# Re: [PATCH] git-diff: don't add trailing blanks (i.e., do what GNU diff -u now does) 6 messages from 2006-12-17 to 2006-12-18. Participants: Jakub Narebski, Junio C Hamano, Jim Meyering, Johannes Schindelin, Linus Torvalds. Thread: https://gitlist.dev/t/43447 ## Jim Meyering, 2006-12-17 19:32 Subject: [PATCH] git-diff: don't add trailing blanks (i.e., do what GNU diff -u now does) Message-ID: <87y7p6nwsh.fsf@rho.meyering.net> URL: https://gitlist.dev/e/87y7p6nwsh.fsf%40rho.meyering.net ``` You may recall that GNU diff -u changed recently so that it no longer outputs any trailing space unless the input data has it. This means that blank context lines are now blank also in diff -u output. Before, they would have a single trailing space. Then, git was changed to allow that new diff output format. Now that git-diff generates output using its internal diff, its output is no longer identical to what you get when using GNU diff. This patch makes the output of git-diff the same as GNU diff's. Signed-off-by: Jim Meyering --- t/t4016-diff-trailing-space.sh | 31 +++++++++++++++++++++++++++++++ xdiff/xutils.c | 3 +++ 2 files changed, 34 insertions(+), 0 deletions(-) diff --git a/t/t4016-diff-trailing-space.sh b/t/t4016-diff-trailing-space.sh new file mode 100755 index 0000000..95c4674 --- /dev/null +++ b/t/t4016-diff-trailing-space.sh @@ -0,0 +1,31 @@ +#!/bin/bash +# +# Copyright (c) Jim Meyering +# +test_description='diff does not add trailing spaces' + +. ./test-lib.sh + +cat <<\EOF > exp || +diff --git a/f b/f +index 5f6a263..8cb8bae 100644 +--- a/f ++++ b/f +@@ -1,2 +1,2 @@ + +-x ++y +EOF +exit 1 + +test_expect_success \ + "$test_description" \ + '(echo; echo x) > f && + git-add f && + git-commit -q -m. f && + (echo; echo y) > f && + git-diff f > actual && + cmp exp actual + ' + +test_done diff --git a/xdiff/xutils.c b/xdiff/xutils.c index 1b899f3..8b7380a 100644 --- a/xdiff/xutils.c +++ b/xdiff/xutils.c @@ -51,6 +51,9 @@ int xdl_emit_diffrec(char const *rec, long size, char const *pre, long psize, mb[0].size = psize; mb[1].ptr = (char *) rec; mb[1].size = size; + /* Don't emit a trailing space for an empty context line. */ + if (size == 1 && rec[0] == '\n' && psize == 1 && *pre == ' ') + mb[0].size = 0; if (size > 0 && rec[size - 1] != '\n') { mb[2].ptr = (char *) "\n\\ No newline at end of file\n"; mb[2].size = strlen(mb[2].ptr); -- ``` ## Linus Torvalds, 2006-12-17 20:00 Subject: Re: [PATCH] git-diff: don't add trailing blanks (i.e., do what GNU diff -u now does) Message-ID: URL: https://gitlist.dev/e/Pine.LNX.4.64.0612171200290.3479%40woody.osdl.org In-Reply-To: <87y7p6nwsh.fsf@rho.meyering.net> ``` On Sun, 17 Dec 2006, Jim Meyering wrote: > > You may recall that GNU diff -u changed recently so that it no > longer outputs any trailing space unless the input data has it. I still consider that to be a bug in GNU "diff -u". We work around that bug when applying patches, but I don't think we should replicate it. ``` ## Junio C Hamano, 2006-12-17 20:09 Subject: Re: [PATCH] git-diff: don't add trailing blanks (i.e., do what GNU diff -u now does) Message-ID: <7vtzzu5lp1.fsf@assigned-by-dhcp.cox.net> URL: https://gitlist.dev/e/7vtzzu5lp1.fsf%40assigned-by-dhcp.cox.net In-Reply-To: ``` Linus Torvalds writes: > On Sun, 17 Dec 2006, Jim Meyering wrote: >> >> You may recall that GNU diff -u changed recently so that it no >> longer outputs any trailing space unless the input data has it. > > I still consider that to be a bug in GNU "diff -u". > > We work around that bug when applying patches, but I don't think we should > replicate it. Me neither. ``` ## Jim Meyering, 2006-12-17 20:36 Subject: Re: [PATCH] git-diff: don't add trailing blanks (i.e., do what GNU diff -u now does) Message-ID: <87psainttt.fsf@rho.meyering.net> URL: https://gitlist.dev/e/87psainttt.fsf%40rho.meyering.net In-Reply-To: <7vtzzu5lp1.fsf@assigned-by-dhcp.cox.net> ``` Junio C Hamano wrote: > Linus Torvalds writes: >> On Sun, 17 Dec 2006, Jim Meyering wrote: >>> You may recall that GNU diff -u changed recently so that it no >>> longer outputs any trailing space unless the input data has it. >> >> I still consider that to be a bug in GNU "diff -u". >> >> We work around that bug when applying patches, but I don't think we should >> replicate it. > > Me neither. I can't say I didn't expect this. ``` ## Jakub Narebski, 2006-12-17 20:54 Subject: Re: [PATCH] git-diff: don't add trailing blanks (i.e., do what GNU diff -u now does) Message-ID: URL: https://gitlist.dev/e/em4all%24b2c%241%40sea.gmane.org In-Reply-To: <7vtzzu5lp1.fsf@assigned-by-dhcp.cox.net> ``` Junio C Hamano wrote: > Linus Torvalds writes: > >> On Sun, 17 Dec 2006, Jim Meyering wrote: >>> >>> You may recall that GNU diff -u changed recently so that it no >>> longer outputs any trailing space unless the input data has it. >> >> I still consider that to be a bug in GNU "diff -u". >> >> We work around that bug when applying patches, but I don't think we should >> replicate it. > > Me neither. Perhaps with --gnu-diff-compatibility then? -- Jakub Narebski Warsaw, Poland ShadeHawk on #git ``` ## Johannes Schindelin, 2006-12-18 12:06 Subject: Re: [PATCH] git-diff: don't add trailing blanks (i.e., do what GNU diff -u now does) Message-ID: URL: https://gitlist.dev/e/Pine.LNX.4.63.0612181305500.3635%40wbgn013.biozentrum.uni-wuerzburg.de In-Reply-To: ``` Hi, On Sun, 17 Dec 2006, Jakub Narebski wrote: > Junio C Hamano wrote: > > > Linus Torvalds writes: > > > >> On Sun, 17 Dec 2006, Jim Meyering wrote: > >>> > >>> You may recall that GNU diff -u changed recently so that it no > >>> longer outputs any trailing space unless the input data has it. > >> > >> I still consider that to be a bug in GNU "diff -u". > >> > >> We work around that bug when applying patches, but I don't think we should > >> replicate it. > > > > Me neither. > > Perhaps with --gnu-diff-compatibility then? Rather --braindead-gnu-bug-compatibility. Ciao, Dscho ```