Non-identifier tokens are valid part/start of identifier when specified with \u
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- Dominant language
- TypeScript
- Stars
- 7.1k
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Description
Test case
\u{1}
Expected: An "Unexpected token" exception.
Actual: A valid AST is generated.
Any escaped character is treated as part/start of an identifier (independently of its code):
\u{20} // This whitespace is valid identifier.
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Research direction
Reproduce the JavaScript snippets with Esprima and trace the parser entry point that handles escaped identifier characters. Confirm that \u{1} and \u{20} are rejected as invalid identifier characters, with the first case producing an "Unexpected token" exception.
Written by the indexing model from the issue text.
Assessment
- Tech stack
- javascript, typescript
- Domain
- compilers
- Issue type
- Bug
- Difficulty
- 3/5
- Estimated time
- 1-2 days
- Activity status
- Stale
- Clarity
- Clearly specified
- Newbie friendliness
- 45/100