JSX Syntax Highlighting - Nullish Coalescing Operator breaks highlighting

[zvodd]

🐛 bug report

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Description of the problem

JSX syntax highlighting is broken following the use of the the Nullish Coalescing Operator (??).

How has this issue affected you? What are you trying to accomplish?

To Reproduce

Use the Nullish Coalescing Operator in an arrow function in a JSX file. Code following will have broken syntax highlighting.

See https://github.com/zvodd/ReactDemo-EditableTexts/tree/main/ for repo, or...

Link to sandbox: https://codesandbox.io/s/agitated-shockley-9oxb0?file=/src/App.js

Your Environment

Software	Name/Version
Сodesandbox	?? / Live [15-Mar-2021]
Browser	Chrome 89.0.4389.82
Operating System	Windows 10 AMD64

[CompuIves]

This is probably related to our TS extension, we should update the .tmLanguage of TypeScript to support the new syntax highlighting. https://github.com/codesandbox/codesandbox-client/blob/master/standalone-packages/vscode-extensions/out/extensions/typescript-basics/syntaxes/TypeScript.tmLanguage.json#L1

[stevenhao]

The repro link in the original post is formatted a bit strangely (points to this issue instead); here's a clickable link https://codesandbox.io/s/agitated-shockley-9oxb0?file=/src/App.js

[stevenhao]

The current tmlanguage version used by codesandbox-client was generated off of this commit from July 29, 2019 (microsoft/TypeScript-TmLanguage@84238ef)

Nullish coalescing was added to microsoft/TypeScript-TmLanguage in August 22, 2019 microsoft/TypeScript-TmLanguage#768 and seems to be a pretty small diff (screenshot)

I attempted to follow instructions in the readme in https://github.com/codesandbox/codesandbox-client/tree/master/standalone-packages/vscode-extensions/out/extensions/typescript-basics/syntaxes but it seems to be a bit out of date

• It references npm run update-grammars but the scripts field of package.json spells it update-grammar
• The update-grammar script fails because it references a nonexistent file update-grammars.js (see error below)

Error: Cannot find module '/Users/stevenhao/codesandbox-client/standalone-packages/vscode-extensions/out/extensions/typescript-basics/build/update-grammars.js'

[stevenhao]

Here's a fix: #6205