Function getGitDiffSize

src/utils/commitAttribution.ts:752–789

(filePath: string)

 * For deleted files, returns the size of the deleted content.
 */
export async function getGitDiffSize(filePath: string): Promise<number> {
  const cwd = getAttributionRepoRoot()

  try {
    // Use git diff --stat to get a summary of changes
    const result = await execFileNoThrowWithCwd(
      gitExe(),
      ['diff', '--cached', '--stat', '--', filePath],
      { cwd, timeout: 5000 },
    )

    if (result.code !== 0 || !result.stdout) {
      return 0
    }

    // Parse the stat output to extract additions and deletions
    // Format: " file | 5 ++---" or " file | 10 +"
    const lines = result.stdout.split('\n').filter(Boolean)
    let totalChanges = 0

    for (const line of lines) {
      // Skip the summary line (e.g., "1 file changed, 3 insertions(+), 2 deletions(-)")
      if (line.includes('file changed') || line.includes('files changed')) {
        const insertMatch = line.match(/(\d+) insertions?/)
        const deleteMatch = line.match(/(\d+) deletions?/)

        // Use line-based changes and approximate chars per line (~40 chars average)
        const insertions = insertMatch ? parseInt(insertMatch[1]!, 10) : 0
        const deletions = deleteMatch ? parseInt(deleteMatch[1]!, 10) : 0
        totalChanges += (insertions + deletions) * 40
      }
    }

    return totalChanges
  } catch {
    return 0
  }
}

/**
 * Check if a file was deleted in the staged changes.