Function write_paths_patch 

pub fn write_paths_patch<W: Write>(
    a: &Path,
    b: &Path,
    opts: &DiffOptions,
    out: &mut W,
) -> Result<bool, NoIndexError>

Write git diff --no-index --binary-style patch bytes for two filesystem paths.

Returns Ok(true) when the paths differ.

Errors

Propagates NoIndexError and repository/patch I/O failures.