// 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-generator-function-definitions-runtime-semantics-evaluation es6id: 14.4.14 description: > "Return" completion returned when `return` method is not defined info: | YieldExpression : yield * AssignmentExpression 1. Let exprRef be the result of evaluating AssignmentExpression. 2. Let value be ? GetValue(exprRef). 3. Let iterator be ? GetIterator(value). 4. Let received be NormalCompletion(undefined). 5. Repeat a. If received.[[Type]] is normal, then [...] b. Else if received.[[Type]] is throw, then [...] c. Else, i. Assert: received.[[Type]] is return. ii. Let return be ? GetMethod(iterator, "return"). iii. If return is undefined, return Completion(received). features: [generators, Symbol.iterator] ---*/ var badIter = {}; var throwCount = 0; var returnCount = 0; var hitNextStatement = false; var hitCatch = false; var hitFinally = false; var spyResult = { next: function() { return { done: false }; } }; Object.defineProperty(spyResult, 'throw', { get: function() { throwCount += 1; } }); Object.defineProperty(spyResult, 'return', { get: function() { returnCount += 1; } }); badIter[Symbol.iterator] = function() { return spyResult; }; function* g() { try { yield * badIter; hitNextStatement = true; } catch (_) { hitCatch = true; } finally { hitFinally = true; } } var iter = g(); iter.next(); iter.return(); assert.sameValue(throwCount, 0, '`throw` property access'); assert.sameValue(returnCount, 1, '`return` property access'); assert.sameValue( hitFinally, true, 'Generator execution was resumed' ); assert.sameValue( hitNextStatement, false, 'Abrupt completion interrupted control flow' ); assert.sameValue( hitCatch, false, 'Abrupt completion not interpreted as "throw"' ); reportCompare(0, 0);