[PATCH v3 0/2] stash: fix and improve "git stash -p <pathspec>"

From: Phillip Wood <phillip.wood@dunelm.org.uk>

"git stash -p <pathspec>" should imply "git stash push -p <pathspec>" but that was broken by a code cleanup in c3713cede7 (stash: eliminate crude option parsing, 2020-02-17). This regression is fixed in the first patch. Although "-p" implies the "push" subcommand "--patch" has never implied "push". That is fixed in the second patch.

Thanks to Martin for his comments on V2

Changes since V2:
 - Made test stricter as suggested by Martin

Thanks to Junio for his comments on V1.

Changes since V1:
 - Split out the regression fix into its own patch

Base-Commit: 1a8a4971cc6c179c4dd711f4a7f5d7178f4b3ab7
Published-As: https://github.com/phillipwood/git/releases/tag/pw%2Fstash-assume-push-with-dash-p%2Fv3
View-Changes-At: https://github.com/phillipwood/git/compare/1a8a4971c...d3a958430
Fetch-It-Via: git fetch https://github.com/phillipwood/git pw/stash-assume-push-with-dash-p/v3

Phillip Wood (2):
  stash: allow "git stash -p <pathspec>" to assume push again
  stash: allow "git stash [<options>] --patch <pathspec>" to assume push

 builtin/stash.c  | 10 +++++++---
 t/t3903-stash.sh | 22 ++++++++++++++++++++++
 2 files changed, 29 insertions(+), 3 deletions(-)

Range-diff against v2:
1:  2cd67f5cd85 ! 1:  c147eaf2eae stash: allow "git stash -p <pathspec>" to assume push again
    @@ Commit message
         Fix this by regression by checking argv[1] instead of argv[0] and add a
         couple of tests to prevent future regressions.
     
    +    Helped-by: Martin Ågren <martin.agren@gmail.com>
         Signed-off-by: Phillip Wood <phillip.wood@dunelm.org.uk>
     
      ## builtin/stash.c ##
    @@ t/t3903-stash.sh: test_expect_success 'stash -- <pathspec> stashes and restores
      '
      
     +test_expect_success 'stash -p <pathspec> stash and restores the file' '
    -+	cat file >expect-file &&
    -+	echo changed-file >file &&
    ++	test_write_lines b c >file &&
    ++	git commit -m "add a few lines" file &&
    ++	test_write_lines a b c d >file &&
    ++	test_write_lines b c d >expect-file &&
     +	echo changed-other-file >other-file &&
    -+	echo a | git stash -p file &&
    ++	test_write_lines s y n | git stash -p file &&
     +	test_cmp expect-file file &&
     +	echo changed-other-file >expect &&
     +	test_cmp expect other-file &&
    ++	git checkout HEAD -- file &&
     +	git stash pop &&
     +	test_cmp expect other-file &&
    -+	echo changed-file >expect &&
    ++	test_write_lines a b c >expect &&
     +	test_cmp expect file
     +'
     +
2:  98ad3de9770 ! 2:  d3a95843055 stash: allow "git stash [<options>] --patch <pathspec>" to assume push
    @@ t/t3903-stash.sh: test_expect_success 'stash -- <pathspec> stashes and restores
      
     -test_expect_success 'stash -p <pathspec> stash and restores the file' '
     +test_expect_success 'stash --patch <pathspec> stash and restores the file' '
    - 	cat file >expect-file &&
    - 	echo changed-file >file &&
    + 	test_write_lines b c >file &&
    + 	git commit -m "add a few lines" file &&
    + 	test_write_lines a b c d >file &&
    + 	test_write_lines b c d >expect-file &&
      	echo changed-other-file >other-file &&
    --	echo a | git stash -p file &&
    -+	echo a | git stash -m "stash bar" --patch file &&
    +-	test_write_lines s y n | git stash -p file &&
    ++	test_write_lines s y n | git stash -m "stash bar" --patch file &&
      	test_cmp expect-file file &&
      	echo changed-other-file >expect &&
      	test_cmp expect other-file &&