CVS style diffs in git

Question

Is there any way to make the output format of git diffs like cvs style diffs? I find git diffs to be less readable. Also, the git diffs appearing in more are annoying - how can I disable this?

This really should have been two separate questions. – Keith Thompson Jan 15 '13 at 00:04 — Keith Thompson, Jan 15 '13 at 00:04

Keith Thompson · Answer 1 · 2013-01-15T00:02:20.480

git diff uses the "universal" format, diff -u, by default. cvs diff uses the older standard diff format (deleted lines marked with <, added lines marked with >, no context around each difference).

You can get a "context diff" using git diff -c, or git diff -C5, for example, to get 5 lines of context rather than the default 3.

diff --normal (at least if you're using GNU diffutils) will produce an old-style diff, but git diff doesn't seem to recognize the --normal option.

Personally, I find context diffs much more readable than old-style diffs, so I've never found the need to use old-style diffs with git diff. Try git diff -c (along with haggai_e's suggestion to disable the pager).

If you really want the old-style diffs (<, >, no context), there's probably a way to do it.

EDIT :

If git diff doesn't do what you want, you can extract copies of the revisions of the file and use whatever diff tool you like on them. My own get-versions tool can extract multiple versions of a file from git (or from RCS or CVS).

And here's another solution, though it's a bit more complicated. As an example, I've cloned the git repo for git itself. If I want to compare two successive versions of the top-level README file, I can do this:

$ diff --normal <(git show 779d7e93773a0dcf918dc77023511fdc68161bd8:README) \
                <(git show 71ce415dc088f19a0b8d6c8567dfdd6d851842b2:README)
24,26c24,25
< compatible with the GPLv2).
< It was originally written by Linus Torvalds with help of a group of
< hackers around the net. It is currently maintained by Junio C Hamano.
---
> compatible with the GPLv2). It was originally written by Linus
> Torvalds with help of a group of hackers around the net.
$

It would be easy enough to wrap this in a small script.

Note that the file path following the : (README in the above example) is relative to the root of the repository, not to the current directory. You can precede the name with ./ to make to make it relative to the current directory. (The latter might not work with some older versions of git.)

I don't know what version of git this is pertinent to, but for "git version 1.7.7.6", git diff -c is not valid, but git diff -Un (n for number of context lines) works. git diff -U0 is almost giving me what I want, but I still don't like the appearance. This is all a matter of preference thing really, while you prefer context diffs, I don't as it is just a sanity check before commit thing for me. If I need context diffs I'm using meld. Cheers for the tip however. Again, I'd mark up if it would allow me to. — user1207217, Feb 20 '12 at 13:49
See http://stackoverflow.com/questions/11331582/how-to-make-git-diff-output-normal-diff-format-non-unified-non-context - here we can pass the --normal option. Cheers — user1207217, Jan 14 '13 at 23:55
@user1207217: I updated my answer (just before I read the link in the above comment). — Keith Thompson, Jan 15 '13 at 00:03

score 5 · Answer 2 · answered Feb 13 '12 at 16:23

5

You can disable the pager by setting core.pager to an empty string:

git config --global core.pager ''

answered Feb 13 '12 at 16:23

haggai_e

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I think the usual way to do that is to set it to `cat`. – Keith Thompson Feb 13 '12 at 20:14
Setting it to cat does seem tidier. – user1207217 Feb 20 '12 at 13:50
@user1207217 You need some reputation before you can vote (and I can't find the link to the site explaining the reputation anymore since the last SO layout change), but can accept the answer. – Rudi Feb 26 '12 at 11:34

score 1 · Accepted Answer · edited May 23 '17 at 12:18

Try playing with standard diff formatting:

git difftool -y -x "diff --unchanged-group-format='' --old-line-format='< %L' --new-line-format='> %L'"

This gives CVS-like newlines and oldlines, with no context, but it doesn't insert the extras between groups of different lines. Not quite sure how to achieve the rest, given I don't know the extent to which you would like CVS-like formatting.

man diff

For more information

Also see

git difftool -y -x "diff -n"

But I doubt this does what you want. If this does work for you, to make it work every time with git diff, see Configuring diff tool with .gitconfig?, which references http://jeetworks.com/node/90 in the accepted answer.

This combined with http://stackoverflow.com/questions/11331582/how-to-make-git-diff-output-normal-diff-format-non-unified-non-context gives me what I want. Cheers — user1207217, Jan 14 '13 at 23:55

CVS style diffs in git

3 Answers3