Increase coverage for for..of iteration

test/language/statements/for-of/body-dstr-assign-error.js

@@ -0,0 +1,39 @@
+// Copyright (C) 2015 the V8 project authors. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+/*---
+es6id: 13.6.4.13 S5.i.i
+description: >
+    If the left-hand side requires a DestructuringAssignment operation and that
+    operation produces an error, the iterator should be closed and the error
+    forwarded to the runtime.
+features: [Symbol.iterator]
+---*/
+
+var callCount = 0;
+var iterationCount = 0;
+var iterable = {};
+var x = {
+  set attr(_) {
+    throw new Test262Error();
+  }
+};
+
+iterable[Symbol.iterator] = function() {
+  return {
+    next: function() {
+      return { done: false, value: [0] };
+    },
+    return: function() {
+      callCount += 1;
+    }
+  }
+};
+
+assert.throws(Test262Error, function() {
+  for ([x.attr] of iterable) {
+    iterationCount += 1;
+  }
+});
+
+assert.sameValue(iterationCount, 0, 'The loop body is not evaluated');
+assert.sameValue(callCount, 1, 'Iterator is closed');

test/language/statements/for-of/body-dstr-assign.js

@@ -0,0 +1,17 @@
+// Copyright (C) 2015 the V8 project authors. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+/*---
+es6id: 13.6.4.13 S5.i.i
+description: >
+    The left-hand side may take the form of a DestructuringAssignment.
+---*/
+
+var iterationCount = 0;
+var x;
+
+for ([x] of [[0]]) {
+  assert.sameValue(x, 0);
+  iterationCount += 1;
+}
+
+assert.sameValue(iterationCount, 1);

test/language/statements/for-of/body-put-error.js

@@ -0,0 +1,39 @@
+// Copyright (C) 2015 the V8 project authors. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+/*---
+es6id: 13.6.4.13 S5.h.ii
+description: >
+    If the left-hand side is not a lexical binding and the assignment produces
+    an error, the iterator should be closed and the error forwarded to the
+    runtime.
+features: [Symbol.iterator]
+---*/
+
+var callCount = 0;
+var iterationCount = 0;
+var iterable = {};
+var x = {
+  set attr(_) {
+    throw new Test262Error();
+  }
+};
+
+iterable[Symbol.iterator] = function() {
+  return {
+    next: function() {
+      return { done: false, value: 0 };
+    },
+    return: function() {
+      callCount += 1;
+    }
+  }
+};
+
+assert.throws(Test262Error, function() {
+  for (x.attr of iterable) {
+    iterationCount += 1;
+  }
+});
+
+assert.sameValue(iterationCount, 0, 'The loop body is not evaluated');
+assert.sameValue(callCount, 1, 'Iterator is closed');

test/language/statements/for-of/generator-close-via-break.js

@@ -0,0 +1,47 @@
+// Copyright (C) 2015 the V8 project authors. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+/*---
+es6id: 13.6.4.13
+description: >
+    Generators should be closed via their `return` method when iteration is
+    interrupted via a `break` statement.
+features: [generators]
+---*/
+
+var startedCount = 0;
+var finallyCount = 0;
+var iterationCount = 0;
+function* values() {
+  startedCount += 1;
+  try {
+    yield;
+    $ERROR('This code is unreachable (within `try` block)');
+  } finally {
+    finallyCount += 1;
+  }
+  $ERROR('This code is unreachable (following `try` statement)');
+}
+var iterable = values();
+
+assert.sameValue(
+  startedCount, 0, 'Generator is initialized in suspended state'
+);
+
+for (var x of iterable) {
+  assert.sameValue(
+    startedCount, 1, 'Generator executes prior to first iteration'
+  );
+  assert.sameValue(
+    finallyCount, 0, 'Generator is paused during first iteration'
+  );
+  iterationCount += 1;
+  break;
+}
+
+assert.sameValue(
+  startedCount, 1, 'Generator does not restart following interruption'
+);
+assert.sameValue(iterationCount, 1, 'A single iteration occurs');
+assert.sameValue(
+  finallyCount, 1, 'Generator is closed after `break` statement'
+);

test/language/statements/for-of/generator-close-via-return.js

@@ -0,0 +1,49 @@
+// Copyright (C) 2015 the V8 project authors. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+/*---
+es6id: 13.6.4.13
+description: >
+    Generators should be closed via their `return` method when iteration is
+    interrupted via a `return` statement.
+features: [generators]
+---*/
+
+var startedCount = 0;
+var finallyCount = 0;
+var iterationCount = 0;
+function* values() {
+  startedCount += 1;
+  try {
+    yield;
+    $ERROR('This code is unreachable (within `try` block)');
+  } finally {
+    finallyCount += 1;
+  }
+  $ERROR('This code is unreachable (following `try` statement)');
+}
+var iterable = values();
+
+assert.sameValue(
+  startedCount, 0, 'Generator is initialized in suspended state'
+);
+
+(function() {
+  for (var x of iterable) {
+    assert.sameValue(
+      startedCount, 1, 'Generator executes prior to first iteration'
+    );
+    assert.sameValue(
+      finallyCount, 0, 'Generator is paused during first iteration'
+    );
+    iterationCount += 1;
+    return;
+  }
+}());
+
+assert.sameValue(
+  startedCount, 1, 'Generator does not restart following interruption'
+);
+assert.sameValue(iterationCount, 1, 'A single iteration occurs');
+assert.sameValue(
+  finallyCount, 1, 'Generator is closed after `return` statement'
+);

test/language/statements/for-of/generator-close-via-throw.js

@@ -0,0 +1,49 @@
+// Copyright (C) 2015 the V8 project authors. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+/*---
+es6id: 13.6.4.13
+description: >
+    Generators should be closed via their `return` method when iteration is
+    interrupted via a `throw` statement.
+features: [generators]
+---*/
+
+var startedCount = 0;
+var finallyCount = 0;
+var iterationCount = 0;
+function* values() {
+  startedCount += 1;
+  try {
+    yield;
+    $ERROR('This code is unreachable (within `try` block)');
+  } finally {
+    finallyCount += 1;
+  }
+  $ERROR('This code is unreachable (following `try` statement)');
+}
+var iterable = values();
+
+assert.sameValue(
+  startedCount, 0, 'Generator is initialized in suspended state'
+);
+
+try {
+  for (var x of iterable) {
+    assert.sameValue(
+      startedCount, 1, 'Generator executes prior to first iteration'
+    );
+    assert.sameValue(
+      finallyCount, 0, 'Generator is paused during first iteration'
+    );
+    iterationCount += 1;
+    throw 0;
+  }
+} catch(err) {}
+
+assert.sameValue(
+  startedCount, 1, 'Generator does not restart following interruption'
+);
+assert.sameValue(iterationCount, 1, 'A single iteration occurs');
+assert.sameValue(
+  finallyCount, 1, 'Generator is closed after `throw` statement'
+);

test/language/statements/for-of/generator-next-error.js

@@ -0,0 +1,22 @@
+// Copyright (C) 2015 the V8 project authors. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+/*---
+es6id: 13.6.4.13 S5.g
+description: >
+    If `nextResult` is an abrupt completion as per IteratorStep (ES6 7.4.5),
+    return the completion.
+features: [generators]
+---*/
+
+var iterable = (function*() {
+  throw new Test262Error();
+}());
+var iterationCount = 0;
+
+assert.throws(Test262Error, function() {
+  for (var x of iterable) {
+    iterationCount += 1;
+  }
+});
+
+assert.sameValue(iterationCount, 0, 'The loop body is not evaluated');

test/language/statements/for-of/iterator-close-get-method-error.js

@@ -0,0 +1,32 @@
+// Copyright (C) 2015 the V8 project authors. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+/*---
+es6id: 13.6.4.13
+description: >
+    If retrieving an iterator's `return` method generates an error while
+    closing the iterator, the error should be forwarded to the runtime.
+features: [Symbol.iterator]
+---*/
+
+var iterable = {};
+var iterationCount = 0;
+
+iterable[Symbol.iterator] = function() {
+  return {
+    next: function() {
+      return { done: false, value: null };
+    },
+    get return() {
+      throw new Test262Error();
+    }
+  };
+};
+
+assert.throws(Test262Error, function() {
+  for (var x of iterable) {
+    iterationCount += 1;
+    break;
+  }
+});
+
+assert.sameValue(iterationCount, 1, 'The loop body is evaluated');

test/language/statements/for-of/iterator-close-non-object.js

@@ -0,0 +1,32 @@
+// Copyright (C) 2015 the V8 project authors. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+/*---
+es6id: 13.6.4.13
+description: >
+    If an iterator's `return` method returns a non-Object value, a TypeError
+    should be thrown.
+features: [Symbol.iterator]
+---*/
+
+var iterable = {};
+var iterationCount = 0;
+
+iterable[Symbol.iterator] = function() {
+  return {
+    next: function() {
+      return { done: false, value: null };
+    },
+    return: function() {
+      return 0;
+    }
+  };
+};
+
+assert.throws(TypeError, function() {
+  for (var x of iterable) {
+    iterationCount += 1;
+    break;
+  }
+});
+
+assert.sameValue(iterationCount, 1, 'The loop body is evaluated');

test/language/statements/for-of/iterator-close-via-break.js

@@ -0,0 +1,46 @@
+// Copyright (C) 2015 the V8 project authors. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+/*---
+es6id: 13.6.4.13
+description: >
+    Iterators should be closed via their `return` method when iteration is
+    interrupted via a `break` statement.
+features: [Symbol.iterator]
+---*/
+
+var startedCount = 0;
+var returnCount = 0;
+var iterationCount = 0;
+var iterable = {};
+
+iterable[Symbol.iterator] = function() {
+  return {
+    next: function() {
+      startedCount += 1;
+      return { done: false, value: null };
+    },
+    return: function() {
+      returnCount += 1;
+      return {};
+    }
+  };
+};
+
+for (var x of iterable) {
+  assert.sameValue(
+    startedCount, 1, 'Value is retrieved'
+  );
+  assert.sameValue(
+    returnCount, 0, 'Iterator is not closed'
+  );
+  iterationCount += 1;
+  break;
+}
+
+assert.sameValue(
+  startedCount, 1, 'Iterator does not restart following interruption'
+);
+assert.sameValue(iterationCount, 1, 'A single iteration occurs');
+assert.sameValue(
+  returnCount, 1, 'Iterator is closed after `break` statement'
+);

test/language/statements/for-of/iterator-close-via-return.js

@@ -0,0 +1,48 @@
+// Copyright (C) 2015 the V8 project authors. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+/*---
+es6id: 13.6.4.13
+description: >
+    Iterators should be closed via their `return` method when iteration is
+    interrupted via a `return` statement.
+features: [Symbol.iterator]
+---*/
+
+var startedCount = 0;
+var returnCount = 0;
+var iterationCount = 0;
+var iterable = {};
+
+iterable[Symbol.iterator] = function() {
+  return {
+    next: function() {
+      startedCount += 1;
+      return { done: false, value: null };
+    },
+    return: function() {
+      returnCount += 1;
+      return {};
+    }
+  };
+};
+
+(function() {
+  for (var x of iterable) {
+    assert.sameValue(
+      startedCount, 1, 'Value is retrieved'
+    );
+    assert.sameValue(
+      returnCount, 0, 'Iterator is not closed'
+    );
+    iterationCount += 1;
+    return;
+  }
+}());
+
+assert.sameValue(
+  startedCount, 1, 'Iterator does not restart following interruption'
+);
+assert.sameValue(iterationCount, 1, 'A single iteration occurs');
+assert.sameValue(
+  returnCount, 1, 'Iterator is closed after `return` statement'
+);

test/language/statements/for-of/iterator-close-via-throw.js

@@ -0,0 +1,48 @@
+// Copyright (C) 2015 the V8 project authors. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+/*---
+es6id: 13.6.4.13
+description: >
+    Iterators should be closed via their `return` method when iteration is
+    interrupted via a `throw` statement.
+features: [Symbol.iterator]
+---*/
+
+var startedCount = 0;
+var returnCount = 0;
+var iterationCount = 0;
+var iterable = {};
+
+iterable[Symbol.iterator] = function() {
+  return {
+    next: function() {
+      startedCount += 1;
+      return { done: false, value: null };
+    },
+    return: function() {
+      returnCount += 1;
+      return {};
+    }
+  };
+};
+
+try {
+  for (var x of iterable) {
+    assert.sameValue(
+      startedCount, 1, 'Value is retrieved'
+    );
+    assert.sameValue(
+      returnCount, 0, 'Iterator is not closed'
+    );
+    iterationCount += 1;
+    throw 0;
+  }
+} catch (err) {}
+
+assert.sameValue(
+  startedCount, 1, 'Iterator does not restart following interruption'
+);
+assert.sameValue(iterationCount, 1, 'A single iteration occurs');
+assert.sameValue(
+  returnCount, 1, 'Iterator is closed after `throw` statement'
+);

test/language/statements/for-of/iterator-next-error.js

@@ -0,0 +1,28 @@
+// Copyright (C) 2015 the V8 project authors. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+/*---
+es6id: 13.6.4.13 S5.d
+description: >
+    If `nextResult` is an abrupt completion as per IteratorStep (ES6 7.4.5),
+    return the completion.
+features: [Symbol.iterator]
+---*/
+
+var iterable = {};
+var iterationCount = 0;
+
+iterable[Symbol.iterator] = function() {
+  return {
+    next: function() {
+      throw new Test262Error();
+    }
+  };
+};
+
+assert.throws(Test262Error, function() {
+  for (var x of iterable) {
+    iterationCount += 1;
+  }
+});
+
+assert.sameValue(iterationCount, 0, 'The loop body is not evaluated');

test/language/statements/for-of/iterator-next-result-value-attr-error.js

@@ -0,0 +1,33 @@
+// Copyright (C) 2015 the V8 project authors. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+/*---
+es6id: 13.6.4.13 S5.g
+description: >
+    If `nextValue` is an abrupt completion as per IteratorValue (ES6 7.4.4),
+    return the completion.
+features: [Symbol.iterator]
+---*/
+
+var iterable = {};
+var iterationCount = 0;
+
+iterable[Symbol.iterator] = function() {
+  return {
+    next: function() {
+      return {
+        done: false,
+        get value() {
+          throw new Test262Error();
+        }
+      };
+    }
+  };
+};
+
+assert.throws(Test262Error, function() {
+  for (var x of iterable) {
+    iterationCount += 1;
+  }
+});
+
+assert.sameValue(iterationCount, 0, 'The loop body is not evaluated');