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`typeof` with `<` breaks syntax highlighting

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Assessment

Difficulty
3/5
Estimated time
1-2 days
Newbie friendliness
45/100
Issue type
Bug
Clarity
Clearly specified
Activity status
Stale
Domain
tooling

Research direction

Reproduce the issue with the two TypeScript and JavaScript snippets in the report, beginning with the repository's TextMate grammar. Verify that < and <= after typeof remain highlighted as relational operators and that highlighting continues through the rest of each snippet.

Written by the indexing model from the issue text.

Description

JavaScript and TypeScript Nightly version: v5.1.20230416

Code

typeof x < ''; function f() {}

For context, here's the whole code where I noticed it (common in minified js):

var gt = typeof globalThis < "u" ? globalThis : typeof window < "u" ? window : typeof global < "u" ? global : typeof self < "u" ? self : {};

Actual behaviour: typeof with < or <= gets interpreted as the begin of a type parameter and breaks all syntax highlighting after it.
image
image

Expected behaviour: should be a relational operator.
image

Dominant language
TypeScript
Stars
471
Forks
149
PR merge metrics
No merged PRs in 30d

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