Git - fix git diff raw parsing to correctly handle renamed files

[lszomoru]

Related #286776

[Copilot]

Pull request overview

This PR fixes a bug in the git extension's parsing of git diff raw output to correctly handle renamed files. The issue occurs when parsing --numstat output with the -z flag, where renamed files have an empty filePath followed by null-terminated old and new paths.

Changes:

• Modified the parseGitChangesRaw function to detect when filePath is empty in --numstat output
• Added logic to skip the old path and use the new path for mapping numstat data to renamed files

[Copilot]

The code should validate that renamePath exists before using it. If segments[index] is undefined (e.g., due to malformed git output), this will cause path.isAbsolute(renamePath) to throw an error or create an invalid path. Consider adding a check similar to the one used for renamed files in the --raw parsing section (lines 1123-1129).

Suggested change

	// old path and use the new path for the stats key.
	index++;
	const renamePath = segments[index++];
	// old path and use the new path for the stats key.
	if (index >= segments.length) {
	break;
	}
	index++;
	if (index >= segments.length) {
	break;
	}
	const renamePath = segments[index++];
	if (!renamePath) {
	break;
	}