# how to create a diff in old file new file format (for code reviews) 5 messages from 2010-12-14 to 2010-12-16. Participants: aerosmith, Michael J Gruber, Seshu Parvataneni. Thread: https://gitlist.dev/t/26043 ## aerosmith, 2010-12-14 00:07 Subject: how to create a diff in old file new file format (for code reviews) Message-ID: <1292285257962-5832810.post@n2.nabble.com> URL: https://gitlist.dev/e/1292285257962-5832810.post%40n2.nabble.com ``` Hi, I am trying to create a diff such that the original file (entire file) is saved something like file1.h.old and the new modified file as file1.h.new. I have read the various options for git-diff* tools but could not find one such utility. All I get is the removals and additions as a diff. Does anyone know how to create one with the help the available git utils? The only method that I can think of is to do everything manually. Any help w.r.t. this is really appreciated. Thanks in advance. -- View this message in context: http://git.661346.n2.nabble.com/how-to-create-a-diff-in-old-file-new-file-format-for-code-reviews-tp5832810p5832810.html Sent from the git mailing list archive at Nabble.com. ``` ## Michael J Gruber, 2010-12-14 09:17 Subject: Re: how to create a diff in old file new file format (for code reviews) Message-ID: <4D073619.2010103@drmicha.warpmail.net> URL: https://gitlist.dev/e/4D073619.2010103%40drmicha.warpmail.net In-Reply-To: <1292285257962-5832810.post@n2.nabble.com> ``` aerosmith venit, vidit, dixit 14.12.2010 01:07: > > Hi, > > I am trying to create a diff such that the original file (entire file) is > saved something like file1.h.old and the new modified file as file1.h.new. I > have read the various options for git-diff* tools but could not find one > such utility. All I get is the removals and additions as a diff. Does anyone > know how to create one with the help the available git utils? The only > method that I can think of is to do everything manually. Any help w.r.t. > this is really appreciated. Thanks in advance. You could script around this e.g. with an external diff-helper. The easiest way is to reuse difftool. For example, git difftool -y -x echo will give you pairs of names of temporary files for old/new, where is what you would give to "git diff" to specify what to diff. With the patch I'm sending in a minute, the helper you specify with "-x" can also access the basename easily, so that you could use "-x oldnew" with a script "oldnew" containing #!/bin/sh cp "$1" "$BASE".old cp "$2" "$BASE".new Even without the patch, you could use git difftool -y -x 'cp "$LOCAL" "$BASE".old; cp "$REMOTE" "$BASE.new"; #' (all on one line) directly. But this requires insider knowledge and may break some day. Cheers, Michael ``` ## Michael J Gruber, 2010-12-14 09:18 Subject: [PATCH 1/2] git-difftool.txt: correct the description of $BASE and describe $MERGED Message-ID: <0833a4451b70db4c4e0be5753be53e262a9c5628.1292317348.git.git@drmicha.warpmail.net> URL: https://gitlist.dev/e/0833a4451b70db4c4e0be5753be53e262a9c5628.1292317348.git.git%40drmicha.warpmail.net In-Reply-To: <4D073619.2010103@drmicha.warpmail.net> ``` Signed-off-by: Michael J Gruber --- Documentation/git-difftool.txt | 5 +++-- 1 files changed, 3 insertions(+), 2 deletions(-) diff --git a/Documentation/git-difftool.txt b/Documentation/git-difftool.txt index 6fffbc7..756d95d 100644 --- a/Documentation/git-difftool.txt +++ b/Documentation/git-difftool.txt @@ -56,8 +56,9 @@ the configured command line will be invoked with the following variables available: `$LOCAL` is set to the name of the temporary file containing the contents of the diff pre-image and `$REMOTE` is set to the name of the temporary file containing the contents -of the diff post-image. `$BASE` is provided for compatibility -with custom merge tool commands and has the same value as `$LOCAL`. +of the diff post-image. `$MERGED` is the name of the file which is +being compared. `$BASE` is provided for compatibility +with custom merge tool commands and has the same value as `$MERGED`. -x :: --extcmd=:: -- 1.7.3.3.739.g52f77.dirty ``` ## Michael J Gruber, 2010-12-14 09:18 Subject: [PATCH 2/2] difftool: provide basename to external tools Message-ID: <3a5944cb9af7b6b69dc0bdefdfd052b33fcd9a59.1292317348.git.git@drmicha.warpmail.net> URL: https://gitlist.dev/e/3a5944cb9af7b6b69dc0bdefdfd052b33fcd9a59.1292317348.git.git%40drmicha.warpmail.net In-Reply-To: <4D073619.2010103@drmicha.warpmail.net> ``` Currently, only configured diff helpers get the basename of the file being compared. Tools specified with "git difftool -x" only get the names of temporary files for the different versions. Export BASE so that an external tool can read the name from the environment. Rather than using a third argument, this avoids breaking existing scripts which may somewhat carelessly be using "$@" rather than "$1" "$2". Signed-off-by: Michael J Gruber --- Documentation/git-difftool.txt | 1 + git-difftool--helper.sh | 1 + 2 files changed, 2 insertions(+), 0 deletions(-) diff --git a/Documentation/git-difftool.txt b/Documentation/git-difftool.txt index 756d95d..db87f1d 100644 --- a/Documentation/git-difftool.txt +++ b/Documentation/git-difftool.txt @@ -65,6 +65,7 @@ with custom merge tool commands and has the same value as `$MERGED`. Specify a custom command for viewing diffs. 'git-difftool' ignores the configured defaults and runs `$command $LOCAL $REMOTE` when this option is specified. + Additionally, `$BASE` is set in the environment. -g:: --gui:: diff --git a/git-difftool--helper.sh b/git-difftool--helper.sh index 524f5ea..0594bf7 100755 --- a/git-difftool--helper.sh +++ b/git-difftool--helper.sh @@ -49,6 +49,7 @@ launch_merge_tool () { fi if use_ext_cmd; then + export BASE eval $GIT_DIFFTOOL_EXTCMD '"$LOCAL"' '"$REMOTE"' else run_merge_tool "$merge_tool" -- 1.7.3.3.739.g52f77.dirty ``` ## Seshu Parvataneni, 2010-12-16 03:33 Subject: Re: [solved] how to create a diff in old file new file format (for code reviews) Message-ID: <415120.5940.qm@web34306.mail.mud.yahoo.com> URL: https://gitlist.dev/e/415120.5940.qm%40web34306.mail.mud.yahoo.com In-Reply-To: <4D073619.2010103@drmicha.warpmail.net> ``` Hi Michael, Thanks very much for the reply. Your example with the difftool worked. This was what I was looking for. --- On Tue, 12/14/10, Michael J Gruber wrote: > From: Michael J Gruber > Subject: Re: how to create a diff in old file new file format (for code reviews) > To: "aerosmith" > Cc: git@vger.kernel.org > Date: Tuesday, December 14, 2010, 1:17 AM > aerosmith venit, vidit, dixit > 14.12.2010 01:07: > > > > Hi, > > > > I am trying to create a diff such that the original > file (entire file) is > > saved something like file1.h.old and the new modified > file as file1.h.new. I > > have read the various options for git-diff* tools but > could not find one > > such utility. All I get is the removals and additions > as a diff. Does anyone > > know how to create one with the help the available git > utils? The only > > method that I can think of is to do everything > manually. Any help w.r.t. > > this is really appreciated. Thanks in advance. > > You could script around this e.g. with an external > diff-helper. The > easiest way is to reuse difftool. For example, > > git difftool -y -x echo > > will give you pairs of names of temporary files for > old/new, where > is what you would give to "git diff" > to specify what to > diff. > > With the patch I'm sending in a minute, the helper you > specify with "-x" > can also access the basename easily, so that you could use > "-x oldnew" > with a script "oldnew" containing > > #!/bin/sh > cp "$1" "$BASE".old > cp "$2" "$BASE".new > > Even without the patch, you could use > > git difftool -y -x 'cp "$LOCAL" "$BASE".old; cp "$REMOTE" > "$BASE.new"; > #' > > (all on one line) directly. But this requires insider > knowledge and may > break some day. > > Cheers, > Michael > -- > To unsubscribe from this list: send the line "unsubscribe > git" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at  http://vger.kernel.org/majordomo-info.html > ```