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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 only the final case matches
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 : { CaseClauses }
1. Let V = undefined.
2. Let A be the List of CaseClause items in CaseClauses, in source text
order.
3. Let found be false.
4. Repeat for each CaseClause C in A,
a. If found is false, then
i. Let clauseSelector be the result of CaseSelectorEvaluation of C.
ii. If clauseSelector is an abrupt completion, then
1. If clauseSelector.[[value]] is empty, return
Completion{[[type]]: clauseSelector.[[type]], [[value]]:
undefined, [[target]]: clauseSelector.[[target]]}.
2. Else, return Completion(clauseSelector).
iii. Let found be the result of performing Strict Equality Comparison
input === clauseSelector.[[value]].
b. If found is true, then
i. Let R be the result of evaluating C.
ii. If R.[[value]] is not empty, let V = R.[[value]].
iii. If R is an abrupt completion, return Completion(UpdateEmpty(R,
V)).
5. Return NormalCompletion(V).
---*/
assert.sameValue(
eval('1; switch ("a") { case "a": }'),
undefined,
'empty StatementList (lone case)'
);
assert.sameValue(
eval('2; switch ("a") { case "a": 3; }'),
3,
'non-empy StatementList (lone case)'
);
assert.sameValue(
eval('4; switch ("b") { case "a": case "b": }'),
undefined,
'empty StatementList (following an empty case)'
);
assert.sameValue(
eval('5; switch ("b") { case "a": case "b": 6; }'),
6,
'non-empty StatementList (following an empty case)'
);
assert.sameValue(
eval('7; switch ("b") { case "a": 8; case "b": }'),
undefined,
'empty StatementList (following a non-empty case)'
);
assert.sameValue(
eval('9; switch ("b") { case "a": 10; case "b": 11; }'),
11,
'non-empty StatementList (following a non-empty case)'
);
|
