Add diff chunk header lines to Git

Search Terms

userdiff xfuncname

Suggestion

Please add regular expressions to https://github.com/git/git/blob/master/userdiff.c such that TypeScript constructs can be identified in a predictable manner by the Git diff algorithm.

Use Cases

When I do a git diff or git add -p that includes TypeScript code, it's nice to see the function and/or class names of the changed lines I am looking at.

Examples

• git diff -- *.ts
• git add -p -- *.ts

Checklist

My suggestion meets these guidelines:

• This wouldn't be a breaking change in existing TypeScript/JavaScript code
• This wouldn't change the runtime behavior of existing JavaScript code
• This could be implemented without emitting different JS based on the types of the expressions
• This isn't a runtime feature (e.g. library functionality, non-ECMAScript syntax with JavaScript output, etc.)
• This feature would agree with the rest of TypeScript's Design Goals.
  • Particularly "Provide a structuring mechanism for larger pieces of code."

Start by reviewing Git's userdiff.c, which the issue identifies as the implementation entry point, and inspect how existing language patterns expose function or class names in diff headers. Add TypeScript patterns for .ts files, then verify that git diff and git add -p show the relevant construct names for the examples in the issue.