array-elem-nested-obj-yield-expr.js (1708B)
1 // This file was procedurally generated from the following sources: 2 // - src/dstr-assignment/array-elem-nested-obj-yield-expr.case 3 // - src/dstr-assignment/default/for-of.template 4 /*--- 5 description: When a `yield` token appears within the Initializer of a nested destructuring assignment and within a generator function body, it behaves as a YieldExpression. (For..of statement) 6 esid: sec-for-in-and-for-of-statements-runtime-semantics-labelledevaluation 7 features: [generators, destructuring-binding] 8 flags: [generated] 9 info: | 10 IterationStatement : 11 for ( LeftHandSideExpression of AssignmentExpression ) Statement 12 13 1. Let keyResult be the result of performing ? ForIn/OfHeadEvaluation(« », 14 AssignmentExpression, iterate). 15 2. Return ? ForIn/OfBodyEvaluation(LeftHandSideExpression, Statement, 16 keyResult, assignment, labelSet). 17 18 13.7.5.13 Runtime Semantics: ForIn/OfBodyEvaluation 19 20 [...] 21 4. If destructuring is true and if lhsKind is assignment, then 22 a. Assert: lhs is a LeftHandSideExpression. 23 b. Let assignmentPattern be the parse of the source text corresponding to 24 lhs using AssignmentPattern as the goal symbol. 25 [...] 26 ---*/ 27 var iterationResult, iter, x; 28 29 iter = (function*() { 30 31 var counter = 0; 32 33 for ([{ x = yield }] of [[{}]]) { 34 35 counter += 1; 36 } 37 38 assert.sameValue(counter, 1); 39 40 }()); 41 42 iterationResult = iter.next(); 43 44 assert.sameValue(iterationResult.value, undefined); 45 assert.sameValue(iterationResult.done, false); 46 assert.sameValue(x, undefined); 47 48 iterationResult = iter.next(4); 49 50 assert.sameValue(iterationResult.value, undefined); 51 assert.sameValue(iterationResult.done, true); 52 assert.sameValue(x, 4); 53 54 reportCompare(0, 0);