// This file was procedurally generated from the following sources: // - src/dstr-binding/ary-ptrn-elem-id-init-skipped.case // - src/dstr-binding/default/for-of-const.template /*--- description: Destructuring initializer is not evaluated when value is not `undefined` (for-of statement) esid: sec-for-in-and-for-of-statements-runtime-semantics-labelledevaluation es6id: 13.7.5.11 features: [destructuring-binding] flags: [generated] info: | IterationStatement : for ( ForDeclaration of AssignmentExpression ) Statement [...] 3. Return ForIn/OfBodyEvaluation(ForDeclaration, Statement, keyResult, lexicalBinding, labelSet). 13.7.5.13 Runtime Semantics: ForIn/OfBodyEvaluation [...] 3. Let destructuring be IsDestructuring of lhs. [...] 5. Repeat [...] h. If destructuring is false, then [...] i. 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 SingleNameBinding : BindingIdentifier Initializeropt [...] 6. If Initializer is present and v is undefined, then [...] 7. If environment is undefined, return PutValue(lhs, v). 8. Return InitializeReferencedBinding(lhs, v). ---*/ var initCount = 0; function counter() { initCount += 1; } var iterCount = 0; for (const [w = counter(), x = counter(), y = counter(), z = counter()] of [[null, 0, false, '']]) { assert.sameValue(w, null); assert.sameValue(x, 0); assert.sameValue(y, false); assert.sameValue(z, ''); assert.sameValue(initCount, 0); iterCount += 1; } assert.sameValue(iterCount, 1, 'iteration occurred as expected');