[0/5] `--whitespace=fix` with `--no-ignore-whitespace`

Message

Rubén Justo Aug. 25, 2024, 10:09 a.m. UTC

When we see `--whitespace=fix` we don't consider a possible option:
`--no-ignore-whitespace`.  The following example produces unexpected,
at least for me, results:

    $ printf "a \nb\nc\n" >file
    $ git add file
    $ cat >patch <<END
    --- a/file
    +++ b/file
    @@ -1,3 +1,2 @@
     a
    -b
     c
    END
    $ git apply --no-ignore-whitespace --whitespace=fix patch
    $ xxd file
    00000000: 610a 630a                                a.c.

`git apply` should fail because the context line with 'a' doesn't
match the line with 'a ' in the file.

This series aims to make `--whitespace=fix` strictly match context
lines even if they have whitespace errors.

Adding a new `ignore_ws_default` is intended to reduce the blast
radius of changing the behavior of `--whitespace=fix`.  Perhaps there
are better ways to do this.  I'm open to suggestions.

The last two patches [4-5/5] contain minor code improvements I made
while reading the code working on this series.  They can be discarded
if anyone has concerns.

Thanks.

Rubén Justo (4):
  apply: introduce `ignore_ws_default`
  apply: honor `ignore_ws_none` with `correct_ws_error`
  apply: whitespace errors in context lines if we have `ignore_ws_none`
  apply: error message in `record_ws_error()`
  t4124: move test preparation into the test context

 apply.c                  | 17 ++++++++--------
 apply.h                  |  1 +
 t/t4124-apply-ws-rule.sh | 44 +++++++++++++++++++++++++++-------------
 3 files changed, 40 insertions(+), 22 deletions(-)