Add tests for GeneratorPrototype#return

Implement tests according to the pattern defined by the existing tests
for `GeneratorPrototype#throw`.

test/built-ins/GeneratorPrototype/return/from-state-completed.js

@@ -0,0 +1,21 @@
+// Copyright (C) 2014 the V8 project authors. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+/*---
+es6id: 25.3.1.3
+description: >
+    Resuming abruptly from a generator in the 'completed' state should honor the
+    abrupt completion and remain in the 'completed' state.
+---*/
+
+function* G() {}
+var iter, result;
+
+iter = G();
+iter.next();
+
+iter.return(33);
+
+result = iter.next();
+
+assert.sameValue(result.value, undefined, 'Result `value`');
+assert.sameValue(result.done, true, 'Result `done` flag');

test/built-ins/GeneratorPrototype/return/from-state-executing.js

@@ -0,0 +1,18 @@
+// Copyright (C) 2015 the V8 project authors. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+/*---
+es6id: 25.3.3.2
+description: >
+    A TypeError should be thrown if the generator is resumed abruptly while
+    running.
+---*/
+
+var iter;
+function* g() {
+  iter.return(42);
+}
+
+iter = g();
+assert.throws(TypeError, function() {
+  iter.next();
+});

test/built-ins/GeneratorPrototype/return/from-state-suspended-start.js

@@ -0,0 +1,25 @@
+// Copyright (C) 2014 the V8 project authors. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+/*---
+es6id: 25.3.1.3
+description: >
+    Resuming abruptly from a generator in the 'suspendedStart' state should
+    honor the abrupt completion and trigger a transition into the 'completed'
+    state.
+---*/
+
+function* G() {
+  yield 1;
+}
+var iter = G();
+var result;
+
+result = iter.return(56);
+
+assert.sameValue(result.value, 56);
+assert.sameValue(result.done, true);
+
+result = iter.next();
+
+assert.sameValue(result.value, undefined, 'Result `value`');
+assert.sameValue(result.done, true, 'Result `done` flag');

test/built-ins/GeneratorPrototype/return/incorrect-context.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: 25.3.1.3
+description: >
+    A TypeError should be thrown from GeneratorValidate (25.3.3.2) if the
+    context of `return` does not defined the [[GeneratorState]] internal slot.
+---*/
+
+function* g() {}
+var GeneratorPrototype = Object.getPrototypeOf(g).prototype;
+
+assert.throws(TypeError, function() { GeneratorPrototype.return.call(1); });
+assert.throws(TypeError, function() { GeneratorPrototype.return.call({}); });
+assert.throws(TypeError, function() { GeneratorPrototype.return.call(function() {}); });
+assert.throws(TypeError, function() { GeneratorPrototype.return.call(g); });
+assert.throws(TypeError, function() { GeneratorPrototype.return.call(g.prototype); });

test/built-ins/GeneratorPrototype/return/property-descriptor.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.
+
+/*---
+description: >
+    The GeneratorPrototype intrinsic should define a `return` property that is
+    non-enumerable, writable, and configurable (as per section 17).
+includes: [propertyHelper.js]
+es6id: 25.3.1
+---*/
+
+function* g() {}
+var GeneratorPrototype = Object.getPrototypeOf(g).prototype;
+
+verifyNotEnumerable(GeneratorPrototype, 'return');
+verifyWritable(GeneratorPrototype, 'return');
+verifyConfigurable(GeneratorPrototype, 'return');

test/built-ins/GeneratorPrototype/return/try-catch-before-try.js

@@ -0,0 +1,35 @@
+// Copyright (C) 2015 the V8 project authors. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+/*---
+es6id: 25.3.1.3
+description: >
+    When a generator is paused before a `try..catch` statement, `return` should
+    interrupt control flow as if a `return` statement had appeared at that
+    location in the function body.
+---*/
+
+function* g() {
+  yield;
+  try {
+    $ERROR('This code is unreachable (within `try` block)');
+  } catch (e) {
+    throw e;
+  }
+  $ERROR('This code is unreachable (following `try` statement)');
+}
+var iter = g();
+var result;
+
+iter.next();
+
+result = iter.return(45);
+assert.sameValue(result.value, 45, 'Result `value` following `return`');
+assert.sameValue(result.done, true, 'Result `done` flag following `return`');
+
+result = iter.next();
+assert.sameValue(result.value,
+  undefined, 'Result `value` is undefined when complete'
+);
+assert.sameValue(
+  result.done, true, 'Result `done` flag is `true` when complete'
+);

test/built-ins/GeneratorPrototype/return/try-catch-following-catch.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: 25.3.1.3
+description: >
+    When a generator is paused after a `try..catch` statement, `return` should
+    interrupt control flow as if a `return` statement had appeared at that
+    location in the function body.
+---*/
+
+var afterCatch = false;
+function* g() {
+  try {
+    throw new Error();
+  } catch (e) {}
+  afterCatch = true;
+  yield;
+  $ERROR('This code is unreachable');
+}
+var iter = g();
+var result;
+
+result = iter.next();
+
+assert.sameValue(afterCatch, true);
+
+result = iter.return(45);
+assert.sameValue(
+  result.value, 45, 'Result `value` following `return`'
+);
+assert.sameValue(result.done, true, 'Result `done` flag following `return`');
+
+result = iter.next();
+assert.sameValue(
+  result.value, undefined, 'Result `value` is undefined when complete'
+);
+assert.sameValue(
+  result.done, true, 'Result `done` flag is `true` when complete'
+);

test/built-ins/GeneratorPrototype/return/try-catch-within-catch.js

@@ -0,0 +1,41 @@
+// Copyright (C) 2015 the V8 project authors. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+/*---
+es6id: 25.3.1.3
+description: >
+    When a generator is paused within the `catch` block of a `try..catch`
+    statement, `return` should interrupt control flow as if a `return`
+    statement had appeared at that location in the function body.
+---*/
+
+var inCatch = false;
+function* g() {
+  try {
+    throw new Error();
+  } catch (e) {
+    inCatch = true;
+    yield;
+    $ERROR('This code is unreachable (within `catch` block)');
+  }
+  $ERROR('This code is unreachable (following `try` statement)');
+}
+var iter = g();
+var result;
+
+result = iter.next();
+
+assert.sameValue(inCatch, true);
+
+result = iter.return(45);
+assert.sameValue(
+  result.value, 45, 'Result `value` following `return`'
+);
+assert.sameValue(result.done, true, 'Result `done` flag following `return`');
+
+result = iter.next();
+assert.sameValue(
+  result.value, undefined, 'Result `value` is undefined when complete'
+);
+assert.sameValue(
+  result.done, true, 'Result `done` flag is `true` when complete'
+);

test/built-ins/GeneratorPrototype/return/try-catch-within-try.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: 25.3.1.3
+description: >
+    When a generator is paused within the `try` block of a `try..catch`
+    statement, `return` should interrupt control flow as if a `return`
+    statement had appeared at that location in the function body.
+---*/
+
+var inTry = false;
+function* g() {
+  try {
+    inTry = true;
+    yield;
+    $ERROR('This code is unreachable (within `try` block)');
+  } catch (e) {
+    throw e;
+  }
+  $ERROR('This code is unreachable (following `try` statement)');
+}
+var iter = g();
+var result;
+
+result = iter.next();
+
+assert.sameValue(inTry, true);
+
+result = iter.return(44);
+assert.sameValue(result.value, 44, 'Result `value` following `return`');
+assert.sameValue(result.done, true, 'Result `done` flag following `return`');
+
+result = iter.next();
+assert.sameValue(
+  result.value, undefined, 'Result `value` is undefined when complete'
+);
+assert.sameValue(
+  result.done, true, 'Result `done` flag is `true` when complete'
+);

test/built-ins/GeneratorPrototype/return/try-finally-before-try.js

@@ -0,0 +1,35 @@
+// Copyright (C) 2015 the V8 project authors. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+/*---
+es6id: 25.3.1.3
+description: >
+    When a generator is paused before a `try..finally` statement, `return`
+    should interrupt control flow as if a `return` statement had appeared at
+    that location in the function body.
+---*/
+
+function* g() {
+  yield;
+  try {
+    $ERROR('This code is unreachable (within `try` block)');
+  } finally {
+    $ERROR('This code is unreachable (within `finally` block)');
+  }
+  $ERROR('This code is unreachable (following `try` statement)');
+}
+var iter = g();
+var result;
+
+iter.next();
+
+result = iter.return(45);
+assert.sameValue(result.value, 45, 'Result `value` following `return`');
+assert.sameValue(result.done, true, 'Result `done` flag following `return`');
+
+result = iter.next();
+assert.sameValue(
+  result.value, undefined, 'Result `value` is undefined when complete'
+);
+assert.sameValue(
+  result.done, true, 'Result `done` flag is `true` when complete'
+);

test/built-ins/GeneratorPrototype/return/try-finally-following-finally.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: 25.3.1.3
+description: >
+    When a generator is paused after a `try..finally` statement, `return`
+    should interrupt control flow as if a `return` statement had appeared at
+    that location in the function body.
+---*/
+
+var afterFinally = false;
+function* g() {
+  try {
+  } finally {}
+  afterFinally = true;
+  yield;
+}
+var iter = g();
+var result;
+
+iter.next();
+
+assert.sameValue(afterFinally, true);
+
+result = iter.return(45);
+assert.sameValue(result.value, 45, 'Result `value` following `return`');
+assert.sameValue(result.done, true, 'Result `done` flag following `return`');
+
+result = iter.next();
+assert.sameValue(
+  result.value, undefined, 'Result `value` is undefined when done'
+);
+assert.sameValue(result.done, true, 'Result `done` flag is `true` when done');

test/built-ins/GeneratorPrototype/return/try-finally-nested-try-catch-within-catch.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: 25.3.1.3
+description: >
+    When a generator is paused within a `catch` block that is declared within a
+    `try` block of a `try..catch` statement, `return` should interrupt control
+    flow as if a `return` statement had appeared at that location in the
+    function body.
+---*/
+
+var inCatch = false;
+var inFinally = false;
+function* g() {
+  try {
+    try {
+      throw new Error();
+    } catch (e) {
+      inCatch = true;
+      yield;
+      $ERROR('This code is unreachable (within `catch` block)');
+    }
+    $ERROR('This code is unreachable (following nested `try` statement)');
+  } finally {
+    inFinally = true;
+  }
+  $ERROR('This code is unreachable (following outer `try` statement)');
+}
+var iter = g();
+var result;
+
+result = iter.next();
+
+assert.sameValue(inCatch, true, '`catch` code patch executed');
+assert.sameValue(inFinally, false, '`finally` code path not executed');
+
+result = iter.return(45);
+assert.sameValue(result.value, 45, 'Result `value` following `return`');
+assert.sameValue(result.done, true, 'Result `done` flag following `return`');
+assert.sameValue(inFinally, true, '`finally` code path executed');
+
+result = iter.next();
+assert.sameValue(
+  result.value, undefined, 'Result `value` is undefined when complete'
+);
+assert.sameValue(
+  result.done, true, 'Result `done` flag is `true` when compelete'
+);

test/built-ins/GeneratorPrototype/return/try-finally-nested-try-catch-within-finally.js

@@ -0,0 +1,41 @@
+// Copyright (C) 2015 the V8 project authors. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+/*---
+es6id: 25.3.1.3
+description: >
+    When a generator is paused within a `finally` block of a `try..catch`
+    statement, `return` should interrupt control flow as if a `return`
+    statement had appeared at that location in the function body.
+---*/
+
+var inFinally = false;
+function* g() {
+  try {
+    throw new Error();
+    try {
+    } catch (e) {}
+  } finally {
+    inFinally = true;
+    yield;
+    $ERROR('This code is unreachable (within `finally` block)');
+  }
+  $ERROR('This code is unreachable (following outer `try` statement)');
+}
+var iter = g();
+var result;
+
+result = iter.next();
+
+assert.sameValue(inFinally, true, '`finally` code path executed');
+
+result = iter.return(45);
+assert.sameValue(result.value, 45, 'Result `value` following `return`');
+assert.sameValue(result.done, true, 'Result `done` flag following `return`');
+
+result = iter.next();
+assert.sameValue(
+  result.value, undefined, 'Result `value` is undefined when complete'
+);
+assert.sameValue(
+  result.done, true, 'Result `done` flag is `true` when complete'
+);

test/built-ins/GeneratorPrototype/return/try-finally-nested-try-catch-within-inner-try.js

@@ -0,0 +1,50 @@
+// Copyright (C) 2015 the V8 project authors. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+/*---
+es6id: 25.3.1.3
+description: >
+    When a generator is paused within a `try` block that is declared within a
+    `try` block of a `try..catch` statement, `return` should interrupt control
+    flow as if a `return` statement had appeared at that location in the
+    function body.
+---*/
+
+var inTry = false;
+var inFinally = false;
+function* g() {
+  try {
+    try {
+      inTry = true;
+      yield;
+      $ERROR('This code is unreachable (within nested `try` block)');
+    } catch (e) {
+      throw e;
+    }
+    $ERROR('This code is unreachable (following nested `try` statement)');
+  } finally {
+    inFinally = true;
+  }
+  $ERROR('This code is unreachable (following outer `try` statement)');
+}
+var iter = g();
+var exception = new Error();
+var result;
+
+iter.next();
+
+assert.sameValue(inTry, true, 'Nested `try` code patch executed');
+assert.sameValue(inFinally, false, '`finally` code path not executed');
+
+result = iter.return(45);
+
+assert.sameValue(result.value, 45, 'Result `value` following `return`');
+assert.sameValue(result.done, true, 'Result `done` flag following `return`');
+assert.sameValue(inFinally, true, '`finally` code path executed');
+
+result = iter.next();
+assert.sameValue(
+  result.value, undefined, 'Result `value` is undefined when complete'
+);
+assert.sameValue(
+  result.done, true, 'Result `done` flag is `true` when complete'
+);

test/built-ins/GeneratorPrototype/return/try-finally-nested-try-catch-within-outer-try-after-nested.js

@@ -0,0 +1,45 @@
+// Copyright (C) 2015 the V8 project authors. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+/*---
+es6id: 25.3.1.3
+description: >
+    When a generator is paused within a `try` block of a `try..catch` statement
+    and following a nested `try..catch` statment, `return` should interrupt
+    control flow as if a `return` statement had appeared at that location in
+    the function body.
+---*/
+
+var inCatch = false;
+var inFinally = false;
+function* g() {
+  try {
+    try {
+      throw new Error();
+    } catch (e) {
+      inCatch = true;
+    }
+  } finally {
+    inFinally = true;
+  }
+  yield;
+  $ERROR('This code is unreachable');
+}
+var iter = g();
+var result;
+
+ iter.next();
+
+assert.sameValue(inCatch, true, '`catch` code path executed');
+assert.sameValue(inFinally, true, '`finally` code path executed');
+
+result = iter.return(45);
+assert.sameValue(result.value, 45, 'Result `value` following `return`');
+assert.sameValue(result.done, true, 'Result `done` flag following `return`');
+
+result = iter.next();
+assert.sameValue(
+  result.value, undefined, 'Result `value` is undefined when complete'
+);
+assert.sameValue(
+  result.done, true, 'Result `done` flag is `true` when complete'
+);

test/built-ins/GeneratorPrototype/return/try-finally-nested-try-catch-within-outer-try-before-nested.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: 25.3.1.3
+description: >
+    When a generator is paused within a `try` block of a `try..catch` statement
+    and before a nested `try..catch` statement, `return` should interrupt
+    control flow as if a `return` statement had appeared at that location in
+    the function body.
+---*/
+
+var inTry = false;
+var inFinally = false;
+function* g() {
+  try {
+    inTry = true;
+    yield;
+    try {
+      $ERROR('This code is unreachable (within nested `try` block)');
+    } catch (e) {
+      throw e;
+    }
+    $ERROR('This code is unreacahable (following nested `try` statement)');
+  } finally {
+    inFinally = true;
+  }
+  $ERROR('This codeis unreachable (following outer `try` statement)');
+}
+var iter = g();
+var result;
+
+iter.next();
+
+assert.sameValue(inTry, true, '`try` code path executed');
+assert.sameValue(inFinally, false, '`finally` code path not executed');
+
+result = iter.return(45);
+assert.sameValue(result.value, 45, 'Second result `value`');
+assert.sameValue(result.done, true, 'Second result `done` flag');
+assert.sameValue(inFinally, true, '`finally` code path executed');
+
+result = iter.next();
+assert.sameValue(
+  result.value, undefined, 'Result `value` is undefined when complete'
+);
+assert.sameValue(
+  result.done, true, 'Result `done` flag is `true` when complete'
+);

test/built-ins/GeneratorPrototype/return/try-finally-within-finally.js

@@ -0,0 +1,38 @@
+// Copyright (C) 2015 the V8 project authors. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+/*---
+es6id: 25.3.1.3
+description: >
+    When a generator is paused within the `finally` block of a `try..finally`
+    statement, `return` should interrupt control flow as if a `return`
+    statement had appeared at that location in the function body.
+---*/
+
+var inFinally = true;
+function* g() {
+  try {
+  } finally {
+    inFinally = true;
+    yield;
+    $ERROR('This code is unreachable (within `finally` block)');
+  }
+  $ERROR('This code is unreachable (following `try` statement)');
+}
+var iter = g();
+var result;
+
+iter.next();
+
+assert.sameValue(inFinally, true, '`finally` code path executed');
+
+result = iter.return(45);
+assert.sameValue(result.value, 45, 'Result `value` following `return`');
+assert.sameValue(result.done, true, 'Result `done` flag following `return`');
+
+result = iter.next();
+assert.sameValue(
+  result.value, undefined, 'Result `value` is undefined when complete'
+);
+assert.sameValue(
+  result.done, true, 'Result `done` flag is `true` when complete'
+);

test/built-ins/GeneratorPrototype/return/try-finally-within-try.js

@@ -0,0 +1,42 @@
+// Copyright (C) 2015 the V8 project authors. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+/*---
+es6id: 25.3.1.3
+description: >
+    When a generator is paused within a `try` block of a `try..finally`
+    statement, `return` should interrupt control flow as if a `return`
+    statement had appeared at that location in the function body.
+---*/
+
+var inTry = false;
+var inFinally = false;
+function* g() {
+  try {
+    inTry = true;
+    yield;
+    $ERROR('This code is unreachable (within `try` block)');
+  } finally {
+    inFinally = true;
+  }
+  $ERROR('This code is unreachable (following `try` statement)');
+}
+var iter = g();
+var result;
+
+iter.next();
+
+assert.sameValue(inTry, true, '`try` block code path executed');
+assert.sameValue(inFinally, false, '`finally` code path not executed');
+
+result = iter.return(45);
+assert.sameValue(result.value, 45, 'Result `value` following `return`');
+assert.sameValue(result.done, true, 'Result `done` flag following `return`');
+assert.sameValue(inFinally, true, '`finally` code path executed');
+
+result = iter.next();
+assert.sameValue(
+  result.value, undefined, 'Result `value` is undefined when complete'
+);
+assert.sameValue(
+  result.done, true, 'Result `done` flag is `true` when complete'
+);

test/built-ins/GeneratorPrototype/throw/try-catch-following-catch.js

@@ -19,9 +19,8 @@ function* g() {
   }
   yield 3;
 }
-var iter, result, exception;
+var iter, result;
 
-exception = new Test262Error();
 iter = g();
 result = iter.next();
 assert.sameValue(result.value, 1, 'First result `value`');