ' bad Unicode character in ' + count + ' ');
 }
-
-function decimalToHexString(n) {
-  n = Number(n);
-  var h = "";
-  for (var i = 3; i >= 0; i--) {
-    if (n >= Math.pow(16, i)) {
-      var t = Math.floor(n / Math.pow(16, i));
-      n -= t * Math.pow(16, i);
-      if ( t >= 10 ) {
-        if ( t == 10 ) { h += "A"; }
-        if ( t == 11 ) { h += "B"; }
-        if ( t == 12 ) { h += "C"; }
-        if ( t == 13 ) { h += "D"; }
-        if ( t == 14 ) { h += "E"; }
-        if ( t == 15 ) { h += "F"; }
-      } else {
-        h += String(t);
-      }
-    } else {
-      h += "0";
-    }
-  }
-  return h;
-}
diff --git a/test/built-ins/decodeURIComponent/S15.1.3.2_A1.13_T2.js b/test/built-ins/decodeURIComponent/S15.1.3.2_A1.13_T2.js
index bba768aac2..cac109a333 100644
--- a/test/built-ins/decodeURIComponent/S15.1.3.2_A1.13_T2.js
+++ b/test/built-ins/decodeURIComponent/S15.1.3.2_A1.13_T2.js
@@ -7,6 +7,7 @@ info: >
     throw URIError
 es5id: 15.1.3.2_A1.13_T2
 description: Complex tests. B = [0xC0 - 0xDF], C = [0xC0, 0xFF]
+includes: [decimalToHexString.js]
 ---*/
 
 var errorCount = 0;
@@ -16,12 +17,12 @@ var indexO = 0;
 
 for (var indexB = 0xC0; indexB <= 0xDF; indexB++) {
   count++; 
-  var hexB = decimalToHexString(indexB);
+  var hexB = decimalToPercentHexString(indexB);
   var result = true;
   for (var indexC = 0xC0; indexC <= 0xFF; indexC++) {
-    var hexC = decimalToHexString(indexC);
+    var hexC = decimalToPercentHexString(indexC);
     try {
-      decodeURIComponent("%" + hexB.substring(2) + "%" + hexC.substring(2));
+      decodeURIComponent(hexB + hexC);
     } catch (e) { 
       if ((e instanceof URIError) === true) continue;                
     }
@@ -60,27 +61,3 @@ if (errorCount > 0) {
   }     
   $ERROR('Total error: ' + errorCount + ' bad Unicode character in ' + count + ' ');
 }
-
-function decimalToHexString(n) {
-  n = Number(n);
-  var h = "";
-  for (var i = 3; i >= 0; i--) {
-    if (n >= Math.pow(16, i)) {
-      var t = Math.floor(n / Math.pow(16, i));
-      n -= t * Math.pow(16, i);
-      if ( t >= 10 ) {
-        if ( t == 10 ) { h += "A"; }
-        if ( t == 11 ) { h += "B"; }
-        if ( t == 12 ) { h += "C"; }
-        if ( t == 13 ) { h += "D"; }
-        if ( t == 14 ) { h += "E"; }
-        if ( t == 15 ) { h += "F"; }
-      } else {
-        h += String(t);
-      }
-    } else {
-      h += "0";
-    }
-  }
-  return h;
-}
diff --git a/test/built-ins/decodeURIComponent/S15.1.3.2_A1.14_T1.js b/test/built-ins/decodeURIComponent/S15.1.3.2_A1.14_T1.js
index 3f4ce70a37..1993a13420 100644
--- a/test/built-ins/decodeURIComponent/S15.1.3.2_A1.14_T1.js
+++ b/test/built-ins/decodeURIComponent/S15.1.3.2_A1.14_T1.js
@@ -7,6 +7,7 @@ info: >
     throw URIError
 es5id: 15.1.3.2_A1.14_T1
 description: Complex tests. B = [0xE0 - 0xEF], C = [0x00, 0x7F]
+includes: [decimalToHexString.js]
 ---*/
 
 var errorCount = 0;
@@ -16,12 +17,12 @@ var indexO = 0;
 
 for (var indexB = 0xE0; indexB <= 0xEF; indexB++) {
   count++; 
-  var hexB = decimalToHexString(indexB);
+  var hexB = decimalToPercentHexString(indexB);
   var result = true;
   for (var indexC = 0x00; indexC <= 0x7F; indexC++) {
-    var hexC = decimalToHexString(indexC);
+    var hexC = decimalToPercentHexString(indexC);
     try {
-      decodeURIComponent("%" + hexB.substring(2) + "%" + hexC.substring(2) + "%A0");
+      decodeURIComponent(hexB + hexC + "%A0");
     } catch (e) { 
       if ((e instanceof URIError) === true) continue;                
     }
@@ -60,27 +61,3 @@ if (errorCount > 0) {
   }     
   $ERROR('Total error: ' + errorCount + ' bad Unicode character in ' + count + ' ');
 }
-
-function decimalToHexString(n) {
-  n = Number(n);
-  var h = "";
-  for (var i = 3; i >= 0; i--) {
-    if (n >= Math.pow(16, i)) {
-      var t = Math.floor(n / Math.pow(16, i));
-      n -= t * Math.pow(16, i);
-      if ( t >= 10 ) {
-        if ( t == 10 ) { h += "A"; }
-        if ( t == 11 ) { h += "B"; }
-        if ( t == 12 ) { h += "C"; }
-        if ( t == 13 ) { h += "D"; }
-        if ( t == 14 ) { h += "E"; }
-        if ( t == 15 ) { h += "F"; }
-      } else {
-        h += String(t);
-      }
-    } else {
-      h += "0";
-    }
-  }
-  return h;
-}
diff --git a/test/built-ins/decodeURIComponent/S15.1.3.2_A1.14_T2.js b/test/built-ins/decodeURIComponent/S15.1.3.2_A1.14_T2.js
index b028c21a3e..5d5c9a7376 100644
--- a/test/built-ins/decodeURIComponent/S15.1.3.2_A1.14_T2.js
+++ b/test/built-ins/decodeURIComponent/S15.1.3.2_A1.14_T2.js
@@ -7,6 +7,7 @@ info: >
     throw URIError
 es5id: 15.1.3.2_A1.14_T2
 description: Complex tests. B = [0xE0 - 0xEF], C = [0x00, 0x7F]
+includes: [decimalToHexString.js]
 ---*/
 
 var errorCount = 0;
@@ -16,12 +17,12 @@ var indexO = 0;
 
 for (var indexB = 0xE0; indexB <= 0xEF; indexB++) {
   count++; 
-  var hexB = decimalToHexString(indexB);
+  var hexB = decimalToPercentHexString(indexB);
   var result = true;
   for (var indexC = 0x00; indexC <= 0x7F; indexC++) {
-    var hexC = decimalToHexString(indexC);
+    var hexC = decimalToPercentHexString(indexC);
     try {
-      decodeURIComponent("%" + hexB.substring(2) + "%A0" + "%" + hexC.substring(2));
+      decodeURIComponent(hexB + "%A0" + hexC);
     } catch (e) { 
       if ((e instanceof URIError) === true) continue;                
     }
@@ -60,27 +61,3 @@ if (errorCount > 0) {
   }     
   $ERROR('Total error: ' + errorCount + ' bad Unicode character in ' + count + ' ');
 }
-
-function decimalToHexString(n) {
-  n = Number(n);
-  var h = "";
-  for (var i = 3; i >= 0; i--) {
-    if (n >= Math.pow(16, i)) {
-      var t = Math.floor(n / Math.pow(16, i));
-      n -= t * Math.pow(16, i);
-      if ( t >= 10 ) {
-        if ( t == 10 ) { h += "A"; }
-        if ( t == 11 ) { h += "B"; }
-        if ( t == 12 ) { h += "C"; }
-        if ( t == 13 ) { h += "D"; }
-        if ( t == 14 ) { h += "E"; }
-        if ( t == 15 ) { h += "F"; }
-      } else {
-        h += String(t);
-      }
-    } else {
-      h += "0";
-    }
-  }
-  return h;
-}
diff --git a/test/built-ins/decodeURIComponent/S15.1.3.2_A1.14_T3.js b/test/built-ins/decodeURIComponent/S15.1.3.2_A1.14_T3.js
index 690481bdc6..6153a20932 100644
--- a/test/built-ins/decodeURIComponent/S15.1.3.2_A1.14_T3.js
+++ b/test/built-ins/decodeURIComponent/S15.1.3.2_A1.14_T3.js
@@ -7,6 +7,7 @@ info: >
     throw URIError
 es5id: 15.1.3.2_A1.14_T3
 description: Complex tests. B = [0xE0 - 0xEF], C = [0xC0, 0xFF]
+includes: [decimalToHexString.js]
 ---*/
 
 var errorCount = 0;
@@ -16,12 +17,12 @@ var indexO = 0;
 
 for (var indexB = 0xE0; indexB <= 0xEF; indexB++) {
   count++; 
-  var hexB = decimalToHexString(indexB);
+  var hexB = decimalToPercentHexString(indexB);
   var result = true;
   for (var indexC = 0xC0; indexC <= 0xFF; indexC++) {
-    var hexC = decimalToHexString(indexC);
+    var hexC = decimalToPercentHexString(indexC);
     try {
-      decodeURIComponent("%" + hexB.substring(2) + "%" + hexC.substring(2) + "%A0");
+      decodeURIComponent(hexB + hexC + "%A0");
     } catch (e) { 
       if ((e instanceof URIError) === true) continue;                
     }
@@ -60,27 +61,3 @@ if (errorCount > 0) {
   }     
   $ERROR('Total error: ' + errorCount + ' bad Unicode character in ' + count + ' ');
 }
-
-function decimalToHexString(n) {
-  n = Number(n);
-  var h = "";
-  for (var i = 3; i >= 0; i--) {
-    if (n >= Math.pow(16, i)) {
-      var t = Math.floor(n / Math.pow(16, i));
-      n -= t * Math.pow(16, i);
-      if ( t >= 10 ) {
-        if ( t == 10 ) { h += "A"; }
-        if ( t == 11 ) { h += "B"; }
-        if ( t == 12 ) { h += "C"; }
-        if ( t == 13 ) { h += "D"; }
-        if ( t == 14 ) { h += "E"; }
-        if ( t == 15 ) { h += "F"; }
-      } else {
-        h += String(t);
-      }
-    } else {
-      h += "0";
-    }
-  }
-  return h;
-}
diff --git a/test/built-ins/decodeURIComponent/S15.1.3.2_A1.14_T4.js b/test/built-ins/decodeURIComponent/S15.1.3.2_A1.14_T4.js
index 4c2d987473..04a8121d15 100644
--- a/test/built-ins/decodeURIComponent/S15.1.3.2_A1.14_T4.js
+++ b/test/built-ins/decodeURIComponent/S15.1.3.2_A1.14_T4.js
@@ -7,6 +7,7 @@ info: >
     throw URIError
 es5id: 15.1.3.2_A1.14_T4
 description: Complex tests. B = [0xE0 - 0xEF], C = [0xC0, 0xFF]
+includes: [decimalToHexString.js]
 ---*/
 
 var errorCount = 0;
@@ -16,12 +17,12 @@ var indexO = 0;
 
 for (var indexB = 0xE0; indexB <= 0xEF; indexB++) {
   count++; 
-  var hexB = decimalToHexString(indexB);
+  var hexB = decimalToPercentHexString(indexB);
   var result = true;
   for (var indexC = 0xC0; indexC <= 0xFF; indexC++) {
-    var hexC = decimalToHexString(indexC);
+    var hexC = decimalToPercentHexString(indexC);
     try {
-      decodeURIComponent("%" + hexB.substring(2) + "%A0" + "%" + hexC.substring(2));
+      decodeURIComponent(hexB + "%A0" + hexC);
     } catch (e) { 
       if ((e instanceof URIError) === true) continue;                
     }
@@ -60,27 +61,3 @@ if (errorCount > 0) {
   }     
   $ERROR('Total error: ' + errorCount + ' bad Unicode character in ' + count + ' ');
 }
-
-function decimalToHexString(n) {
-  n = Number(n);
-  var h = "";
-  for (var i = 3; i >= 0; i--) {
-    if (n >= Math.pow(16, i)) {
-      var t = Math.floor(n / Math.pow(16, i));
-      n -= t * Math.pow(16, i);
-      if ( t >= 10 ) {
-        if ( t == 10 ) { h += "A"; }
-        if ( t == 11 ) { h += "B"; }
-        if ( t == 12 ) { h += "C"; }
-        if ( t == 13 ) { h += "D"; }
-        if ( t == 14 ) { h += "E"; }
-        if ( t == 15 ) { h += "F"; }
-      } else {
-        h += String(t);
-      }
-    } else {
-      h += "0";
-    }
-  }
-  return h;
-}
diff --git a/test/built-ins/decodeURIComponent/S15.1.3.2_A1.15_T1.js b/test/built-ins/decodeURIComponent/S15.1.3.2_A1.15_T1.js
index 28861fab19..322785b1e2 100644
--- a/test/built-ins/decodeURIComponent/S15.1.3.2_A1.15_T1.js
+++ b/test/built-ins/decodeURIComponent/S15.1.3.2_A1.15_T1.js
@@ -7,6 +7,7 @@ info: >
     throw URIError
 es5id: 15.1.3.2_A1.15_T1
 description: Complex tests. B = [0xF0 - 0x0F7], C = [0x00, 0x7F]
+includes: [decimalToHexString.js]
 ---*/
 
 var errorCount = 0;
@@ -16,12 +17,12 @@ var indexO = 0;
 
 for (var indexB = 0xF0; indexB <= 0xF7; indexB++) {
   count++; 
-  var hexB = decimalToHexString(indexB);
+  var hexB = decimalToPercentHexString(indexB);
   var result = true;
   for (var indexC = 0x00; indexC <= 0x7F; indexC++) {
-    var hexC = decimalToHexString(indexC);
+    var hexC = decimalToPercentHexString(indexC);
     try {
-      decodeURIComponent("%" + hexB.substring(2) + "%" + hexC.substring(2) + "%A0%A0");
+      decodeURIComponent(hexB + hexC + "%A0%A0");
     } catch (e) { 
       if ((e instanceof URIError) === true) continue;                
     }
@@ -60,27 +61,3 @@ if (errorCount > 0) {
   }     
   $ERROR('Total error: ' + errorCount + ' bad Unicode character in ' + count + ' ');
 }
-
-function decimalToHexString(n) {
-  n = Number(n);
-  var h = "";
-  for (var i = 3; i >= 0; i--) {
-    if (n >= Math.pow(16, i)) {
-      var t = Math.floor(n / Math.pow(16, i));
-      n -= t * Math.pow(16, i);
-      if ( t >= 10 ) {
-        if ( t == 10 ) { h += "A"; }
-        if ( t == 11 ) { h += "B"; }
-        if ( t == 12 ) { h += "C"; }
-        if ( t == 13 ) { h += "D"; }
-        if ( t == 14 ) { h += "E"; }
-        if ( t == 15 ) { h += "F"; }
-      } else {
-        h += String(t);
-      }
-    } else {
-      h += "0";
-    }
-  }
-  return h;
-}
diff --git a/test/built-ins/decodeURIComponent/S15.1.3.2_A1.15_T2.js b/test/built-ins/decodeURIComponent/S15.1.3.2_A1.15_T2.js
index 6937c01f28..a6a40ba88e 100644
--- a/test/built-ins/decodeURIComponent/S15.1.3.2_A1.15_T2.js
+++ b/test/built-ins/decodeURIComponent/S15.1.3.2_A1.15_T2.js
@@ -7,6 +7,7 @@ info: >
     throw URIError
 es5id: 15.1.3.2_A1.15_T2
 description: Complex tests. B = [0xF0 - 0x0F7], C = [0x00, 0x7F]
+includes: [decimalToHexString.js]
 ---*/
 
 var errorCount = 0;
@@ -16,12 +17,12 @@ var indexO = 0;
 
 for (var indexB = 0xF0; indexB <= 0xF7; indexB++) {
   count++; 
-  var hexB = decimalToHexString(indexB);
+  var hexB = decimalToPercentHexString(indexB);
   var result = true;
   for (var indexC = 0x00; indexC <= 0x7F; indexC++) {
-    var hexC = decimalToHexString(indexC);
+    var hexC = decimalToPercentHexString(indexC);
     try {
-      decodeURIComponent("%" + hexB.substring(2) + "%A0" + "%" + hexC.substring(2) + "%A0");
+      decodeURIComponent(hexB + "%A0" + hexC + "%A0");
     } catch (e) { 
       if ((e instanceof URIError) === true) continue;                
     }
@@ -60,27 +61,3 @@ if (errorCount > 0) {
   }     
   $ERROR('Total error: ' + errorCount + ' bad Unicode character in ' + count + ' ');
 }
-
-function decimalToHexString(n) {
-  n = Number(n);
-  var h = "";
-  for (var i = 3; i >= 0; i--) {
-    if (n >= Math.pow(16, i)) {
-      var t = Math.floor(n / Math.pow(16, i));
-      n -= t * Math.pow(16, i);
-      if ( t >= 10 ) {
-        if ( t == 10 ) { h += "A"; }
-        if ( t == 11 ) { h += "B"; }
-        if ( t == 12 ) { h += "C"; }
-        if ( t == 13 ) { h += "D"; }
-        if ( t == 14 ) { h += "E"; }
-        if ( t == 15 ) { h += "F"; }
-      } else {
-        h += String(t);
-      }
-    } else {
-      h += "0";
-    }
-  }
-  return h;
-}
diff --git a/test/built-ins/decodeURIComponent/S15.1.3.2_A1.15_T3.js b/test/built-ins/decodeURIComponent/S15.1.3.2_A1.15_T3.js
index cb966fd6bd..f503082b2c 100644
--- a/test/built-ins/decodeURIComponent/S15.1.3.2_A1.15_T3.js
+++ b/test/built-ins/decodeURIComponent/S15.1.3.2_A1.15_T3.js
@@ -7,6 +7,7 @@ info: >
     throw URIError
 es5id: 15.1.3.2_A1.15_T3
 description: Complex tests. B = [0xF0 - 0x0F7], C = [0x00, 0x7F]
+includes: [decimalToHexString.js]
 ---*/
 
 var errorCount = 0;
@@ -16,12 +17,12 @@ var indexO = 0;
 
 for (var indexB = 0xF0; indexB <= 0xF7; indexB++) {
   count++; 
-  var hexB = decimalToHexString(indexB);
+  var hexB = decimalToPercentHexString(indexB);
   var result = true;
   for (var indexC = 0x00; indexC <= 0x7F; indexC++) {
-    var hexC = decimalToHexString(indexC);
+    var hexC = decimalToPercentHexString(indexC);
     try {
-      decodeURIComponent("%" + hexB.substring(2) + "%A0%A0" + "%" + hexC.substring(2));
+      decodeURIComponent(hexB + "%A0%A0" + hexC);
     } catch (e) { 
       if ((e instanceof URIError) === true) continue;                
     }
@@ -60,27 +61,3 @@ if (errorCount > 0) {
   }     
   $ERROR('Total error: ' + errorCount + ' bad Unicode character in ' + count + ' ');
 }
-
-function decimalToHexString(n) {
-  n = Number(n);
-  var h = "";
-  for (var i = 3; i >= 0; i--) {
-    if (n >= Math.pow(16, i)) {
-      var t = Math.floor(n / Math.pow(16, i));
-      n -= t * Math.pow(16, i);
-      if ( t >= 10 ) {
-        if ( t == 10 ) { h += "A"; }
-        if ( t == 11 ) { h += "B"; }
-        if ( t == 12 ) { h += "C"; }
-        if ( t == 13 ) { h += "D"; }
-        if ( t == 14 ) { h += "E"; }
-        if ( t == 15 ) { h += "F"; }
-      } else {
-        h += String(t);
-      }
-    } else {
-      h += "0";
-    }
-  }
-  return h;
-}
diff --git a/test/built-ins/decodeURIComponent/S15.1.3.2_A1.15_T4.js b/test/built-ins/decodeURIComponent/S15.1.3.2_A1.15_T4.js
index dff7c9a850..b752791481 100644
--- a/test/built-ins/decodeURIComponent/S15.1.3.2_A1.15_T4.js
+++ b/test/built-ins/decodeURIComponent/S15.1.3.2_A1.15_T4.js
@@ -7,6 +7,7 @@ info: >
     throw URIError
 es5id: 15.1.3.2_A1.15_T4
 description: Complex tests. B = [0xF0 - 0x0F7], C = [0xC0, 0xFF]
+includes: [decimalToHexString.js]
 ---*/
 
 var errorCount = 0;
@@ -16,12 +17,12 @@ var indexO = 0;
 
 for (var indexB = 0xF0; indexB <= 0xF7; indexB++) {
   count++; 
-  var hexB = decimalToHexString(indexB);
+  var hexB = decimalToPercentHexString(indexB);
   var result = true;
   for (var indexC = 0xC0; indexC <= 0xFF; indexC++) {
-    var hexC = decimalToHexString(indexC);
+    var hexC = decimalToPercentHexString(indexC);
     try {
-      decodeURIComponent("%" + hexB.substring(2) + "%" + hexC.substring(2) + "%A0%A0");
+      decodeURIComponent(hexB + hexC + "%A0%A0");
     } catch (e) { 
       if ((e instanceof URIError) === true) continue;                
     }
@@ -60,27 +61,3 @@ if (errorCount > 0) {
   }     
   $ERROR('Total error: ' + errorCount + ' bad Unicode character in ' + count + ' ');
 }
-
-function decimalToHexString(n) {
-  n = Number(n);
-  var h = "";
-  for (var i = 3; i >= 0; i--) {
-    if (n >= Math.pow(16, i)) {
-      var t = Math.floor(n / Math.pow(16, i));
-      n -= t * Math.pow(16, i);
-      if ( t >= 10 ) {
-        if ( t == 10 ) { h += "A"; }
-        if ( t == 11 ) { h += "B"; }
-        if ( t == 12 ) { h += "C"; }
-        if ( t == 13 ) { h += "D"; }
-        if ( t == 14 ) { h += "E"; }
-        if ( t == 15 ) { h += "F"; }
-      } else {
-        h += String(t);
-      }
-    } else {
-      h += "0";
-    }
-  }
-  return h;
-}
diff --git a/test/built-ins/decodeURIComponent/S15.1.3.2_A1.15_T5.js b/test/built-ins/decodeURIComponent/S15.1.3.2_A1.15_T5.js
index 0220be857d..072aabdd65 100644
--- a/test/built-ins/decodeURIComponent/S15.1.3.2_A1.15_T5.js
+++ b/test/built-ins/decodeURIComponent/S15.1.3.2_A1.15_T5.js
@@ -7,6 +7,7 @@ info: >
     throw URIError
 es5id: 15.1.3.2_A1.15_T5
 description: Complex tests. B = [0xF0 - 0x0F7], C = [0xC0, 0xFF]
+includes: [decimalToHexString.js]
 ---*/
 
 var errorCount = 0;
@@ -16,12 +17,12 @@ var indexO = 0;
 
 for (var indexB = 0xF0; indexB <= 0xF7; indexB++) {
   count++; 
-  var hexB = decimalToHexString(indexB);
+  var hexB = decimalToPercentHexString(indexB);
   var result = true;
   for (var indexC = 0xC0; indexC <= 0xFF; indexC++) {
-    var hexC = decimalToHexString(indexC);
+    var hexC = decimalToPercentHexString(indexC);
     try {
-      decodeURIComponent("%" + hexB.substring(2) + "%A0" + "%" + hexC.substring(2) + "%A0");
+      decodeURIComponent(hexB + "%A0" + hexC + "%A0");
     } catch (e) { 
       if ((e instanceof URIError) === true) continue;                
     }
@@ -60,27 +61,3 @@ if (errorCount > 0) {
   }     
   $ERROR('Total error: ' + errorCount + ' bad Unicode character in ' + count + ' ');
 }
-
-function decimalToHexString(n) {
-  n = Number(n);
-  var h = "";
-  for (var i = 3; i >= 0; i--) {
-    if (n >= Math.pow(16, i)) {
-      var t = Math.floor(n / Math.pow(16, i));
-      n -= t * Math.pow(16, i);
-      if ( t >= 10 ) {
-        if ( t == 10 ) { h += "A"; }
-        if ( t == 11 ) { h += "B"; }
-        if ( t == 12 ) { h += "C"; }
-        if ( t == 13 ) { h += "D"; }
-        if ( t == 14 ) { h += "E"; }
-        if ( t == 15 ) { h += "F"; }
-      } else {
-        h += String(t);
-      }
-    } else {
-      h += "0";
-    }
-  }
-  return h;
-}
diff --git a/test/built-ins/decodeURIComponent/S15.1.3.2_A1.15_T6.js b/test/built-ins/decodeURIComponent/S15.1.3.2_A1.15_T6.js
index 02941b07e6..777672e792 100644
--- a/test/built-ins/decodeURIComponent/S15.1.3.2_A1.15_T6.js
+++ b/test/built-ins/decodeURIComponent/S15.1.3.2_A1.15_T6.js
@@ -7,6 +7,7 @@ info: >
     throw URIError
 es5id: 15.1.3.2_A1.15_T6
 description: Complex tests. B = [0xF0 - 0x0F7], C = [0xC0, 0xFF]
+includes: [decimalToHexString.js]
 ---*/
 
 var errorCount = 0;
@@ -16,12 +17,12 @@ var indexO = 0;
 
 for (var indexB = 0xF0; indexB <= 0xF7; indexB++) {
   count++; 
-  var hexB = decimalToHexString(indexB);
+  var hexB = decimalToPercentHexString(indexB);
   var result = true;
   for (var indexC = 0xC0; indexC <= 0xFF; indexC++) {
-    var hexC = decimalToHexString(indexC);
+    var hexC = decimalToPercentHexString(indexC);
     try {
-      decodeURIComponent("%" + hexB.substring(2) + "%A0%A0" + "%" + hexC.substring(2));
+      decodeURIComponent(hexB + "%A0%A0" + hexC);
     } catch (e) { 
       if ((e instanceof URIError) === true) continue;                
     }
@@ -60,27 +61,3 @@ if (errorCount > 0) {
   }     
   $ERROR('Total error: ' + errorCount + ' bad Unicode character in ' + count + ' ');
 }
-
-function decimalToHexString(n) {
-  n = Number(n);
-  var h = "";
-  for (var i = 3; i >= 0; i--) {
-    if (n >= Math.pow(16, i)) {
-      var t = Math.floor(n / Math.pow(16, i));
-      n -= t * Math.pow(16, i);
-      if ( t >= 10 ) {
-        if ( t == 10 ) { h += "A"; }
-        if ( t == 11 ) { h += "B"; }
-        if ( t == 12 ) { h += "C"; }
-        if ( t == 13 ) { h += "D"; }
-        if ( t == 14 ) { h += "E"; }
-        if ( t == 15 ) { h += "F"; }
-      } else {
-        h += String(t);
-      }
-    } else {
-      h += "0";
-    }
-  }
-  return h;
-}
diff --git a/test/built-ins/decodeURIComponent/S15.1.3.2_A1.3_T1.js b/test/built-ins/decodeURIComponent/S15.1.3.2_A1.3_T1.js
index 98a0977a78..99073d74dd 100644
--- a/test/built-ins/decodeURIComponent/S15.1.3.2_A1.3_T1.js
+++ b/test/built-ins/decodeURIComponent/S15.1.3.2_A1.3_T1.js
@@ -5,6 +5,7 @@
 info: If B = 10xxxxxx or B = 11111xxx, throw URIError
 es5id: 15.1.3.2_A1.3_T1
 description: Complex tests. B = 10xxxxxx -> B in [0x80 - 0xBF]
+includes: [decimalToHexString.js]
 ---*/
 
 var errorCount = 0;
@@ -14,9 +15,9 @@ var indexO = 0;
 
 for (var index = 0x80; index <= 0xBF; index++) {
   count++; 
-  var hex = decimalToHexString(index);
+  var hex = decimalToPercentHexString(index);
   try {
-    decodeURIComponent("%" + hex.substring(2));
+    decodeURIComponent(hex);
   } catch (e) { 
     if ((e instanceof URIError) === true) continue;                
   }
@@ -51,27 +52,3 @@ if (errorCount > 0) {
   }     
   $ERROR('Total error: ' + errorCount + ' bad Unicode character in ' + count + ' ');
 }
-
-function decimalToHexString(n) {
-  n = Number(n);
-  var h = "";
-  for (var i = 3; i >= 0; i--) {
-    if (n >= Math.pow(16, i)) {
-      var t = Math.floor(n / Math.pow(16, i));
-      n -= t * Math.pow(16, i);
-      if ( t >= 10 ) {
-        if ( t == 10 ) { h += "A"; }
-        if ( t == 11 ) { h += "B"; }
-        if ( t == 12 ) { h += "C"; }
-        if ( t == 13 ) { h += "D"; }
-        if ( t == 14 ) { h += "E"; }
-        if ( t == 15 ) { h += "F"; }
-      } else {
-        h += String(t);
-      }
-    } else {
-      h += "0";
-    }
-  }
-  return h;
-}
diff --git a/test/built-ins/decodeURIComponent/S15.1.3.2_A1.3_T2.js b/test/built-ins/decodeURIComponent/S15.1.3.2_A1.3_T2.js
index 9d0bfc1667..d4cdfc6ff6 100644
--- a/test/built-ins/decodeURIComponent/S15.1.3.2_A1.3_T2.js
+++ b/test/built-ins/decodeURIComponent/S15.1.3.2_A1.3_T2.js
@@ -5,6 +5,7 @@
 info: If B = 10xxxxxx or B = 11111xxx, throw URIError
 es5id: 15.1.3.2_A1.3_T2
 description: Complex tests. B = 11111xxx -> B in [0xF8 - 0xFF]
+includes: [decimalToHexString.js]
 ---*/
 
 var errorCount = 0;
@@ -14,9 +15,9 @@ var indexO = 0;
 
 for (var index = 0xF8; index <= 0xFF; index++) {
   count++; 
-  var hex = decimalToHexString(index);
+  var hex = decimalToPercentHexString(index);
   try {
-    decodeURIComponent("%" + hex.substring(2));
+    decodeURIComponent(hex);
   } catch (e) { 
     if ((e instanceof URIError) === true) continue;                
   }
@@ -51,27 +52,3 @@ if (errorCount > 0) {
   }     
   $ERROR('Total error: ' + errorCount + ' bad Unicode character in ' + count + ' ');
 }
-
-function decimalToHexString(n) {
-  n = Number(n);
-  var h = "";
-  for (var i = 3; i >= 0; i--) {
-    if (n >= Math.pow(16, i)) {
-      var t = Math.floor(n / Math.pow(16, i));
-      n -= t * Math.pow(16, i);
-      if ( t >= 10 ) {
-        if ( t == 10 ) { h += "A"; }
-        if ( t == 11 ) { h += "B"; }
-        if ( t == 12 ) { h += "C"; }
-        if ( t == 13 ) { h += "D"; }
-        if ( t == 14 ) { h += "E"; }
-        if ( t == 15 ) { h += "F"; }
-      } else {
-        h += String(t);
-      }
-    } else {
-      h += "0";
-    }
-  }
-  return h;
-}
diff --git a/test/built-ins/decodeURIComponent/S15.1.3.2_A1.4_T1.js b/test/built-ins/decodeURIComponent/S15.1.3.2_A1.4_T1.js
index 7e88a8d05f..97108d76a6 100644
--- a/test/built-ins/decodeURIComponent/S15.1.3.2_A1.4_T1.js
+++ b/test/built-ins/decodeURIComponent/S15.1.3.2_A1.4_T1.js
@@ -5,6 +5,7 @@
 info: If B = 110xxxxx (n = 2) and (k + 2) + 3 >= length, throw URIError
 es5id: 15.1.3.2_A1.4_T1
 description: Complex tests. B = [0xC0 - 0xDF]
+includes: [decimalToHexString.js]
 ---*/
 
 var errorCount = 0;
@@ -17,9 +18,9 @@ for (var index = 0xC0; index <= 0xDF; index++) {
   var str = "";
   var result = true;
   for (var len = 0; len < 3; len++) {
-    var hex = decimalToHexString(index);
+    var hex = decimalToPercentHexString(index);
     try {
-      decodeURIComponent("%" + hex.substring(2) + str);      
+      decodeURIComponent(hex + str);
     } catch (e) { 
       if ((e instanceof URIError) === true) continue;                
     }
@@ -59,27 +60,3 @@ if (errorCount > 0) {
   }     
   $ERROR('Total error: ' + errorCount + ' bad Unicode character in ' + count + ' ');
 }
-
-function decimalToHexString(n) {
-  n = Number(n);
-  var h = "";
-  for (var i = 3; i >= 0; i--) {
-    if (n >= Math.pow(16, i)) {
-      var t = Math.floor(n / Math.pow(16, i));
-      n -= t * Math.pow(16, i);
-      if ( t >= 10 ) {
-        if ( t == 10 ) { h += "A"; }
-        if ( t == 11 ) { h += "B"; }
-        if ( t == 12 ) { h += "C"; }
-        if ( t == 13 ) { h += "D"; }
-        if ( t == 14 ) { h += "E"; }
-        if ( t == 15 ) { h += "F"; }
-      } else {
-        h += String(t);
-      }
-    } else {
-      h += "0";
-    }
-  }
-  return h;
-}
diff --git a/test/built-ins/decodeURIComponent/S15.1.3.2_A1.5_T1.js b/test/built-ins/decodeURIComponent/S15.1.3.2_A1.5_T1.js
index ef72254a57..782bb26d40 100644
--- a/test/built-ins/decodeURIComponent/S15.1.3.2_A1.5_T1.js
+++ b/test/built-ins/decodeURIComponent/S15.1.3.2_A1.5_T1.js
@@ -5,6 +5,7 @@
 info: If B = 1110xxxx (n = 3) and (k + 2) + 6 >= length, throw URIError
 es5id: 15.1.3.2_A1.5_T1
 description: Complex tests. B = [0xE0 - 0xEF]
+includes: [decimalToHexString.js]
 ---*/
 
 var errorCount = 0;
@@ -17,9 +18,9 @@ for (var index = 0xE0; index <= 0xEF; index++) {
   var str = "";
   var result = true;
   for (var len = 0; len < 6; len++) {
-    var hex = decimalToHexString(index);
+    var hex = decimalToPercentHexString(index);
     try {
-      decodeURIComponent("%" + hex.substring(2) + str);      
+      decodeURIComponent(hex + str);
     } catch (e) { 
       if ((e instanceof URIError) === true) continue;                
     }
@@ -59,27 +60,3 @@ if (errorCount > 0) {
   }     
   $ERROR('Total error: ' + errorCount + ' bad Unicode character in ' + count + ' ');
 }
-
-function decimalToHexString(n) {
-  n = Number(n);
-  var h = "";
-  for (var i = 3; i >= 0; i--) {
-    if (n >= Math.pow(16, i)) {
-      var t = Math.floor(n / Math.pow(16, i));
-      n -= t * Math.pow(16, i);
-      if ( t >= 10 ) {
-        if ( t == 10 ) { h += "A"; }
-        if ( t == 11 ) { h += "B"; }
-        if ( t == 12 ) { h += "C"; }
-        if ( t == 13 ) { h += "D"; }
-        if ( t == 14 ) { h += "E"; }
-        if ( t == 15 ) { h += "F"; }
-      } else {
-        h += String(t);
-      }
-    } else {
-      h += "0";
-    }
-  }
-  return h;
-}
diff --git a/test/built-ins/decodeURIComponent/S15.1.3.2_A1.6_T1.js b/test/built-ins/decodeURIComponent/S15.1.3.2_A1.6_T1.js
index 3c68d04c68..8e5e0f6764 100644
--- a/test/built-ins/decodeURIComponent/S15.1.3.2_A1.6_T1.js
+++ b/test/built-ins/decodeURIComponent/S15.1.3.2_A1.6_T1.js
@@ -5,6 +5,7 @@
 info: If B = 11110xxx (n = 4) and (k + 2) + 9 >= length, throw URIError
 es5id: 15.1.3.2_A1.6_T1
 description: Complex tests. B = [0xF0 - 0xF7]
+includes: [decimalToHexString.js]
 ---*/
 
 var errorCount = 0;
@@ -17,9 +18,9 @@ for (var index = 0xF0; index <= 0xF7; index++) {
   var str = "";
   var result = true;
   for (var len = 0; len < 9; len++) {
-    var hex = decimalToHexString(index);
+    var hex = decimalToPercentHexString(index);
     try {
-      decodeURIComponent("%" + hex.substring(2) + str);      
+      decodeURIComponent(hex + str);
     } catch (e) { 
       if ((e instanceof URIError) === true) continue;                
     }
@@ -59,27 +60,3 @@ if (errorCount > 0) {
   }     
   $ERROR('Total error: ' + errorCount + ' bad Unicode character in ' + count + ' ');
 }
-
-function decimalToHexString(n) {
-  n = Number(n);
-  var h = "";
-  for (var i = 3; i >= 0; i--) {
-    if (n >= Math.pow(16, i)) {
-      var t = Math.floor(n / Math.pow(16, i));
-      n -= t * Math.pow(16, i);
-      if ( t >= 10 ) {
-        if ( t == 10 ) { h += "A"; }
-        if ( t == 11 ) { h += "B"; }
-        if ( t == 12 ) { h += "C"; }
-        if ( t == 13 ) { h += "D"; }
-        if ( t == 14 ) { h += "E"; }
-        if ( t == 15 ) { h += "F"; }
-      } else {
-        h += String(t);
-      }
-    } else {
-      h += "0";
-    }
-  }
-  return h;
-}
diff --git a/test/built-ins/decodeURIComponent/S15.1.3.2_A1.7_T1.js b/test/built-ins/decodeURIComponent/S15.1.3.2_A1.7_T1.js
index 092e4602de..488c589d3f 100644
--- a/test/built-ins/decodeURIComponent/S15.1.3.2_A1.7_T1.js
+++ b/test/built-ins/decodeURIComponent/S15.1.3.2_A1.7_T1.js
@@ -7,6 +7,7 @@ info: >
     URIError
 es5id: 15.1.3.2_A1.7_T1
 description: Complex tests. B = [0xC0 - 0xDF]
+includes: [decimalToHexString.js]
 ---*/
 
 var errorCount = 0;
@@ -16,9 +17,9 @@ var indexO = 0;
 
 for (var index = 0xC0; index <= 0xDF; index++) {
   count++; 
-  var hex = decimalToHexString(index);
+  var hex = decimalToPercentHexString(index);
   try {
-    decodeURIComponent("%" + hex.substring(2) + "111");
+    decodeURIComponent(hex + "111");
   } catch (e) { 
     if ((e instanceof URIError) === true) continue;                
   }
@@ -53,27 +54,3 @@ if (errorCount > 0) {
   }     
   $ERROR('Total error: ' + errorCount + ' bad Unicode character in ' + count + ' ');
 }
-
-function decimalToHexString(n) {
-  n = Number(n);
-  var h = "";
-  for (var i = 3; i >= 0; i--) {
-    if (n >= Math.pow(16, i)) {
-      var t = Math.floor(n / Math.pow(16, i));
-      n -= t * Math.pow(16, i);
-      if ( t >= 10 ) {
-        if ( t == 10 ) { h += "A"; }
-        if ( t == 11 ) { h += "B"; }
-        if ( t == 12 ) { h += "C"; }
-        if ( t == 13 ) { h += "D"; }
-        if ( t == 14 ) { h += "E"; }
-        if ( t == 15 ) { h += "F"; }
-      } else {
-        h += String(t);
-      }
-    } else {
-      h += "0";
-    }
-  }
-  return h;
-}
diff --git a/test/built-ins/decodeURIComponent/S15.1.3.2_A1.8_T1.js b/test/built-ins/decodeURIComponent/S15.1.3.2_A1.8_T1.js
index 6871ba649a..672cc54437 100644
--- a/test/built-ins/decodeURIComponent/S15.1.3.2_A1.8_T1.js
+++ b/test/built-ins/decodeURIComponent/S15.1.3.2_A1.8_T1.js
@@ -7,8 +7,8 @@ info: >
     string.charAt(k + 6) not equal "%", throw URIError
 es5id: 15.1.3.2_A1.8_T1
 description: >
-    Complex tests. B = [0xE0 - 0xEF],  string.charAt(k + 3) not equal
-    "%"
+    Complex tests. B = [0xE0 - 0xEF],  string.charAt(k + 3) not equal "%"
+includes: [decimalToHexString.js]
 ---*/
 
 var errorCount = 0;
@@ -18,9 +18,9 @@ var indexO = 0;
 
 for (var index = 0xE0; index <= 0xEF; index++) {
   count++; 
-  var hex = decimalToHexString(index);
+  var hex = decimalToPercentHexString(index);
   try {
-    decodeURIComponent("%" + hex.substring(2) + "111%A0");
+    decodeURIComponent(hex + "111%A0");
   } catch (e) { 
     if ((e instanceof URIError) === true) continue;                
   }
@@ -55,27 +55,3 @@ if (errorCount > 0) {
   }     
   $ERROR('Total error: ' + errorCount + ' bad Unicode character in ' + count + ' ');
 }
-
-function decimalToHexString(n) {
-  n = Number(n);
-  var h = "";
-  for (var i = 3; i >= 0; i--) {
-    if (n >= Math.pow(16, i)) {
-      var t = Math.floor(n / Math.pow(16, i));
-      n -= t * Math.pow(16, i);
-      if ( t >= 10 ) {
-        if ( t == 10 ) { h += "A"; }
-        if ( t == 11 ) { h += "B"; }
-        if ( t == 12 ) { h += "C"; }
-        if ( t == 13 ) { h += "D"; }
-        if ( t == 14 ) { h += "E"; }
-        if ( t == 15 ) { h += "F"; }
-      } else {
-        h += String(t);
-      }
-    } else {
-      h += "0";
-    }
-  }
-  return h;
-}
diff --git a/test/built-ins/decodeURIComponent/S15.1.3.2_A1.8_T2.js b/test/built-ins/decodeURIComponent/S15.1.3.2_A1.8_T2.js
index 5a5c1df077..d562ac053e 100644
--- a/test/built-ins/decodeURIComponent/S15.1.3.2_A1.8_T2.js
+++ b/test/built-ins/decodeURIComponent/S15.1.3.2_A1.8_T2.js
@@ -7,8 +7,8 @@ info: >
     string.charAt(k + 6) not equal "%", throw URIError
 es5id: 15.1.3.2_A1.8_T2
 description: >
-    Complex tests. B = [0xE0 - 0xEF],  string.charAt(k + 6) not equal
-    "%"
+    Complex tests. B = [0xE0 - 0xEF],  string.charAt(k + 6) not equal "%"
+includes: [decimalToHexString.js]
 ---*/
 
 var errorCount = 0;
@@ -18,9 +18,9 @@ var indexO = 0;
 
 for (var index = 0xE0; index <= 0xEF; index++) {
   count++; 
-  var hex = decimalToHexString(index);
+  var hex = decimalToPercentHexString(index);
   try {
-    decodeURIComponent("%" + hex.substring(2) + "%A0111");
+    decodeURIComponent(hex + "%A0111");
   } catch (e) { 
     if ((e instanceof URIError) === true) continue;                
   }
@@ -55,27 +55,3 @@ if (errorCount > 0) {
   }     
   $ERROR('Total error: ' + errorCount + ' bad Unicode character in ' + count + ' ');
 }
-
-function decimalToHexString(n) {
-  n = Number(n);
-  var h = "";
-  for (var i = 3; i >= 0; i--) {
-    if (n >= Math.pow(16, i)) {
-      var t = Math.floor(n / Math.pow(16, i));
-      n -= t * Math.pow(16, i);
-      if ( t >= 10 ) {
-        if ( t == 10 ) { h += "A"; }
-        if ( t == 11 ) { h += "B"; }
-        if ( t == 12 ) { h += "C"; }
-        if ( t == 13 ) { h += "D"; }
-        if ( t == 14 ) { h += "E"; }
-        if ( t == 15 ) { h += "F"; }
-      } else {
-        h += String(t);
-      }
-    } else {
-      h += "0";
-    }
-  }
-  return h;
-}
diff --git a/test/built-ins/decodeURIComponent/S15.1.3.2_A1.9_T1.js b/test/built-ins/decodeURIComponent/S15.1.3.2_A1.9_T1.js
index 8b3ebb23fe..f2b31216a2 100644
--- a/test/built-ins/decodeURIComponent/S15.1.3.2_A1.9_T1.js
+++ b/test/built-ins/decodeURIComponent/S15.1.3.2_A1.9_T1.js
@@ -7,8 +7,8 @@ info: >
     string.charAt(k + 6), string.charAt(k + 9) not equal "%", throw URIError
 es5id: 15.1.3.2_A1.9_T1
 description: >
-    Complex tests. B = [0xF0 - 0x0F7],  string.charAt(k + 3) not equal
-    "%"
+    Complex tests. B = [0xF0 - 0x0F7],  string.charAt(k + 3) not equal "%"
+includes: [decimalToHexString.js]
 ---*/
 
 var errorCount = 0;
@@ -18,9 +18,9 @@ var indexO = 0;
 
 for (var index = 0xF0; index <= 0xF7; index++) {
   count++; 
-  var hex = decimalToHexString(index);
+  var hex = decimalToPercentHexString(index);
   try {
-    decodeURIComponent("%" + hex.substring(2) + "111%A0%A0");
+    decodeURIComponent(hex + "111%A0%A0");
   } catch (e) { 
     if ((e instanceof URIError) === true) continue;                
   }
@@ -55,27 +55,3 @@ if (errorCount > 0) {
   }     
   $ERROR('Total error: ' + errorCount + ' bad Unicode character in ' + count + ' ');
 }
-
-function decimalToHexString(n) {
-  n = Number(n);
-  var h = "";
-  for (var i = 3; i >= 0; i--) {
-    if (n >= Math.pow(16, i)) {
-      var t = Math.floor(n / Math.pow(16, i));
-      n -= t * Math.pow(16, i);
-      if ( t >= 10 ) {
-        if ( t == 10 ) { h += "A"; }
-        if ( t == 11 ) { h += "B"; }
-        if ( t == 12 ) { h += "C"; }
-        if ( t == 13 ) { h += "D"; }
-        if ( t == 14 ) { h += "E"; }
-        if ( t == 15 ) { h += "F"; }
-      } else {
-        h += String(t);
-      }
-    } else {
-      h += "0";
-    }
-  }
-  return h;
-}
diff --git a/test/built-ins/decodeURIComponent/S15.1.3.2_A1.9_T2.js b/test/built-ins/decodeURIComponent/S15.1.3.2_A1.9_T2.js
index 664cc07d32..1033aa1ae2 100644
--- a/test/built-ins/decodeURIComponent/S15.1.3.2_A1.9_T2.js
+++ b/test/built-ins/decodeURIComponent/S15.1.3.2_A1.9_T2.js
@@ -7,8 +7,8 @@ info: >
     string.charAt(k + 6), string.charAt(k + 9) not equal "%", throw URIError
 es5id: 15.1.3.2_A1.9_T2
 description: >
-    Complex tests. B = [0xF0 - 0x0F7],  string.charAt(k + 6) not equal
-    "%"
+    Complex tests. B = [0xF0 - 0x0F7],  string.charAt(k + 6) not equal "%"
+includes: [decimalToHexString.js]
 ---*/
 
 var errorCount = 0;
@@ -18,9 +18,9 @@ var indexO = 0;
 
 for (var index = 0xF0; index <= 0xF7; index++) {
   count++; 
-  var hex = decimalToHexString(index);
+  var hex = decimalToPercentHexString(index);
   try {
-    decodeURIComponent("%" + hex.substring(2) + "%A0111%A0");
+    decodeURIComponent(hex + "%A0111%A0");
   } catch (e) { 
     if ((e instanceof URIError) === true) continue;                
   }
@@ -55,27 +55,3 @@ if (errorCount > 0) {
   }     
   $ERROR('Total error: ' + errorCount + ' bad Unicode character in ' + count + ' ');
 }
-
-function decimalToHexString(n) {
-  n = Number(n);
-  var h = "";
-  for (var i = 3; i >= 0; i--) {
-    if (n >= Math.pow(16, i)) {
-      var t = Math.floor(n / Math.pow(16, i));
-      n -= t * Math.pow(16, i);
-      if ( t >= 10 ) {
-        if ( t == 10 ) { h += "A"; }
-        if ( t == 11 ) { h += "B"; }
-        if ( t == 12 ) { h += "C"; }
-        if ( t == 13 ) { h += "D"; }
-        if ( t == 14 ) { h += "E"; }
-        if ( t == 15 ) { h += "F"; }
-      } else {
-        h += String(t);
-      }
-    } else {
-      h += "0";
-    }
-  }
-  return h;
-}
diff --git a/test/built-ins/decodeURIComponent/S15.1.3.2_A1.9_T3.js b/test/built-ins/decodeURIComponent/S15.1.3.2_A1.9_T3.js
index 5f5813ace8..22f48126d8 100644
--- a/test/built-ins/decodeURIComponent/S15.1.3.2_A1.9_T3.js
+++ b/test/built-ins/decodeURIComponent/S15.1.3.2_A1.9_T3.js
@@ -7,8 +7,8 @@ info: >
     string.charAt(k + 6), string.charAt(k + 9) not equal "%", throw URIError
 es5id: 15.1.3.2_A1.9_T3
 description: >
-    Complex tests. B = [0xF0 - 0x0F7],  string.charAt(k + 9) not equal
-    "%"
+    Complex tests. B = [0xF0 - 0x0F7],  string.charAt(k + 9) not equal "%"
+includes: [decimalToHexString.js]
 ---*/
 
 var errorCount = 0;
@@ -18,9 +18,9 @@ var indexO = 0;
 
 for (var index = 0xF0; index <= 0xF7; index++) {
   count++; 
-  var hex = decimalToHexString(index);
+  var hex = decimalToPercentHexString(index);
   try {
-    decodeURIComponent("%" + hex.substring(2) + "%A0%A0111");
+    decodeURIComponent(hex + "%A0%A0111");
   } catch (e) { 
     if ((e instanceof URIError) === true) continue;                
   }
@@ -55,27 +55,3 @@ if (errorCount > 0) {
   }     
   $ERROR('Total error: ' + errorCount + ' bad Unicode character in ' + count + ' ');
 }
-
-function decimalToHexString(n) {
-  n = Number(n);
-  var h = "";
-  for (var i = 3; i >= 0; i--) {
-    if (n >= Math.pow(16, i)) {
-      var t = Math.floor(n / Math.pow(16, i));
-      n -= t * Math.pow(16, i);
-      if ( t >= 10 ) {
-        if ( t == 10 ) { h += "A"; }
-        if ( t == 11 ) { h += "B"; }
-        if ( t == 12 ) { h += "C"; }
-        if ( t == 13 ) { h += "D"; }
-        if ( t == 14 ) { h += "E"; }
-        if ( t == 15 ) { h += "F"; }
-      } else {
-        h += String(t);
-      }
-    } else {
-      h += "0";
-    }
-  }
-  return h;
-}
diff --git a/test/built-ins/decodeURIComponent/S15.1.3.2_A2.1_T1.js b/test/built-ins/decodeURIComponent/S15.1.3.2_A2.1_T1.js
index 6e5b14179e..05c7db39f7 100644
--- a/test/built-ins/decodeURIComponent/S15.1.3.2_A2.1_T1.js
+++ b/test/built-ins/decodeURIComponent/S15.1.3.2_A2.1_T1.js
@@ -5,6 +5,7 @@
 info: If string.charAt(k) not equal "%", return this char
 es5id: 15.1.3.2_A2.1_T1
 description: Complex tests
+includes: [decimalToHexString.js]
 ---*/
 
 //CHECK
@@ -30,27 +31,3 @@ for (var indexI = 0; indexI <= 65535; indexI++) {
 if (errorCount > 0) {    
   $ERROR('Total error: ' + errorCount + ' bad Unicode character in ' + count);
 }
-
-function decimalToHexString(n) {
-  n = Number(n);
-  var h = "";
-  for (var i = 3; i >= 0; i--) {
-    if (n >= Math.pow(16, i)) {
-      var t = Math.floor(n / Math.pow(16, i));
-      n -= t * Math.pow(16, i);
-      if ( t >= 10 ) {
-        if ( t == 10 ) { h += "A"; }
-        if ( t == 11 ) { h += "B"; }
-        if ( t == 12 ) { h += "C"; }
-        if ( t == 13 ) { h += "D"; }
-        if ( t == 14 ) { h += "E"; }
-        if ( t == 15 ) { h += "F"; }
-      } else {
-        h += String(t);
-      }
-    } else {
-      h += "0";
-    }
-  }
-  return h;
-}
diff --git a/test/built-ins/decodeURIComponent/S15.1.3.2_A2.2_T1.js b/test/built-ins/decodeURIComponent/S15.1.3.2_A2.2_T1.js
index 6d6811929e..59074ba2dd 100644
--- a/test/built-ins/decodeURIComponent/S15.1.3.2_A2.2_T1.js
+++ b/test/built-ins/decodeURIComponent/S15.1.3.2_A2.2_T1.js
@@ -5,6 +5,7 @@
 info: If B1 = 0xxxxxxxx ([0x00 - 0x7F]), return B1
 es5id: 15.1.3.2_A2.2_T1
 description: Complex tests, use RFC 3629
+includes: [decimalToHexString.js]
 ---*/
 
 var errorCount = 0;
@@ -13,14 +14,11 @@ var indexP;
 var indexO = 0;
 for (var indexB1 = 0x00; indexB1 <= 0x7F; indexB1++) {
   count++;
-  var hexB1 = decimalToHexString(indexB1);  
+  var hexB1 = decimalToPercentHexString(indexB1);
   var index = indexB1;  
-  try {
-    var hex = String.fromCharCode(index);
-    if (decodeURIComponent("%" + hexB1.substring(2)) === hex) continue;
-  } catch (e) {
-    if (e instanceof Test262Error) throw e;
-  }   
+  var hex = String.fromCharCode(index);
+  if (decodeURIComponent(hexB1) === hex) continue;
+
   if (indexO === 0) { 
     indexO = index;
   } else {
@@ -52,27 +50,3 @@ if (errorCount > 0) {
   }     
   $ERROR('Total error: ' + errorCount + ' bad Unicode character in ' + count + ' ');
 }
-
-function decimalToHexString(n) {
-  n = Number(n);
-  var h = "";
-  for (var i = 3; i >= 0; i--) {
-    if (n >= Math.pow(16, i)) {
-      var t = Math.floor(n / Math.pow(16, i));
-      n -= t * Math.pow(16, i);
-      if ( t >= 10 ) {
-        if ( t == 10 ) { h += "A"; }
-        if ( t == 11 ) { h += "B"; }
-        if ( t == 12 ) { h += "C"; }
-        if ( t == 13 ) { h += "D"; }
-        if ( t == 14 ) { h += "E"; }
-        if ( t == 15 ) { h += "F"; }
-      } else {
-        h += String(t);
-      }
-    } else {
-      h += "0";
-    }
-  }
-  return h;
-}
diff --git a/test/built-ins/decodeURIComponent/S15.1.3.2_A2.3_T1.js b/test/built-ins/decodeURIComponent/S15.1.3.2_A2.3_T1.js
index 2d40ec6644..14edea9c3b 100644
--- a/test/built-ins/decodeURIComponent/S15.1.3.2_A2.3_T1.js
+++ b/test/built-ins/decodeURIComponent/S15.1.3.2_A2.3_T1.js
@@ -7,6 +7,7 @@ info: >
     B1 = [0xC0, 0xC1], return UTF8(B1, B2)
 es5id: 15.1.3.2_A2.3_T1
 description: Complex tests, use RFC 3629
+includes: [decimalToHexString.js]
 ---*/
 
 var errorCount = 0;
@@ -15,16 +16,13 @@ var indexP;
 var indexO = 0;
 
 for (var indexB1 = 0xC2; indexB1 <= 0xDF; indexB1++) {
-  var hexB1 = decimalToHexString(indexB1);
+  var hexB1 = decimalToPercentHexString(indexB1);
   for (var indexB2 = 0x80; indexB2 <= 0xBF; indexB2++) {
     count++;
-    var hexB2 = decimalToHexString(indexB2);
+    var hexB1_B2 = hexB1 + decimalToPercentHexString(indexB2);
     var index = (indexB1 & 0x1F) * 0x40 + (indexB2 & 0x3F);  
-    try {
-      if (decodeURIComponent("%" + hexB1.substring(2) + "%" + hexB2.substring(2)) === String.fromCharCode(index)) continue;
-    } catch (e) {
-      if (e instanceof Test262Error) throw e;
-    }   
+    if (decodeURIComponent(hexB1_B2) === String.fromCharCode(index)) continue;
+
     if (indexO === 0) { 
       indexO = index;
     } else {
@@ -57,27 +55,3 @@ if (errorCount > 0) {
   }     
   $ERROR('Total error: ' + errorCount + ' bad Unicode character in ' + count + ' ');
 }
-
-function decimalToHexString(n) {
-  n = Number(n);
-  var h = "";
-  for (var i = 3; i >= 0; i--) {
-    if (n >= Math.pow(16, i)) {
-      var t = Math.floor(n / Math.pow(16, i));
-      n -= t * Math.pow(16, i);
-      if ( t >= 10 ) {
-        if ( t == 10 ) { h += "A"; }
-        if ( t == 11 ) { h += "B"; }
-        if ( t == 12 ) { h += "C"; }
-        if ( t == 13 ) { h += "D"; }
-        if ( t == 14 ) { h += "E"; }
-        if ( t == 15 ) { h += "F"; }
-      } else {
-        h += String(t);
-      }
-    } else {
-      h += "0";
-    }
-  }
-  return h;
-}
diff --git a/test/built-ins/decodeURIComponent/S15.1.3.2_A2.4_T1.js b/test/built-ins/decodeURIComponent/S15.1.3.2_A2.4_T1.js
index 03adf9a89e..8c6678e8f6 100644
--- a/test/built-ins/decodeURIComponent/S15.1.3.2_A2.4_T1.js
+++ b/test/built-ins/decodeURIComponent/S15.1.3.2_A2.4_T1.js
@@ -8,6 +8,7 @@ info: >
     0xDFFF), return UTF8(B1, B2, B3)
 es5id: 15.1.3.2_A2.4_T1
 description: Complex tests, use RFC 3629
+includes: [decimalToHexString.js]
 ---*/
 
 var errorCount = 0;
@@ -16,20 +17,17 @@ var indexP;
 var indexO = 0;
 
 for (var indexB1 = 0xE0; indexB1 <= 0xEF; indexB1++) {
-  var hexB1 = decimalToHexString(indexB1);
+  var hexB1 = decimalToPercentHexString(indexB1);
   for (var indexB2 = 0x80; indexB2 <= 0xBF; indexB2++) {
     if ((indexB1 === 0xE0) && (indexB2 <= 0x9F)) continue;
     if ((indexB1 === 0xED) && (0xA0 <= indexB2)) continue;         
-    var hexB2 = decimalToHexString(indexB2);
+    var hexB1_B2 = hexB1 + decimalToPercentHexString(indexB2);
     for (var indexB3 = 0x80; indexB3 <= 0xBF; indexB3++) {
       count++;
-      var hexB3 = decimalToHexString(indexB3);
+      var hexB1_B2_B3 = hexB1_B2 + decimalToPercentHexString(indexB3);
       var index = (indexB1 & 0x0F) * 0x1000 + (indexB2 & 0x3F) * 0x40 + (indexB3 & 0x3F);  
-      try {
-        if (decodeURIComponent("%" + hexB1.substring(2) + "%" + hexB2.substring(2) + "%" + hexB3.substring(2)) === String.fromCharCode(index)) continue;
-      } catch (e) {
-        if (e instanceof Test262Error) throw e;
-      }
+      if (decodeURIComponent(hexB1_B2_B3) === String.fromCharCode(index)) continue;
+
       if (indexO === 0) { 
         indexO = index;
       } else {
@@ -63,27 +61,3 @@ if (errorCount > 0) {
   }     
   $ERROR('Total error: ' + errorCount + ' bad Unicode character in ' + count + ' ');
 }
-
-function decimalToHexString(n) {
-  n = Number(n);
-  var h = "";
-  for (var i = 3; i >= 0; i--) {
-    if (n >= Math.pow(16, i)) {
-      var t = Math.floor(n / Math.pow(16, i));
-      n -= t * Math.pow(16, i);
-      if ( t >= 10 ) {
-        if ( t == 10 ) { h += "A"; }
-        if ( t == 11 ) { h += "B"; }
-        if ( t == 12 ) { h += "C"; }
-        if ( t == 13 ) { h += "D"; }
-        if ( t == 14 ) { h += "E"; }
-        if ( t == 15 ) { h += "F"; }
-      } else {
-        h += String(t);
-      }
-    } else {
-      h += "0";
-    }
-  }
-  return h;
-}
diff --git a/test/built-ins/decodeURIComponent/S15.1.3.2_A2.5_T1.js b/test/built-ins/decodeURIComponent/S15.1.3.2_A2.5_T1.js
index 6a2d55ae71..42cbda2245 100644
--- a/test/built-ins/decodeURIComponent/S15.1.3.2_A2.5_T1.js
+++ b/test/built-ins/decodeURIComponent/S15.1.3.2_A2.5_T1.js
@@ -8,6 +8,7 @@ info: >
     return UTF8(B1, B2, B3, B4)
 es5id: 15.1.3.2_A2.5_T1
 description: Complex tests, use RFC 3629
+includes: [decimalToHexString.js]
 ---*/
 
 var errorCount = 0;
@@ -16,24 +17,21 @@ var indexP;
 var indexO = 0;
 
 for (var indexB1 = 0xF0; indexB1 <= 0xF4; indexB1++) {
-  var hexB1 = decimalToHexString(indexB1);
+  var hexB1 = decimalToPercentHexString(indexB1);
   for (var indexB2 = 0x80; indexB2 <= 0xBF; indexB2++) {
     if ((indexB1 === 0xF0) && (indexB2 <= 0x9F)) continue;            
     if ((indexB1 === 0xF4) && (indexB2 >= 0x90)) continue;
-    var hexB2 = decimalToHexString(indexB2);
+    var hexB1_B2 = hexB1 + decimalToPercentHexString(indexB2);
     for (var indexB3 = 0x80; indexB3 <= 0xBF; indexB3++) {
-      var hexB3 = decimalToHexString(indexB3);
+      var hexB1_B2_B3 = hexB1_B2 + decimalToPercentHexString(indexB3);
       for (var indexB4 = 0x80; indexB4 <= 0xBF; indexB4++) {
-        var hexB4 = decimalToHexString(indexB4);
+        var hexB1_B2_B3_B4 = hexB1_B2_B3 + decimalToPercentHexString(indexB4);
         count++;
         var index = (indexB1 & 0x07) * 0x40000 + (indexB2 & 0x3F) * 0x1000 + (indexB3 & 0x3F) * 0x40 + (indexB4 & 0x3F);
         var L = ((index - 0x10000) & 0x03FF) + 0xDC00;
         var H = (((index - 0x10000) >> 10) & 0x03FF) + 0xD800;  
-        try {
-          if (decodeURIComponent("%" + hexB1.substring(3) + "%" + hexB2.substring(3) + "%" + hexB3.substring(3) + "%" + hexB4.substring(3)) === String.fromCharCode(H) + String.fromCharCode(L)) continue;
-        } catch (e) {
-          if (e instanceof Test262Error) throw e;
-        }   
+        if (decodeURIComponent(hexB1_B2_B3_B4) === String.fromCharCode(H, L)) continue;
+
         if (indexO === 0) { 
           indexO = index;
         } else {
@@ -68,27 +66,3 @@ if (errorCount > 0) {
   }     
   $ERROR('Total error: ' + errorCount + ' bad Unicode character in ' + count + ' ');
 }
-
-function decimalToHexString(n) {
-  n = Number(n);
-  var h = "";
-  for (var i = 4; i >= 0; i--) {
-    if (n >= Math.pow(16, i)) {
-      var t = Math.floor(n / Math.pow(16, i));
-      n -= t * Math.pow(16, i);
-      if ( t >= 10 ) {
-        if ( t == 10 ) { h += "A"; }
-        if ( t == 11 ) { h += "B"; }
-        if ( t == 12 ) { h += "C"; }
-        if ( t == 13 ) { h += "D"; }
-        if ( t == 14 ) { h += "E"; }
-        if ( t == 15 ) { h += "F"; }
-      } else {
-        h += String(t);
-      }
-    } else {
-      h += "0";
-    }
-  }
-  return h;
-}
diff --git a/test/built-ins/encodeURI/S15.1.3.3_A1.1_T1.js b/test/built-ins/encodeURI/S15.1.3.3_A1.1_T1.js
index 35da750488..781519c5eb 100644
--- a/test/built-ins/encodeURI/S15.1.3.3_A1.1_T1.js
+++ b/test/built-ins/encodeURI/S15.1.3.3_A1.1_T1.js
@@ -5,6 +5,7 @@
 info: If string.charAt(k) in [0xDC00 - 0xDFFF], throw URIError
 es5id: 15.1.3.3_A1.1_T1
 description: Complex tests
+includes: [decimalToHexString.js]
 ---*/
 
 var errorCount = 0;
@@ -51,27 +52,3 @@ if (errorCount > 0) {
   }     
   $ERROR('Total error: ' + errorCount + ' bad Unicode character in ' + count + ' ');
 }
-
-function decimalToHexString(n) {
-  n = Number(n);
-  var h = "";
-  for (var i = 3; i >= 0; i--) {
-    if (n >= Math.pow(16, i)) {
-      var t = Math.floor(n / Math.pow(16, i));
-      n -= t * Math.pow(16, i);
-      if ( t >= 10 ) {
-        if ( t == 10 ) { h += "A"; }
-        if ( t == 11 ) { h += "B"; }
-        if ( t == 12 ) { h += "C"; }
-        if ( t == 13 ) { h += "D"; }
-        if ( t == 14 ) { h += "E"; }
-        if ( t == 15 ) { h += "F"; }
-      } else {
-        h += String(t);
-      }
-    } else {
-      h += "0";
-    }
-  }
-  return h;
-}
diff --git a/test/built-ins/encodeURI/S15.1.3.3_A1.1_T2.js b/test/built-ins/encodeURI/S15.1.3.3_A1.1_T2.js
index b52327b992..0d3b4a9700 100644
--- a/test/built-ins/encodeURI/S15.1.3.3_A1.1_T2.js
+++ b/test/built-ins/encodeURI/S15.1.3.3_A1.1_T2.js
@@ -5,6 +5,7 @@
 info: If string.charAt(k) in [0xDC00 - 0xDFFF], throw URIError
 es5id: 15.1.3.3_A1.1_T2
 description: Complex tests
+includes: [decimalToHexString.js]
 ---*/
 
 var errorCount = 0;
@@ -51,27 +52,3 @@ if (errorCount > 0) {
   }     
   $ERROR('Total error: ' + errorCount + ' bad Unicode character in ' + count + ' ');
 }
-
-function decimalToHexString(n) {
-  n = Number(n);
-  var h = "";
-  for (var i = 3; i >= 0; i--) {
-    if (n >= Math.pow(16, i)) {
-      var t = Math.floor(n / Math.pow(16, i));
-      n -= t * Math.pow(16, i);
-      if ( t >= 10 ) {
-        if ( t == 10 ) { h += "A"; }
-        if ( t == 11 ) { h += "B"; }
-        if ( t == 12 ) { h += "C"; }
-        if ( t == 13 ) { h += "D"; }
-        if ( t == 14 ) { h += "E"; }
-        if ( t == 15 ) { h += "F"; }
-      } else {
-        h += String(t);
-      }
-    } else {
-      h += "0";
-    }
-  }
-  return h;
-}
diff --git a/test/built-ins/encodeURI/S15.1.3.3_A1.2_T1.js b/test/built-ins/encodeURI/S15.1.3.3_A1.2_T1.js
index 0180fd539e..26cb4751a0 100644
--- a/test/built-ins/encodeURI/S15.1.3.3_A1.2_T1.js
+++ b/test/built-ins/encodeURI/S15.1.3.3_A1.2_T1.js
@@ -7,6 +7,7 @@ info: >
     URIError
 es5id: 15.1.3.3_A1.2_T1
 description: Complex tests
+includes: [decimalToHexString.js]
 ---*/
 
 var errorCount = 0;
@@ -53,27 +54,3 @@ if (errorCount > 0) {
   }     
   $ERROR('Total error: ' + errorCount + ' bad Unicode character in ' + count + ' ');
 }
-
-function decimalToHexString(n) {
-  n = Number(n);
-  var h = "";
-  for (var i = 3; i >= 0; i--) {
-    if (n >= Math.pow(16, i)) {
-      var t = Math.floor(n / Math.pow(16, i));
-      n -= t * Math.pow(16, i);
-      if ( t >= 10 ) {
-        if ( t == 10 ) { h += "A"; }
-        if ( t == 11 ) { h += "B"; }
-        if ( t == 12 ) { h += "C"; }
-        if ( t == 13 ) { h += "D"; }
-        if ( t == 14 ) { h += "E"; }
-        if ( t == 15 ) { h += "F"; }
-      } else {
-        h += String(t);
-      }
-    } else {
-      h += "0";
-    }
-  }
-  return h;
-}
diff --git a/test/built-ins/encodeURI/S15.1.3.3_A1.2_T2.js b/test/built-ins/encodeURI/S15.1.3.3_A1.2_T2.js
index c23c66be6a..d55e3bfaff 100644
--- a/test/built-ins/encodeURI/S15.1.3.3_A1.2_T2.js
+++ b/test/built-ins/encodeURI/S15.1.3.3_A1.2_T2.js
@@ -7,6 +7,7 @@ info: >
     URIError
 es5id: 15.1.3.3_A1.2_T2
 description: Complex tests
+includes: [decimalToHexString.js]
 ---*/
 
 var errorCount = 0;
@@ -53,27 +54,3 @@ if (errorCount > 0) {
   }     
   $ERROR('Total error: ' + errorCount + ' bad Unicode character in ' + count + ' ');
 }
-
-function decimalToHexString(n) {
-  n = Number(n);
-  var h = "";
-  for (var i = 3; i >= 0; i--) {
-    if (n >= Math.pow(16, i)) {
-      var t = Math.floor(n / Math.pow(16, i));
-      n -= t * Math.pow(16, i);
-      if ( t >= 10 ) {
-        if ( t == 10 ) { h += "A"; }
-        if ( t == 11 ) { h += "B"; }
-        if ( t == 12 ) { h += "C"; }
-        if ( t == 13 ) { h += "D"; }
-        if ( t == 14 ) { h += "E"; }
-        if ( t == 15 ) { h += "F"; }
-      } else {
-        h += String(t);
-      }
-    } else {
-      h += "0";
-    }
-  }
-  return h;
-}
diff --git a/test/built-ins/encodeURI/S15.1.3.3_A1.3_T1.js b/test/built-ins/encodeURI/S15.1.3.3_A1.3_T1.js
index 20ffa34377..74acbdace1 100644
--- a/test/built-ins/encodeURI/S15.1.3.3_A1.3_T1.js
+++ b/test/built-ins/encodeURI/S15.1.3.3_A1.3_T1.js
@@ -9,6 +9,7 @@ es5id: 15.1.3.3_A1.3_T1
 description: >
     Complex tests, string.charAt(k+1) in [0x0000, 0xD7FF, 0xD800,
     0xDBFE, 0xDBFF, 0xE000, 0xFFFF]
+includes: [decimalToHexString.js]
 ---*/
 
 var chars = [0x0000, 0xD7FF, 0xD800, 0xDBFE, 0xDBFF, 0xE000, 0xFFFF];
@@ -62,27 +63,3 @@ if (errorCount > 0) {
   }     
   $ERROR('Total error: ' + errorCount + ' bad Unicode character in ' + count + ' ');
 }
-
-function decimalToHexString(n) {
-  n = Number(n);
-  var h = "";
-  for (var i = 3; i >= 0; i--) {
-    if (n >= Math.pow(16, i)) {
-      var t = Math.floor(n / Math.pow(16, i));
-      n -= t * Math.pow(16, i);
-      if ( t >= 10 ) {
-        if ( t == 10 ) { h += "A"; }
-        if ( t == 11 ) { h += "B"; }
-        if ( t == 12 ) { h += "C"; }
-        if ( t == 13 ) { h += "D"; }
-        if ( t == 14 ) { h += "E"; }
-        if ( t == 15 ) { h += "F"; }
-      } else {
-        h += String(t);
-      }
-    } else {
-      h += "0";
-    }
-  }
-  return h;
-}
diff --git a/test/built-ins/encodeURI/S15.1.3.3_A2.1_T1.js b/test/built-ins/encodeURI/S15.1.3.3_A2.1_T1.js
index 9cbd48a4bb..7074472ac5 100644
--- a/test/built-ins/encodeURI/S15.1.3.3_A2.1_T1.js
+++ b/test/built-ins/encodeURI/S15.1.3.3_A2.1_T1.js
@@ -7,6 +7,7 @@ info: >
     return 1 octet (00000000 0zzzzzzz -> 0zzzzzzz)
 es5id: 15.1.3.3_A2.1_T1
 description: Complex tests, use RFC 3629
+includes: [decimalToHexString.js]
 ---*/
 
 var uriReserved = [";", "/", "?", ":", "@", "&", "=", "+", "$", ","];
@@ -27,9 +28,8 @@ for (var index = 0x0000; index <= 0x007F; index++) {
     if (uriUnescaped[indexC] === str) continue l;
   }    
   if ("#" === str) continue l; 
-  try {
-    if (encodeURI(str).toUpperCase() === "%" + decimalToHexString(index).substring(2)) continue l; 
-  } catch(e) {}     
+  if (encodeURI(str).toUpperCase() === decimalToPercentHexString(index)) continue l;
+
   if (indexO === 0) { 
     indexO = index;
   } else {
@@ -61,27 +61,3 @@ if (errorCount > 0) {
   }     
   $ERROR('Total error: ' + errorCount + ' bad Unicode character in ' + count + ' ');
 }
-
-function decimalToHexString(n) {
-  n = Number(n);
-  var h = "";
-  for (var i = 3; i >= 0; i--) {
-    if (n >= Math.pow(16, i)) {
-      var t = Math.floor(n / Math.pow(16, i));
-      n -= t * Math.pow(16, i);
-      if ( t >= 10 ) {
-        if ( t == 10 ) { h += "A"; }
-        if ( t == 11 ) { h += "B"; }
-        if ( t == 12 ) { h += "C"; }
-        if ( t == 13 ) { h += "D"; }
-        if ( t == 14 ) { h += "E"; }
-        if ( t == 15 ) { h += "F"; }
-      } else {
-        h += String(t);
-      }
-    } else {
-      h += "0";
-    }
-  }
-  return h;
-}
diff --git a/test/built-ins/encodeURI/S15.1.3.3_A2.2_T1.js b/test/built-ins/encodeURI/S15.1.3.3_A2.2_T1.js
index 32d069d8c6..e293339abe 100644
--- a/test/built-ins/encodeURI/S15.1.3.3_A2.2_T1.js
+++ b/test/built-ins/encodeURI/S15.1.3.3_A2.2_T1.js
@@ -7,6 +7,7 @@ info: >
     yyzzzzzz -> 110yyyyy 10zzzzzz)
 es5id: 15.1.3.3_A2.2_T1
 description: Complex tests, use RFC 3629
+includes: [decimalToHexString.js]
 ---*/
 
 var errorCount = 0;
@@ -16,12 +17,11 @@ var indexO = 0;
 l:
 for (var index = 0x0080; index <= 0x07FF; index++) {
   count++;  
-  var hex1 = decimalToHexString(0x0080 + (index & 0x003F)).substring(2);
-  var hex2 = decimalToHexString(0x00C0 + (index & 0x07C0) / 0x0040).substring(2);
+  var hex1 = decimalToPercentHexString(0x0080 + (index & 0x003F));
+  var hex2 = decimalToPercentHexString(0x00C0 + (index & 0x07C0) / 0x0040);
   var str = String.fromCharCode(index);
-  try {
-    if (encodeURI(str).toUpperCase() === "%" + hex2 + "%" + hex1) continue;
-  } catch(e) {}  
+  if (encodeURI(str).toUpperCase() === hex2 + hex1) continue;
+
   if (indexO === 0) { 
     indexO = index;
   } else {
@@ -53,27 +53,3 @@ if (errorCount > 0) {
   }     
   $ERROR('Total error: ' + errorCount + ' bad Unicode character in ' + count + ' ');
 }
-
-function decimalToHexString(n) {
-  n = Number(n);
-  var h = "";
-  for (var i = 3; i >= 0; i--) {
-    if (n >= Math.pow(16, i)) {
-      var t = Math.floor(n / Math.pow(16, i));
-      n -= t * Math.pow(16, i);
-      if ( t >= 10 ) {
-        if ( t == 10 ) { h += "A"; }
-        if ( t == 11 ) { h += "B"; }
-        if ( t == 12 ) { h += "C"; }
-        if ( t == 13 ) { h += "D"; }
-        if ( t == 14 ) { h += "E"; }
-        if ( t == 15 ) { h += "F"; }
-      } else {
-        h += String(t);
-      }
-    } else {
-      h += "0";
-    }
-  }
-  return h;
-}
diff --git a/test/built-ins/encodeURI/S15.1.3.3_A2.3_T1.js b/test/built-ins/encodeURI/S15.1.3.3_A2.3_T1.js
index 9a6588fab1..c12383a20f 100644
--- a/test/built-ins/encodeURI/S15.1.3.3_A2.3_T1.js
+++ b/test/built-ins/encodeURI/S15.1.3.3_A2.3_T1.js
@@ -7,6 +7,7 @@ info: >
     yyzzzzzz -> 1110xxxx 10yyyyyy 10zzzzzz)
 es5id: 15.1.3.3_A2.3_T1
 description: Complex tests, use RFC 3629
+includes: [decimalToHexString.js]
 ---*/
 
 var errorCount = 0;
@@ -15,13 +16,12 @@ var indexP;
 var indexO = 0; 
 for (var index = 0x0800; index <= 0xD7FF; index++) {
   count++; 
-  var hex1 = decimalToHexString(0x0080 + (index & 0x003F)).substring(2);
-  var hex2 = decimalToHexString(0x0080 + (index & 0x0FC0) / 0x0040).substring(2);
-  var hex3 = decimalToHexString(0x00E0 + (index & 0xF000) / 0x1000).substring(2);
+  var hex1 = decimalToPercentHexString(0x0080 + (index & 0x003F));
+  var hex2 = decimalToPercentHexString(0x0080 + (index & 0x0FC0) / 0x0040);
+  var hex3 = decimalToPercentHexString(0x00E0 + (index & 0xF000) / 0x1000);
   var str = String.fromCharCode(index);
-  try {
-    if (encodeURI(str).toUpperCase() === "%" + hex3 + "%" + hex2 + "%" + hex1) continue;
-  } catch(e) {}      
+  if (encodeURI(str).toUpperCase() === hex3 + hex2 + hex1) continue;
+
   if (indexO === 0) { 
     indexO = index;
   } else {
@@ -53,27 +53,3 @@ if (errorCount > 0) {
   }     
   $ERROR('Total error: ' + errorCount + ' bad Unicode character in ' + count + ' ');
 }
-
-function decimalToHexString(n) {
-  n = Number(n);
-  var h = "";
-  for (var i = 3; i >= 0; i--) {
-    if (n >= Math.pow(16, i)) {
-      var t = Math.floor(n / Math.pow(16, i));
-      n -= t * Math.pow(16, i);
-      if ( t >= 10 ) {
-        if ( t == 10 ) { h += "A"; }
-        if ( t == 11 ) { h += "B"; }
-        if ( t == 12 ) { h += "C"; }
-        if ( t == 13 ) { h += "D"; }
-        if ( t == 14 ) { h += "E"; }
-        if ( t == 15 ) { h += "F"; }
-      } else {
-        h += String(t);
-      }
-    } else {
-      h += "0";
-    }
-  }
-  return h;
-}
diff --git a/test/built-ins/encodeURI/S15.1.3.3_A2.4_T1.js b/test/built-ins/encodeURI/S15.1.3.3_A2.4_T1.js
index 7c98072e49..838b038bde 100644
--- a/test/built-ins/encodeURI/S15.1.3.3_A2.4_T1.js
+++ b/test/built-ins/encodeURI/S15.1.3.3_A2.4_T1.js
@@ -10,6 +10,7 @@ es5id: 15.1.3.3_A2.4_T1
 description: >
     Complex tests, use RFC 3629, string.charAt(k+1) in [0xDC00,
     0xDDFF, 0xDFFF]
+includes: [decimalToHexString.js]
 ---*/
 
 var chars = [0xDC00, 0xDDFF, 0xDFFF];
@@ -21,16 +22,14 @@ for (var index = 0xD800; index <= 0xDBFF; index++) {
   var res = true;
   for (var indexC = 0; indexC < chars.length; indexC++) {
     var index1 = (index - 0xD800) * 0x400 + (chars[indexC] - 0xDC00) + 0x10000;
-    var hex1 = decimalToHexString(0x0080 + (index1 & 0x003F)).substring(2);
-    var hex2 = decimalToHexString(0x0080 + (index1 & 0x0FC0) / 0x0040).substring(2);
-    var hex3 = decimalToHexString(0x0080 + (index1 & 0x3F000) / 0x1000).substring(2);
-    var hex4 = decimalToHexString(0x00F0 + (index1 & 0x1C0000) / 0x40000).substring(2);
+    var hex1 = decimalToPercentHexString(0x0080 + (index1 & 0x003F));
+    var hex2 = decimalToPercentHexString(0x0080 + (index1 & 0x0FC0) / 0x0040);
+    var hex3 = decimalToPercentHexString(0x0080 + (index1 & 0x3F000) / 0x1000);
+    var hex4 = decimalToPercentHexString(0x00F0 + (index1 & 0x1C0000) / 0x40000);
     var str = String.fromCharCode(index, chars[indexC]);
-    try {
-      if (encodeURI(str).toUpperCase() !== "%" + hex4 + "%" + hex3 + "%" + hex2 + "%" + hex1) {
-        res = false;
-      }
-    } catch(e) {res = false}    
+    if (encodeURI(str).toUpperCase() === hex4 + hex3 + hex2 + hex1) continue;
+
+    res = false;
   }
   if (res !== true) {  
     if (indexO === 0) { 
@@ -66,27 +65,3 @@ if (errorCount > 0) {
   }     
   $ERROR('Total error: ' + errorCount + ' bad Unicode character in ' + count + ' ');
 }
-
-function decimalToHexString(n) {
-  n = Number(n);
-  var h = "";
-  for (var i = 3; i >= 0; i--) {
-    if (n >= Math.pow(16, i)) {
-      var t = Math.floor(n / Math.pow(16, i));
-      n -= t * Math.pow(16, i);
-      if ( t >= 10 ) {
-        if ( t == 10 ) { h += "A"; }
-        if ( t == 11 ) { h += "B"; }
-        if ( t == 12 ) { h += "C"; }
-        if ( t == 13 ) { h += "D"; }
-        if ( t == 14 ) { h += "E"; }
-        if ( t == 15 ) { h += "F"; }
-      } else {
-        h += String(t);
-      }
-    } else {
-      h += "0";
-    }
-  }
-  return h;
-}
diff --git a/test/built-ins/encodeURI/S15.1.3.3_A2.4_T2.js b/test/built-ins/encodeURI/S15.1.3.3_A2.4_T2.js
index 45887396eb..9d6643f908 100644
--- a/test/built-ins/encodeURI/S15.1.3.3_A2.4_T2.js
+++ b/test/built-ins/encodeURI/S15.1.3.3_A2.4_T2.js
@@ -10,6 +10,7 @@ es5id: 15.1.3.3_A2.4_T2
 description: >
     Complex tests, use RFC 3629, string.charAt(k) in [0xD800, 0xDBFF,
     0xD9FF]
+includes: [decimalToHexString.js]
 ---*/
 
 var chars = [0xD800, 0xDBFF, 0xD9FF];
@@ -21,16 +22,14 @@ for (var index = 0xDC00; index <= 0xDFFF; index++) {
   var res = true;
   for (var indexC = 0; indexC < chars.length; indexC++) {
     var index1 = (chars[indexC] - 0xD800) * 0x400 + (index - 0xDC00) + 0x10000;
-    var hex1 = decimalToHexString(0x0080 + (index1 & 0x003F)).substring(2);
-    var hex2 = decimalToHexString(0x0080 + (index1 & 0x0FC0) / 0x0040).substring(2);
-    var hex3 = decimalToHexString(0x0080 + (index1 & 0x3F000) / 0x1000).substring(2);
-    var hex4 = decimalToHexString(0x00F0 + (index1 & 0x1C0000) / 0x40000).substring(2);
+    var hex1 = decimalToPercentHexString(0x0080 + (index1 & 0x003F));
+    var hex2 = decimalToPercentHexString(0x0080 + (index1 & 0x0FC0) / 0x0040);
+    var hex3 = decimalToPercentHexString(0x0080 + (index1 & 0x3F000) / 0x1000);
+    var hex4 = decimalToPercentHexString(0x00F0 + (index1 & 0x1C0000) / 0x40000);
     var str = String.fromCharCode(chars[indexC], index);
-    try {
-      if (encodeURI(str).toUpperCase() !== "%" + hex4 + "%" + hex3 + "%" + hex2 + "%" + hex1) {
-        res = false;
-      }
-    } catch(e) {res = false}    
+    if (encodeURI(str).toUpperCase() === hex4 + hex3 + hex2 + hex1) continue;
+
+    res = false;
   }
   if (res !== true) {  
     if (indexO === 0) { 
@@ -66,27 +65,3 @@ if (errorCount > 0) {
   }     
   $ERROR('Total error: ' + errorCount + ' bad Unicode character in ' + count + ' ');
 }
-
-function decimalToHexString(n) {
-  n = Number(n);
-  var h = "";
-  for (var i = 3; i >= 0; i--) {
-    if (n >= Math.pow(16, i)) {
-      var t = Math.floor(n / Math.pow(16, i));
-      n -= t * Math.pow(16, i);
-      if ( t >= 10 ) {
-        if ( t == 10 ) { h += "A"; }
-        if ( t == 11 ) { h += "B"; }
-        if ( t == 12 ) { h += "C"; }
-        if ( t == 13 ) { h += "D"; }
-        if ( t == 14 ) { h += "E"; }
-        if ( t == 15 ) { h += "F"; }
-      } else {
-        h += String(t);
-      }
-    } else {
-      h += "0";
-    }
-  }
-  return h;
-}
diff --git a/test/built-ins/encodeURI/S15.1.3.3_A2.5_T1.js b/test/built-ins/encodeURI/S15.1.3.3_A2.5_T1.js
index cf21872824..21bd6e5a55 100644
--- a/test/built-ins/encodeURI/S15.1.3.3_A2.5_T1.js
+++ b/test/built-ins/encodeURI/S15.1.3.3_A2.5_T1.js
@@ -7,6 +7,7 @@ info: >
     yyzzzzzz -> 1110xxxx 10yyyyyy 10zzzzzz)
 es5id: 15.1.3.3_A2.5_T1
 description: Complex tests, use RFC 3629
+includes: [decimalToHexString.js]
 ---*/
 
 var errorCount = 0;
@@ -15,13 +16,12 @@ var indexP;
 var indexO = 0; 
 for (var index = 0xE000; index <= 0xFFFF; index++) {
   count++;  
-  var hex1 = decimalToHexString(0x0080 + (index & 0x003F)).substring(2);
-  var hex2 = decimalToHexString(0x0080 + (index & 0x0FC0) / 0x0040).substring(2);
-  var hex3 = decimalToHexString(0x00E0 + (index & 0xF000) / 0x1000).substring(2);
+  var hex1 = decimalToPercentHexString(0x0080 + (index & 0x003F));
+  var hex2 = decimalToPercentHexString(0x0080 + (index & 0x0FC0) / 0x0040);
+  var hex3 = decimalToPercentHexString(0x00E0 + (index & 0xF000) / 0x1000);
   var str = String.fromCharCode(index);
-  try {
-    if (encodeURI(str).toUpperCase() === "%" + hex3 + "%" + hex2 + "%" + hex1) continue;
-  } catch(e) {}      
+  if (encodeURI(str).toUpperCase() === hex3 + hex2 + hex1) continue;
+
   if (indexO === 0) { 
     indexO = index;
   } else {
@@ -53,27 +53,3 @@ if (errorCount > 0) {
   }     
   $ERROR('Total error: ' + errorCount + ' bad Unicode character in ' + count + ' ');
 }
-
-function decimalToHexString(n) {
-  n = Number(n);
-  var h = "";
-  for (var i = 3; i >= 0; i--) {
-    if (n >= Math.pow(16, i)) {
-      var t = Math.floor(n / Math.pow(16, i));
-      n -= t * Math.pow(16, i);
-      if ( t >= 10 ) {
-        if ( t == 10 ) { h += "A"; }
-        if ( t == 11 ) { h += "B"; }
-        if ( t == 12 ) { h += "C"; }
-        if ( t == 13 ) { h += "D"; }
-        if ( t == 14 ) { h += "E"; }
-        if ( t == 15 ) { h += "F"; }
-      } else {
-        h += String(t);
-      }
-    } else {
-      h += "0";
-    }
-  }
-  return h;
-}
diff --git a/test/built-ins/encodeURIComponent/S15.1.3.4_A1.1_T1.js b/test/built-ins/encodeURIComponent/S15.1.3.4_A1.1_T1.js
index 99fd5ae1e0..3e16943a2a 100644
--- a/test/built-ins/encodeURIComponent/S15.1.3.4_A1.1_T1.js
+++ b/test/built-ins/encodeURIComponent/S15.1.3.4_A1.1_T1.js
@@ -5,6 +5,7 @@
 info: If string.charAt(k) in [0xDC00 - 0xDFFF], throw URIError
 es5id: 15.1.3.4_A1.1_T1
 description: Complex tests
+includes: [decimalToHexString.js]
 ---*/
 
 var errorCount = 0;
@@ -51,27 +52,3 @@ if (errorCount > 0) {
   }     
   $ERROR('Total error: ' + errorCount + ' bad Unicode character in ' + count + ' ');
 }
-
-function decimalToHexString(n) {
-  n = Number(n);
-  var h = "";
-  for (var i = 3; i >= 0; i--) {
-    if (n >= Math.pow(16, i)) {
-      var t = Math.floor(n / Math.pow(16, i));
-      n -= t * Math.pow(16, i);
-      if ( t >= 10 ) {
-        if ( t == 10 ) { h += "A"; }
-        if ( t == 11 ) { h += "B"; }
-        if ( t == 12 ) { h += "C"; }
-        if ( t == 13 ) { h += "D"; }
-        if ( t == 14 ) { h += "E"; }
-        if ( t == 15 ) { h += "F"; }
-      } else {
-        h += String(t);
-      }
-    } else {
-      h += "0";
-    }
-  }
-  return h;
-}
diff --git a/test/built-ins/encodeURIComponent/S15.1.3.4_A1.1_T2.js b/test/built-ins/encodeURIComponent/S15.1.3.4_A1.1_T2.js
index ba5316447e..a5cf69ae0e 100644
--- a/test/built-ins/encodeURIComponent/S15.1.3.4_A1.1_T2.js
+++ b/test/built-ins/encodeURIComponent/S15.1.3.4_A1.1_T2.js
@@ -5,6 +5,7 @@
 info: If string.charAt(k) in [0xDC00 - 0xDFFF], throw URIError
 es5id: 15.1.3.4_A1.1_T2
 description: Complex tests
+includes: [decimalToHexString.js]
 ---*/
 
 var errorCount = 0;
@@ -51,27 +52,3 @@ if (errorCount > 0) {
   }     
   $ERROR('Total error: ' + errorCount + ' bad Unicode character in ' + count + ' ');
 }
-
-function decimalToHexString(n) {
-  n = Number(n);
-  var h = "";
-  for (var i = 3; i >= 0; i--) {
-    if (n >= Math.pow(16, i)) {
-      var t = Math.floor(n / Math.pow(16, i));
-      n -= t * Math.pow(16, i);
-      if ( t >= 10 ) {
-        if ( t == 10 ) { h += "A"; }
-        if ( t == 11 ) { h += "B"; }
-        if ( t == 12 ) { h += "C"; }
-        if ( t == 13 ) { h += "D"; }
-        if ( t == 14 ) { h += "E"; }
-        if ( t == 15 ) { h += "F"; }
-      } else {
-        h += String(t);
-      }
-    } else {
-      h += "0";
-    }
-  }
-  return h;
-}
diff --git a/test/built-ins/encodeURIComponent/S15.1.3.4_A1.2_T1.js b/test/built-ins/encodeURIComponent/S15.1.3.4_A1.2_T1.js
index 740356e676..99db50d9f8 100644
--- a/test/built-ins/encodeURIComponent/S15.1.3.4_A1.2_T1.js
+++ b/test/built-ins/encodeURIComponent/S15.1.3.4_A1.2_T1.js
@@ -7,6 +7,7 @@ info: >
     URIError
 es5id: 15.1.3.4_A1.2_T1
 description: Complex tests
+includes: [decimalToHexString.js]
 ---*/
 
 var errorCount = 0;
@@ -53,27 +54,3 @@ if (errorCount > 0) {
   }     
   $ERROR('Total error: ' + errorCount + ' bad Unicode character in ' + count + ' ');
 }
-
-function decimalToHexString(n) {
-  n = Number(n);
-  var h = "";
-  for (var i = 3; i >= 0; i--) {
-    if (n >= Math.pow(16, i)) {
-      var t = Math.floor(n / Math.pow(16, i));
-      n -= t * Math.pow(16, i);
-      if ( t >= 10 ) {
-        if ( t == 10 ) { h += "A"; }
-        if ( t == 11 ) { h += "B"; }
-        if ( t == 12 ) { h += "C"; }
-        if ( t == 13 ) { h += "D"; }
-        if ( t == 14 ) { h += "E"; }
-        if ( t == 15 ) { h += "F"; }
-      } else {
-        h += String(t);
-      }
-    } else {
-      h += "0";
-    }
-  }
-  return h;
-}
diff --git a/test/built-ins/encodeURIComponent/S15.1.3.4_A1.2_T2.js b/test/built-ins/encodeURIComponent/S15.1.3.4_A1.2_T2.js
index c60733689a..fb406d723c 100644
--- a/test/built-ins/encodeURIComponent/S15.1.3.4_A1.2_T2.js
+++ b/test/built-ins/encodeURIComponent/S15.1.3.4_A1.2_T2.js
@@ -7,6 +7,7 @@ info: >
     URIError
 es5id: 15.1.3.4_A1.2_T2
 description: Complex tests
+includes: [decimalToHexString.js]
 ---*/
 
 var errorCount = 0;
@@ -53,27 +54,3 @@ if (errorCount > 0) {
   }     
   $ERROR('Total error: ' + errorCount + ' bad Unicode character in ' + count + ' ');
 }
-
-function decimalToHexString(n) {
-  n = Number(n);
-  var h = "";
-  for (var i = 3; i >= 0; i--) {
-    if (n >= Math.pow(16, i)) {
-      var t = Math.floor(n / Math.pow(16, i));
-      n -= t * Math.pow(16, i);
-      if ( t >= 10 ) {
-        if ( t == 10 ) { h += "A"; }
-        if ( t == 11 ) { h += "B"; }
-        if ( t == 12 ) { h += "C"; }
-        if ( t == 13 ) { h += "D"; }
-        if ( t == 14 ) { h += "E"; }
-        if ( t == 15 ) { h += "F"; }
-      } else {
-        h += String(t);
-      }
-    } else {
-      h += "0";
-    }
-  }
-  return h;
-}
diff --git a/test/built-ins/encodeURIComponent/S15.1.3.4_A1.3_T1.js b/test/built-ins/encodeURIComponent/S15.1.3.4_A1.3_T1.js
index d63f0f3bc8..1338e6b589 100644
--- a/test/built-ins/encodeURIComponent/S15.1.3.4_A1.3_T1.js
+++ b/test/built-ins/encodeURIComponent/S15.1.3.4_A1.3_T1.js
@@ -9,6 +9,7 @@ es5id: 15.1.3.4_A1.3_T1
 description: >
     Complex tests, string.charAt(k+1) in [0x0000, 0xD7FF, 0xD800,
     0xDBFE, 0xDBFF, 0xE000, 0xFFFF]
+includes: [decimalToHexString.js]
 ---*/
 
 var chars = [0x0000, 0xD7FF, 0xD800, 0xDBFE, 0xDBFF, 0xE000, 0xFFFF];
@@ -62,27 +63,3 @@ if (errorCount > 0) {
   }     
   $ERROR('Total error: ' + errorCount + ' bad Unicode character in ' + count + ' ');
 }
-
-function decimalToHexString(n) {
-  n = Number(n);
-  var h = "";
-  for (var i = 3; i >= 0; i--) {
-    if (n >= Math.pow(16, i)) {
-      var t = Math.floor(n / Math.pow(16, i));
-      n -= t * Math.pow(16, i);
-      if ( t >= 10 ) {
-        if ( t == 10 ) { h += "A"; }
-        if ( t == 11 ) { h += "B"; }
-        if ( t == 12 ) { h += "C"; }
-        if ( t == 13 ) { h += "D"; }
-        if ( t == 14 ) { h += "E"; }
-        if ( t == 15 ) { h += "F"; }
-      } else {
-        h += String(t);
-      }
-    } else {
-      h += "0";
-    }
-  }
-  return h;
-}
diff --git a/test/built-ins/encodeURIComponent/S15.1.3.4_A2.1_T1.js b/test/built-ins/encodeURIComponent/S15.1.3.4_A2.1_T1.js
index 808dce688d..1f09fa39e0 100644
--- a/test/built-ins/encodeURIComponent/S15.1.3.4_A2.1_T1.js
+++ b/test/built-ins/encodeURIComponent/S15.1.3.4_A2.1_T1.js
@@ -7,6 +7,7 @@ info: >
     (00000000 0zzzzzzz -> 0zzzzzzz)
 es5id: 15.1.3.4_A2.1_T1
 description: Complex tests, use RFC 3629
+includes: [decimalToHexString.js]
 ---*/
 
 var uriUnescaped = ["-", "_", ".", "!", "~", "*", "'", "(", ")", "A", "B", "C", "D", "E", "F", "G", "H", "I", "J", "K", "L", "M", "N", "O", "P", "Q", "R", "S", "T", "U", "V", "W", "X", "Y", "Z", "a", "b", "c", "d", "e", "f", "g", "h", "i", "j", "k", "l", "m", "n", "o", "p", "q", "r", "s", "t", "u", "v", "w", "x", "y", "z", "0", "1", "2", "3", "4", "5", "6", "7", "8", "9"];
@@ -22,9 +23,8 @@ for (var index = 0x0000; index <= 0x007F; index++) {
     for (var indexC = 0; indexC < uriUnescaped.length; indexC++) {
     if (uriUnescaped[indexC] === str) continue l;
   }    
-  try {
-    if (encodeURIComponent(str).toUpperCase() === "%" + decimalToHexString(index).substring(2)) continue l; 
-  } catch(e) {}     
+  if (encodeURIComponent(str).toUpperCase() === decimalToPercentHexString(index)) continue l;
+
   if (indexO === 0) { 
     indexO = index;
   } else {
@@ -56,27 +56,3 @@ if (errorCount > 0) {
   }     
   $ERROR('Total error: ' + errorCount + ' bad Unicode character in ' + count + ' ');
 }
-
-function decimalToHexString(n) {
-  n = Number(n);
-  var h = "";
-  for (var i = 3; i >= 0; i--) {
-    if (n >= Math.pow(16, i)) {
-      var t = Math.floor(n / Math.pow(16, i));
-      n -= t * Math.pow(16, i);
-      if ( t >= 10 ) {
-        if ( t == 10 ) { h += "A"; }
-        if ( t == 11 ) { h += "B"; }
-        if ( t == 12 ) { h += "C"; }
-        if ( t == 13 ) { h += "D"; }
-        if ( t == 14 ) { h += "E"; }
-        if ( t == 15 ) { h += "F"; }
-      } else {
-        h += String(t);
-      }
-    } else {
-      h += "0";
-    }
-  }
-  return h;
-}
diff --git a/test/built-ins/encodeURIComponent/S15.1.3.4_A2.2_T1.js b/test/built-ins/encodeURIComponent/S15.1.3.4_A2.2_T1.js
index eccd3cdaa9..8ee2d440d0 100644
--- a/test/built-ins/encodeURIComponent/S15.1.3.4_A2.2_T1.js
+++ b/test/built-ins/encodeURIComponent/S15.1.3.4_A2.2_T1.js
@@ -7,6 +7,7 @@ info: >
     yyzzzzzz -> 110yyyyy 10zzzzzz)
 es5id: 15.1.3.4_A2.2_T1
 description: Complex tests, use RFC 3629
+includes: [decimalToHexString.js]
 ---*/
 
 var errorCount = 0;
@@ -16,12 +17,11 @@ var indexO = 0;
 l:
 for (var index = 0x0080; index <= 0x07FF; index++) {
   count++;  
-  var hex1 = decimalToHexString(0x0080 + (index & 0x003F)).substring(2);
-  var hex2 = decimalToHexString(0x00C0 + (index & 0x07C0) / 0x0040).substring(2);
+  var hex1 = decimalToPercentHexString(0x0080 + (index & 0x003F));
+  var hex2 = decimalToPercentHexString(0x00C0 + (index & 0x07C0) / 0x0040);
   var str = String.fromCharCode(index);
-  try {
-    if (encodeURIComponent(str).toUpperCase() === "%" + hex2 + "%" + hex1) continue;
-  } catch(e) {}  
+  if (encodeURIComponent(str).toUpperCase() === hex2 + hex1) continue;
+
   if (indexO === 0) { 
     indexO = index;
   } else {
@@ -53,27 +53,3 @@ if (errorCount > 0) {
   }     
   $ERROR('Total error: ' + errorCount + ' bad Unicode character in ' + count + ' ');
 }
-
-function decimalToHexString(n) {
-  n = Number(n);
-  var h = "";
-  for (var i = 3; i >= 0; i--) {
-    if (n >= Math.pow(16, i)) {
-      var t = Math.floor(n / Math.pow(16, i));
-      n -= t * Math.pow(16, i);
-      if ( t >= 10 ) {
-        if ( t == 10 ) { h += "A"; }
-        if ( t == 11 ) { h += "B"; }
-        if ( t == 12 ) { h += "C"; }
-        if ( t == 13 ) { h += "D"; }
-        if ( t == 14 ) { h += "E"; }
-        if ( t == 15 ) { h += "F"; }
-      } else {
-        h += String(t);
-      }
-    } else {
-      h += "0";
-    }
-  }
-  return h;
-}
diff --git a/test/built-ins/encodeURIComponent/S15.1.3.4_A2.3_T1.js b/test/built-ins/encodeURIComponent/S15.1.3.4_A2.3_T1.js
index 41ada6f405..c2dd431315 100644
--- a/test/built-ins/encodeURIComponent/S15.1.3.4_A2.3_T1.js
+++ b/test/built-ins/encodeURIComponent/S15.1.3.4_A2.3_T1.js
@@ -7,6 +7,7 @@ info: >
     yyzzzzzz -> 1110xxxx 10yyyyyy 10zzzzzz)
 es5id: 15.1.3.4_A2.3_T1
 description: Complex tests, use RFC 3629
+includes: [decimalToHexString.js]
 ---*/
 
 var errorCount = 0;
@@ -15,13 +16,12 @@ var indexP;
 var indexO = 0; 
 for (var index = 0x0800; index <= 0xD7FF; index++) {
   count++; 
-  var hex1 = decimalToHexString(0x0080 + (index & 0x003F)).substring(2);
-  var hex2 = decimalToHexString(0x0080 + (index & 0x0FC0) / 0x0040).substring(2);
-  var hex3 = decimalToHexString(0x00E0 + (index & 0xF000) / 0x1000).substring(2);
+  var hex1 = decimalToPercentHexString(0x0080 + (index & 0x003F));
+  var hex2 = decimalToPercentHexString(0x0080 + (index & 0x0FC0) / 0x0040);
+  var hex3 = decimalToPercentHexString(0x00E0 + (index & 0xF000) / 0x1000);
   var str = String.fromCharCode(index);
-  try {
-    if (encodeURIComponent(str).toUpperCase() === "%" + hex3 + "%" + hex2 + "%" + hex1) continue;
-  } catch(e) {}      
+  if (encodeURIComponent(str).toUpperCase() === hex3 + hex2 + hex1) continue;
+
   if (indexO === 0) { 
     indexO = index;
   } else {
@@ -53,27 +53,3 @@ if (errorCount > 0) {
   }     
   $ERROR('Total error: ' + errorCount + ' bad Unicode character in ' + count + ' ');
 }
-
-function decimalToHexString(n) {
-  n = Number(n);
-  var h = "";
-  for (var i = 3; i >= 0; i--) {
-    if (n >= Math.pow(16, i)) {
-      var t = Math.floor(n / Math.pow(16, i));
-      n -= t * Math.pow(16, i);
-      if ( t >= 10 ) {
-        if ( t == 10 ) { h += "A"; }
-        if ( t == 11 ) { h += "B"; }
-        if ( t == 12 ) { h += "C"; }
-        if ( t == 13 ) { h += "D"; }
-        if ( t == 14 ) { h += "E"; }
-        if ( t == 15 ) { h += "F"; }
-      } else {
-        h += String(t);
-      }
-    } else {
-      h += "0";
-    }
-  }
-  return h;
-}
diff --git a/test/built-ins/encodeURIComponent/S15.1.3.4_A2.4_T1.js b/test/built-ins/encodeURIComponent/S15.1.3.4_A2.4_T1.js
index bb7ba1ddb6..94164c98c1 100644
--- a/test/built-ins/encodeURIComponent/S15.1.3.4_A2.4_T1.js
+++ b/test/built-ins/encodeURIComponent/S15.1.3.4_A2.4_T1.js
@@ -10,6 +10,7 @@ es5id: 15.1.3.4_A2.4_T1
 description: >
     Complex tests, use RFC 3629, string.charAt(k+1) in [0xDC00,
     0xDDFF, 0xDFFF]
+includes: [decimalToHexString.js]
 ---*/
 
 var chars = [0xDC00, 0xDDFF, 0xDFFF];
@@ -21,16 +22,14 @@ for (var index = 0xD800; index <= 0xDBFF; index++) {
   var res = true;
   for (var indexC = 0; indexC < chars.length; indexC++) {
     var index1 = (index - 0xD800) * 0x400 + (chars[indexC] - 0xDC00) + 0x10000;
-    var hex1 = decimalToHexString(0x0080 + (index1 & 0x003F)).substring(2);
-    var hex2 = decimalToHexString(0x0080 + (index1 & 0x0FC0) / 0x0040).substring(2);
-    var hex3 = decimalToHexString(0x0080 + (index1 & 0x3F000) / 0x1000).substring(2);
-    var hex4 = decimalToHexString(0x00F0 + (index1 & 0x1C0000) / 0x40000).substring(2);
+    var hex1 = decimalToPercentHexString(0x0080 + (index1 & 0x003F));
+    var hex2 = decimalToPercentHexString(0x0080 + (index1 & 0x0FC0) / 0x0040);
+    var hex3 = decimalToPercentHexString(0x0080 + (index1 & 0x3F000) / 0x1000);
+    var hex4 = decimalToPercentHexString(0x00F0 + (index1 & 0x1C0000) / 0x40000);
     var str = String.fromCharCode(index, chars[indexC]);
-    try {
-      if (encodeURIComponent(str).toUpperCase() !== "%" + hex4 + "%" + hex3 + "%" + hex2 + "%" + hex1) {
-        res = false;
-      }
-    } catch(e) {res = false}    
+    if (encodeURIComponent(str).toUpperCase() === hex4 + hex3 + hex2 + hex1) continue;
+
+    res = false;
   }
   if (res !== true) {  
     if (indexO === 0) { 
@@ -66,27 +65,3 @@ if (errorCount > 0) {
   }     
   $ERROR('Total error: ' + errorCount + ' bad Unicode character in ' + count + ' ');
 }
-
-function decimalToHexString(n) {
-  n = Number(n);
-  var h = "";
-  for (var i = 3; i >= 0; i--) {
-    if (n >= Math.pow(16, i)) {
-      var t = Math.floor(n / Math.pow(16, i));
-      n -= t * Math.pow(16, i);
-      if ( t >= 10 ) {
-        if ( t == 10 ) { h += "A"; }
-        if ( t == 11 ) { h += "B"; }
-        if ( t == 12 ) { h += "C"; }
-        if ( t == 13 ) { h += "D"; }
-        if ( t == 14 ) { h += "E"; }
-        if ( t == 15 ) { h += "F"; }
-      } else {
-        h += String(t);
-      }
-    } else {
-      h += "0";
-    }
-  }
-  return h;
-}
diff --git a/test/built-ins/encodeURIComponent/S15.1.3.4_A2.4_T2.js b/test/built-ins/encodeURIComponent/S15.1.3.4_A2.4_T2.js
index 9ff448ecba..3fd3d0a4c2 100644
--- a/test/built-ins/encodeURIComponent/S15.1.3.4_A2.4_T2.js
+++ b/test/built-ins/encodeURIComponent/S15.1.3.4_A2.4_T2.js
@@ -10,6 +10,7 @@ es5id: 15.1.3.4_A2.4_T2
 description: >
     Complex tests, use RFC 3629, string.charAt(k) in [0xD800, 0xDBFF,
     0xD9FF]
+includes: [decimalToHexString.js]
 ---*/
 
 var chars = [0xD800, 0xDBFF, 0xD9FF];
@@ -21,16 +22,14 @@ for (var index = 0xDC00; index <= 0xDFFF; index++) {
   var res = true;
   for (var indexC = 0; indexC < chars.length; indexC++) {
     var index1 = (chars[indexC] - 0xD800) * 0x400 + (index - 0xDC00) + 0x10000;
-    var hex1 = decimalToHexString(0x0080 + (index1 & 0x003F)).substring(2);
-    var hex2 = decimalToHexString(0x0080 + (index1 & 0x0FC0) / 0x0040).substring(2);
-    var hex3 = decimalToHexString(0x0080 + (index1 & 0x3F000) / 0x1000).substring(2);
-    var hex4 = decimalToHexString(0x00F0 + (index1 & 0x1C0000) / 0x40000).substring(2);
+    var hex1 = decimalToPercentHexString(0x0080 + (index1 & 0x003F));
+    var hex2 = decimalToPercentHexString(0x0080 + (index1 & 0x0FC0) / 0x0040);
+    var hex3 = decimalToPercentHexString(0x0080 + (index1 & 0x3F000) / 0x1000);
+    var hex4 = decimalToPercentHexString(0x00F0 + (index1 & 0x1C0000) / 0x40000);
     var str = String.fromCharCode(chars[indexC], index);
-    try {
-      if (encodeURIComponent(str).toUpperCase() !== "%" + hex4 + "%" + hex3 + "%" + hex2 + "%" + hex1) {
-        res = false;
-      }
-    } catch(e) {res = false}    
+    if (encodeURIComponent(str).toUpperCase() === hex4 + hex3 + hex2 + hex1) continue;
+
+    res = false;
   }
   if (res !== true) {  
     if (indexO === 0) { 
@@ -66,27 +65,3 @@ if (errorCount > 0) {
   }     
   $ERROR('Total error: ' + errorCount + ' bad Unicode character in ' + count + ' ');
 }
-
-function decimalToHexString(n) {
-  n = Number(n);
-  var h = "";
-  for (var i = 3; i >= 0; i--) {
-    if (n >= Math.pow(16, i)) {
-      var t = Math.floor(n / Math.pow(16, i));
-      n -= t * Math.pow(16, i);
-      if ( t >= 10 ) {
-        if ( t == 10 ) { h += "A"; }
-        if ( t == 11 ) { h += "B"; }
-        if ( t == 12 ) { h += "C"; }
-        if ( t == 13 ) { h += "D"; }
-        if ( t == 14 ) { h += "E"; }
-        if ( t == 15 ) { h += "F"; }
-      } else {
-        h += String(t);
-      }
-    } else {
-      h += "0";
-    }
-  }
-  return h;
-}
diff --git a/test/built-ins/encodeURIComponent/S15.1.3.4_A2.5_T1.js b/test/built-ins/encodeURIComponent/S15.1.3.4_A2.5_T1.js
index 22f7445e79..2f68bcf052 100644
--- a/test/built-ins/encodeURIComponent/S15.1.3.4_A2.5_T1.js
+++ b/test/built-ins/encodeURIComponent/S15.1.3.4_A2.5_T1.js
@@ -7,6 +7,7 @@ info: >
     yyzzzzzz -> 1110xxxx 10yyyyyy 10zzzzzz)
 es5id: 15.1.3.4_A2.5_T1
 description: Complex tests, use RFC 3629
+includes: [decimalToHexString.js]
 ---*/
 
 var errorCount = 0;
@@ -15,13 +16,12 @@ var indexP;
 var indexO = 0; 
 for (var index = 0xE000; index <= 0xFFFF; index++) {
   count++;  
-  var hex1 = decimalToHexString(0x0080 + (index & 0x003F)).substring(2);
-  var hex2 = decimalToHexString(0x0080 + (index & 0x0FC0) / 0x0040).substring(2);
-  var hex3 = decimalToHexString(0x00E0 + (index & 0xF000) / 0x1000).substring(2);
+  var hex1 = decimalToPercentHexString(0x0080 + (index & 0x003F));
+  var hex2 = decimalToPercentHexString(0x0080 + (index & 0x0FC0) / 0x0040);
+  var hex3 = decimalToPercentHexString(0x00E0 + (index & 0xF000) / 0x1000);
   var str = String.fromCharCode(index);
-  try {
-    if (encodeURIComponent(str).toUpperCase() === "%" + hex3 + "%" + hex2 + "%" + hex1) continue;
-  } catch(e) {}      
+  if (encodeURIComponent(str).toUpperCase() === hex3 + hex2 + hex1) continue;
+
   if (indexO === 0) { 
     indexO = index;
   } else {
@@ -53,27 +53,3 @@ if (errorCount > 0) {
   }     
   $ERROR('Total error: ' + errorCount + ' bad Unicode character in ' + count + ' ');
 }
-
-function decimalToHexString(n) {
-  n = Number(n);
-  var h = "";
-  for (var i = 3; i >= 0; i--) {
-    if (n >= Math.pow(16, i)) {
-      var t = Math.floor(n / Math.pow(16, i));
-      n -= t * Math.pow(16, i);
-      if ( t >= 10 ) {
-        if ( t == 10 ) { h += "A"; }
-        if ( t == 11 ) { h += "B"; }
-        if ( t == 12 ) { h += "C"; }
-        if ( t == 13 ) { h += "D"; }
-        if ( t == 14 ) { h += "E"; }
-        if ( t == 15 ) { h += "F"; }
-      } else {
-        h += String(t);
-      }
-    } else {
-      h += "0";
-    }
-  }
-  return h;
-}
diff --git a/test/built-ins/parseFloat/S15.1.2.3_A6.js b/test/built-ins/parseFloat/S15.1.2.3_A6.js
index a9983ac278..a1fc0eead0 100644
--- a/test/built-ins/parseFloat/S15.1.2.3_A6.js
+++ b/test/built-ins/parseFloat/S15.1.2.3_A6.js
@@ -9,6 +9,7 @@ info: >
     characters were ignored.
 es5id: 15.1.2.3_A6
 description: Complex test without eval
+includes: [decimalToHexString.js]
 ---*/
 
 //CHECK
@@ -54,27 +55,3 @@ if (errorCount > 0) {
   }     
   $ERROR('Total error: ' + errorCount + ' bad Unicode character in ' + count + ' ');
 }
-
-function decimalToHexString(n) {
-  n = Number(n);
-  var h = "";
-  for (var i = 3; i >= 0; i--) {
-    if (n >= Math.pow(16, i)) {
-      var t = Math.floor(n / Math.pow(16, i));
-      n -= t * Math.pow(16, i);
-      if ( t >= 10 ) {
-        if ( t == 10 ) { h += "A"; }
-        if ( t == 11 ) { h += "B"; }
-        if ( t == 12 ) { h += "C"; }
-        if ( t == 13 ) { h += "D"; }
-        if ( t == 14 ) { h += "E"; }
-        if ( t == 15 ) { h += "F"; }
-      } else {
-        h += String(t);
-      }
-    } else {
-      h += "0";
-    }
-  }
-  return h;
-}
diff --git a/test/built-ins/parseInt/S15.1.2.2_A8.js b/test/built-ins/parseInt/S15.1.2.2_A8.js
index 5aabbdedd8..030c7b67d7 100644
--- a/test/built-ins/parseInt/S15.1.2.2_A8.js
+++ b/test/built-ins/parseInt/S15.1.2.2_A8.js
@@ -9,6 +9,7 @@ info: >
     characters were ignored.
 es5id: 15.1.2.2_A8
 description: Complex test without eval
+includes: [decimalToHexString.js]
 ---*/
 
 //CHECK
@@ -56,27 +57,3 @@ if (errorCount > 0) {
   }     
   $ERROR('Total error: ' + errorCount + ' bad Unicode character in ' + count + ' ');
 }
-
-function decimalToHexString(n) {
-  n = Number(n);
-  var h = "";
-  for (var i = 3; i >= 0; i--) {
-    if (n >= Math.pow(16, i)) {
-      var t = Math.floor(n / Math.pow(16, i));
-      n -= t * Math.pow(16, i);
-      if ( t >= 10 ) {
-        if ( t == 10 ) { h += "A"; }
-        if ( t == 11 ) { h += "B"; }
-        if ( t == 12 ) { h += "C"; }
-        if ( t == 13 ) { h += "D"; }
-        if ( t == 14 ) { h += "E"; }
-        if ( t == 15 ) { h += "F"; }
-      } else {
-        h += String(t);
-      }
-    } else {
-      h += "0";
-    }
-  }
-  return h;
-}