Function getCommitDiff

app/src/lib/git/diff.ts:115–148

(
  repository: Repository,
  file: FileChange,
  commitish: string,
  hideWhitespaceInDiff: boolean = false
)

 *                  to a commit.
 */
export async function getCommitDiff(
  repository: Repository,
  file: FileChange,
  commitish: string,
  hideWhitespaceInDiff: boolean = false
): Promise<IDiff> {
  const args = [
    'log',
    commitish,
    ...(hideWhitespaceInDiff ? ['-w'] : []),
    '-m',
    '-1',
    '--first-parent',
    '--patch-with-raw',
    '--format=',
    '-z',
    '--no-color',
    '--',
    ensureRelativePath(file.path),
  ]

  if (
    file.status.kind === AppFileStatusKind.Renamed ||
    file.status.kind === AppFileStatusKind.Copied
  ) {
    args.push(ensureRelativePath(file.status.oldPath))
  }

  const { stdout } = await git(args, repository.path, 'getCommitDiff', {
    encoding: 'buffer',
  })

  return buildDiff(stdout, repository, file, commitish, commitish)
}

/**
 * Render the diff between two branches with --merge-base for a file