// Copyright (C) 2019 Leo Balter. All rights reserved. // This code is governed by the BSD license found in the LICENSE file. /*--- description: > Short circuit if the CoalesceExpressionHead is not undefined or null (string) esid: sec-conditional-operator info: | ConditionalExpression : ShortCircuitExpression ShortCircuitExpression ? AssignmentExpression : AssignmentExpression ShortCircuitExpression : LogicalORExpression CoalesceExpression CoalesceExpression : CoalesceExpressionHead ?? BitwiseORExpression CoalesceExpressionHead : CoalesceExpression BitwiseORExpression Runtime Semantics: Evaluation CoalesceExpression:CoalesceExpressionHead??BitwiseORExpression 1. Let lref be the result of evaluating CoalesceExpressionHead. 2. Let lval be ? GetValue(lref). 3. If lval is undefined or null, a. Let rref be the result of evaluating BitwiseORExpression. b. Return ? GetValue(rref). 4. Otherwise, return lval. features: [coalesce-expression] ---*/ var x; var str = 'undefined'; x = undefined; x = str ?? 1; assert.sameValue(x, str, 'str ?? 1'); x = undefined; x = str ?? null; assert.sameValue(x, str, 'str ?? null'); x = undefined; x = str ?? undefined; assert.sameValue(x, str, 'str ?? undefined'); x = undefined; x = str ?? null ?? undefined; assert.sameValue(x, str, 'str ?? null ?? undefined'); x = undefined; x = str ?? undefined ?? null; assert.sameValue(x, str, 'str ?? undefined ?? null'); x = undefined; x = str ?? null ?? null; assert.sameValue(x, str, 'str ?? null ?? null'); x = undefined; x = str ?? undefined ?? undefined; assert.sameValue(x, str, 'str ?? null ?? null'); x = undefined; x = null ?? str ?? null; assert.sameValue(x, str, 'null ?? str ?? null'); x = undefined; x = null ?? str ?? undefined; assert.sameValue(x, str, 'null ?? str ?? undefined'); x = undefined; x = undefined ?? str ?? null; assert.sameValue(x, str, 'undefined ?? str ?? null'); x = undefined; x = undefined ?? str ?? undefined; assert.sameValue(x, str, 'undefined ?? str ?? undefined'); reportCompare(0, 0);