| // This file was procedurally generated from the following sources: |
| // - src/dstr-binding-for-await/ary-ptrn-rest-id-elision.case |
| // - src/dstr-binding-for-await/default/for-await-of-async-func-const-async.template |
| /*--- |
| description: Rest element following elision elements (for-await-of statement) |
| esid: sec-for-in-and-for-of-statements-runtime-semantics-labelledevaluation |
| features: [destructuring-binding, async-iteration] |
| flags: [generated, async] |
| info: | |
| IterationStatement : |
| for await ( ForDeclaration of AssignmentExpression ) Statement |
| |
| [...] |
| 2. Return ? ForIn/OfBodyEvaluation(ForDeclaration, Statement, keyResult, |
| lexicalBinding, labelSet, async). |
| |
| 13.7.5.13 Runtime Semantics: ForIn/OfBodyEvaluation |
| |
| [...] |
| 4. Let destructuring be IsDestructuring of lhs. |
| [...] |
| 6. Repeat |
| [...] |
| j. If destructuring is false, then |
| [...] |
| k. Else |
| i. If lhsKind is assignment, then |
| [...] |
| ii. Else if lhsKind is varBinding, then |
| [...] |
| iii. Else, |
| 1. Assert: lhsKind is lexicalBinding. |
| 2. Assert: lhs is a ForDeclaration. |
| 3. Let status be the result of performing BindingInitialization |
| for lhs passing nextValue and iterationEnv as arguments. |
| [...] |
| |
| 13.3.3.6 Runtime Semantics: IteratorBindingInitialization |
| ArrayBindingPattern : [ Elisionopt BindingRestElement ] |
| 1. If Elision is present, then |
| a. Let status be the result of performing |
| IteratorDestructuringAssignmentEvaluation of Elision with |
| iteratorRecord as the argument. |
| b. ReturnIfAbrupt(status). |
| 2. Return the result of performing IteratorBindingInitialization for |
| BindingRestElement with iteratorRecord and environment as arguments. |
| ---*/ |
| var values = [1, 2, 3, 4, 5]; |
| |
| var iterCount = 0; |
| var asyncIter = (async function*() { |
| yield* [values]; |
| })(); |
| |
| async function fn() { |
| for await (const [ , , ...x] of asyncIter) { |
| assert(Array.isArray(x)); |
| assert.sameValue(x.length, 3); |
| assert.sameValue(x[0], 3); |
| assert.sameValue(x[1], 4); |
| assert.sameValue(x[2], 5); |
| assert.notSameValue(x, values); |
| |
| iterCount += 1; |
| } |
| } |
| |
| fn() |
| .then(() => assert.sameValue(iterCount, 1, 'iteration occurred as expected'), $DONE) |
| .then($DONE, $DONE); |