Add tests for object coercion of Reference base (#646)

Occurs that when a PutValue or GetValue operation is applied to a
property reference with a primitive base, the base is first coerced to
an Object.

test/language/types/reference/get-value-prop-base-primitive.js

@@ -0,0 +1,29 @@
+// Copyright (C) 2016 the V8 project authors. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+/*---
+esid: sec-getvalue
+es6id: 6.2.3.1
+description: >
+  When the base of a property reference is primitive, it is coerced to an
+  object during value retrieval
+info: >
+  [...]
+  5. If IsPropertyReference(V) is true, then
+     a. If HasPrimitiveBase(V) is true, then
+        i. Assert: In this case, base will never be null or undefined.
+        ii. Let base be ToObject(base).
+     b. Return ? base.[[Get]](GetReferencedName(V), GetThisValue(V)).
+features: [Symbol]
+---*/
+
+Number.prototype.test262 = 'number prototype';
+assert.sameValue(1..test262, 'number prototype');
+
+String.prototype.test262 = 'string prototype';
+assert.sameValue(''.test262, 'string prototype');
+
+Boolean.prototype.test262 = 'Boolean prototype';
+assert.sameValue(true.test262, 'Boolean prototype');
+
+Symbol.prototype.test262 = 'Symbol prototype';
+assert.sameValue(Symbol().test262, 'Symbol prototype');

test/language/types/reference/put-value-prop-base-primitive.js

@@ -0,0 +1,47 @@
+// Copyright (C) 2016 the V8 project authors. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+/*---
+esid: sec-putvalue
+es6id: 6.2.3.2
+description: >
+  When the base of a property reference is primitive, it is coerced to an
+  object during value assignment
+info: >
+  [...]
+  6. Else if IsPropertyReference(V) is true, then
+     a. If HasPrimitiveBase(V) is true, then
+        i. Assert: In this case, base will never be null or undefined.
+        ii. Set base to ToObject(base).
+     b. Let succeeded be ? base.[[Set]](GetReferencedName(V), W,
+        GetThisValue(V)).
+     c. If succeeded is false and IsStrictReference(V) is true, throw a
+        TypeError exception.
+     d. Return.
+features: [Symbol, Proxy]
+---*/
+
+var numberCount = 0;
+var stringCount = 0;
+var booleanCount = 0;
+var symbolCount = 0;
+var spy;
+
+spy = new Proxy({}, { set: function() { numberCount += 1; return true; } });
+Object.setPrototypeOf(Number.prototype, spy);
+0..test262 = null;
+assert.sameValue(numberCount, 1, 'number');
+
+spy = new Proxy({}, { set: function() { stringCount += 1; return true; } });
+Object.setPrototypeOf(String.prototype, spy);
+''.test262 = null;
+assert.sameValue(stringCount, 1, 'string');
+
+spy = new Proxy({}, { set: function() { booleanCount += 1; return true; } });
+Object.setPrototypeOf(Boolean.prototype, spy);
+true.test262 = null;
+assert.sameValue(booleanCount, 1, 'string');
+
+spy = new Proxy({}, { set: function() { symbolCount += 1; return true; } });
+Object.setPrototypeOf(Symbol.prototype, spy);
+Symbol().test262 = null;
+assert.sameValue(symbolCount, 1, 'string');