How to compare two files not in repo using git

Question

I'd like to compare two css files which are not in any git repository. Is there such a functionality in git?

What if I wanted to use, say, the `--patience` flag? Do you know a **diff(1)** that can do that? — SamB, Aug 05 '12 at 19:35
related: https://stackoverflow.com/questions/855767/can-i-use-git-diff-on-untracked-files?rq=1 — slm, Jan 23 '18 at 03:50

score 284 · Accepted Answer · edited May 23 '17 at 11:54

284

git's diff is more functional than the standard unix diff. I often want to do this and since this question ranks highly on google, I want this answer to show up.

This question: How to use git diff --color-words outside a Git repository?

Shows how to use git to diff files where at least one of them is not in the repository by using --no-index:

git diff --no-index file1.txt file2.txt

It doesn't matter which one is tracked by git and which is not - one or both can be untracked, eg:

$ date > x
$ sleep 2
$ date > y
$ git diff --color-words --no-index x y
diff --git a/x b/y
index 6b10c7c..70f036c 100644
--- a/x
+++ a/y
@@ -1 + 1 @@
Wed Jun 10 10:57:45|10:57:47 EDT 2013

The color can't be shown here so I separated the changes with a pipe in the example.

edited May 23 '17 at 11:54

Community

1
1

answered Jun 19 '13 at 15:02

Kyle Burton

26,788
9
50
60

17

If you wanted this behavior default, you could add an alias to your `.bashrc` file (or whatever you use): `alias diff="git diff --no-index"` – counterbeing Jun 30 '15 at 20:30
1

FYI: On Git for Windows there was a [bug (#2123)](https://github.com/git-for-windows/git/issues/2123) that "--no-index" was not respected. This was fixed in Git for Windows v2.21.0 (February 26th 2019). – StackzOfZtuff Jun 27 '19 at 11:18
What does row "index 6b10c7c..70f036c 100644" mean? I am comparing 2 binaries, they differ, but that is the only row with difference... – Lukas Salich Sep 10 '19 at 17:43
hi @LukasSalich it looks like that line format might be documented by git (eg: https://git-scm.com/docs/diff-format) git's diff doesn't attempt to diff binaries afaik, so I'm guessing that line means they differ, the two SHAs where a change was identified and then the permissions of the file. – Kyle Burton Sep 22 '19 at 17:46
3

Note that you don't have to specify `--no-index` if you're doing this outside of any Git repository. – SnakE Nov 20 '20 at 11:23
I use git diff on 2 files (in my working directory) where they are both version-controlled. So theoretically, i can exclude --no-index. But strange, output is empty. Once i put --no-index, it shows diff output. – Nick Wills Dec 19 '22 at 11:16

score 6 · Answer 2 · edited May 16 '18 at 09:13

6

diff -u

will give similar unified context output to git's diff.

edited May 16 '18 at 09:13

4b0

21,981
30
95
142

answered May 16 '18 at 09:02

james

61
1
1

1

It does not do nice coloring or use a pager, however. – Xiong Chiamiov Aug 14 '18 at 18:47
It does not allow a nice word diff, either (`git diff --word-diff`). – Stefan van den Akker Jul 25 '19 at 18:20

score 1 · Answer 3 · answered Jul 19 '12 at 13:10

1

Just use the diff command:

diff file1.ext file2.ext

answered Jul 19 '12 at 13:10

edwardmp

6,339
5
50
77

2

Hmkay, I tried this but in my opinion, the output was just nonsense... Maybe I was wrong... – Cedric Reichenbach Jul 19 '12 at 17:49
you can run some GUI tool that will provide better view, like gvimdiff, kompare or similar – Eugene Sajine Jul 19 '12 at 21:41

How to compare two files not in repo using git

3 Answers3

Linked