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Diffstat (limited to 'js/src/tests/test262/language/expressions/coalesce/short-circuit-prevents-evaluation.js')
-rw-r--r-- | js/src/tests/test262/language/expressions/coalesce/short-circuit-prevents-evaluation.js | 58 |
1 files changed, 58 insertions, 0 deletions
diff --git a/js/src/tests/test262/language/expressions/coalesce/short-circuit-prevents-evaluation.js b/js/src/tests/test262/language/expressions/coalesce/short-circuit-prevents-evaluation.js new file mode 100644 index 000000000..14cbd109e --- /dev/null +++ b/js/src/tests/test262/language/expressions/coalesce/short-circuit-prevents-evaluation.js @@ -0,0 +1,58 @@ +// Copyright (C) 2019 Leo Balter. All rights reserved. +// This code is governed by the BSD license found in the LICENSE file. + +/*--- +description: > + Short circuit can prevent evaluation of the right-side expressions +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; +function poison() { + throw new Test262Error('should not evaluate poison'); +} + +x = undefined; +x = undefined ?? 42 ?? undefined ?? poison(); +assert.sameValue(x, 42); + +x = undefined; +x = 42 ?? undefined ?? poison(); +assert.sameValue(x, 42); + +x = undefined; +x = undefined ?? 42 ?? poison(); +assert.sameValue(x, 42); + +x = undefined; +x = 42 ?? poison(); +assert.sameValue(x, 42); + +reportCompare(0, 0); |