cptn-a-fall-thru-nrml.js (2445B)
1 // Copyright (C) 2016 the V8 project authors. All rights reserved. 2 // This code is governed by the BSD license found in the LICENSE file. 3 /*--- 4 es6id: 13.12.11 5 description: > 6 Completion value when execution continues through multiple cases and ends 7 with a normal completion 8 info: | 9 SwitchStatement : switch ( Expression ) CaseBlock 10 11 [...] 12 8. Let R be the result of performing CaseBlockEvaluation of CaseBlock with 13 argument switchValue. 14 9. Set the running execution context’s LexicalEnvironment to oldEnv. 15 10. Return R. 16 17 13.12.9 Runtime Semantics: CaseBlockEvaluation 18 19 CaseBlock : { CaseClausesopt DefaultClause CaseClausesopt } 20 21 1. Let V = undefined. 22 2. Let A be the list of CaseClause items in the first CaseClauses, in 23 source text order. If the first CaseClauses is not present A is « ». 24 3. Let found be false. 25 4. Repeat for each CaseClause C in A 26 a. If found is false, then 27 i. Let clauseSelector be the result of CaseSelectorEvaluation of C. 28 ii. If clauseSelector is an abrupt completion, then 29 [...] 30 iii. Let found be the result of performing Strict Equality Comparison 31 input === clauseSelector.[[value]]. 32 b. If found is true, then 33 i. Let R be the result of evaluating C. 34 ii. If R.[[value]] is not empty, let V = R.[[value]]. 35 [...] 36 5. Let foundInB be false. 37 6. Let B be the List containing the CaseClause items in the second 38 CaseClauses, in source text order. If the second CaseClauses is not 39 present B is « ». 40 7. If found is false, then 41 [...] 42 [...] 43 9. Let R be the result of evaluating DefaultClause. 44 10. If R.[[value]] is not empty, let V = R.[[value]]. 45 11. If R is an abrupt completion, return Completion(UpdateEmpty(R, V)). 46 12. Repeat for each CaseClause C in B (NOTE this is another complete 47 iteration of the second CaseClauses) 48 [...] 49 13. Return NormalCompletion(V). 50 ---*/ 51 52 assert.sameValue( 53 eval('1; switch ("a") { case "a": 2; default: 3; }'), 54 3, 55 'Non-empty value replaces previous non-empty value' 56 ); 57 assert.sameValue( 58 eval('4; switch ("a") { case "a": default: 5; }'), 59 5, 60 'Non-empty value replaces empty value' 61 ); 62 assert.sameValue( 63 eval('6; switch ("a") { case "a": 7; default: }'), 64 7, 65 'Empty value does not replace previous non-empty value' 66 ); 67 68 reportCompare(0, 0);