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// Copyright (C) 2016 the V8 project authors. All rights reserved.
// This code is governed by the BSD license found in the LICENSE file.
/*---
es6id: 13.12.11
description: >
Completion value when execution continues through multiple cases and ends
with a normal completion
info: |
SwitchStatement : switch ( Expression ) CaseBlock
[...]
8. Let R be the result of performing CaseBlockEvaluation of CaseBlock with
argument switchValue.
9. Set the running execution context’s LexicalEnvironment to oldEnv.
10. Return R.
13.12.9 Runtime Semantics: CaseBlockEvaluation
CaseBlock : { CaseClausesopt DefaultClause CaseClausesopt }
1. Let V = undefined.
2. Let A be the list of CaseClause items in the first CaseClauses, in
source text order. If the first CaseClauses is not present A is « ».
3. Let found be false.
4. Repeat for each CaseClause C in A
[...]
5. Let foundInB be false.
6. Let B be the List containing the CaseClause items in the second
CaseClauses, in source text order. If the second CaseClauses is not
present B is « ».
7. If found is false, then
a. Repeat for each CaseClause C in B
i. If foundInB is false, then
1. Let clauseSelector be the result of CaseSelectorEvaluation of
C.
2. If clauseSelector is an abrupt completion, then
a. If clauseSelector.[[value]] is empty, return
Completion{[[type]]: clauseSelector.[[type]], [[value]]:
undefined, [[target]]: clauseSelector.[[target]]}.
b. Else, return Completion(clauseSelector).
3. Let foundInB be the result of performing Strict Equality
Comparison input === clauseSelector.[[value]].
ii. If foundInB is true, then
1. Let R be the result of evaluating CaseClause C.
2. If R.[[value]] is not empty, let V = R.[[value]].
3. If R is an abrupt completion, return
Completion(UpdateEmpty(R, V)).
8. If foundInB is true, return NormalCompletion(V).
---*/
assert.sameValue(
eval('1; switch ("a") { default: case "a": 2; case "b": 3; }'),
3,
'Non-empty value replaces previous non-empty value'
);
assert.sameValue(
eval('4; switch ("a") { default: case "a": case "b": 5; }'),
5,
'Non-empty value replaces empty value'
);
assert.sameValue(
eval('6; switch ("a") { default: case "a": 7; case "b": }'),
7,
'Empty value does not replace previous non-empty value'
);
reportCompare(0, 0);
|
