jquery / jquery/esprima

'yield' parsed as keyword instead of identifier

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Dominant language
TypeScript
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Description

In the file src/scanner.ts, in the function isKeyword, yield is treated as a keyword, which is incorrect. This should be handled by the function nextToken() in src/parser.ts, where there already exists an appropriate test for strictness and reserved words in strict mode.

Steps to reproduce
esprima.parseScript('yield : 1')
Expected output

Valid syntax tree.

Actual output

Error: Line 1: Unexpected token :

Relevant references

https://www.ecma-international.org/ecma-262/8.0/index.html#sec-strict-mode-of-ecmascript states that yield is a keyword only in strict mode.

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Research direction

Start in src/scanner.ts at isKeyword and then read nextToken() in src/parser.ts, including the existing strictness and reserved-words test. Reproduce the issue with esprima.parseScript('yield : 1') and verify that it produces a valid syntax tree while strict-mode handling remains correct.

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Assessment

Tech stack
javascript, typescript
Domain
compilers
Issue type
Bug
Difficulty
2/5
Estimated time
1-3 hours
Activity status
Stale
Clarity
Clearly specified
Newbie friendliness
45/100

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