From: Tilman Vogel Date: Thu, 27 Aug 2020 09:05:26 GMT Subject: Re: [PATCH] patch-id: ignore newline at end of file in diff_flush_patch_id() Message-ID: In-Reply-To: That's great, thanks René! Looking forward to try that out! Tilman Am Mi., 19. Aug. 2020 um 00:09 Uhr schrieb René Scharfe : > > Whitespace is ignored when calculating patch IDs. This is done by > removing all whitespace from diff lines before hashing them, including > a newline at the end of a file. If that newline is missing, however, > diff reports that fact in a separate line containing "\ No newline at > end of file\n", and this marker is hashed like a context line. > > This goes against our goal of making patch IDs independent of > whitespace. Use the same heuristic that 2485eab55cc (git-patch-id: do > not trip over "no newline" markers, 2011-02-17) added to git patch-id > instead and skip diff lines that start with a backslash and a space > and are longer than twelve characters. > > Reported-by: Tilman Vogel > Initial-test-by: Tilman Vogel > Signed-off-by: René Scharfe > --- > diff.c | 2 ++ > t/t3500-cherry.sh | 23 +++++++++++++++++++++++ > 2 files changed, 25 insertions(+) > > diff --git a/diff.c b/diff.c > index f9709de7b45..f175019eb7a 100644 > --- a/diff.c > +++ b/diff.c > @@ -6044,6 +6044,8 @@ static void patch_id_consume(void *priv, char *line, unsigned long len) > struct patch_id_t *data = priv; > int new_len; > > + if (len > 12 && starts_with(line, "\\ ")) > + return; > new_len = remove_space(line, len); > > the_hash_algo->update_fn(data->ctx, line, new_len); > diff --git a/t/t3500-cherry.sh b/t/t3500-cherry.sh > index f038f34b7c0..2b8d9cb38ed 100755 > --- a/t/t3500-cherry.sh > +++ b/t/t3500-cherry.sh > @@ -55,4 +55,27 @@ test_expect_success \ > expr "$(echo $(git cherry master my-topic-branch) )" : "+ [^ ]* - .*" > ' > > +test_expect_success 'cherry ignores whitespace' ' > + git switch --orphan=upstream-with-space && > + test_commit initial file && > + >expect && > + git switch --create=feature-without-space && > + > + # A spaceless file on the feature branch. Expect a match upstream. > + printf space >file && > + git add file && > + git commit -m"file without space" && > + git log --format="- %H" -1 >>expect && > + > + # A further change. Should not match upstream. > + test_commit change file && > + git log --format="+ %H" -1 >>expect && > + > + git switch upstream-with-space && > + # Same as the spaceless file, just with spaces and on upstream. > + test_commit "file with space" file "s p a c e" file-with-space && > + git cherry upstream-with-space feature-without-space >actual && > + test_cmp expect actual > +' > + > test_done > -- > 2.28.0