'git status' shows changed files, but 'git diff' doesn't

Question

I added the file to the index:

git add file_name

And then ran:

git diff --cached file_name

You can see the description of git diff here.

If you need to undo your git add, then please see here: How do I undo 'git add' before commit?

For me, it had something to do with file permissions. Someone with Mac/Linux on my project seems to commit some files with non-default permissions which my Windows Git client failed to reproduce.

The solution for me was to tell Git to ignore file permissions:

git config core.fileMode false

Other insight: How do I make Git ignore file mode (chmod) changes?

There are a few reasons why git status might show a difference but git diff might not.

• The mode (permission bits) of the file changed-- for example, from 777 to 700.

• The line feed style changed from CRLF (DOS) to LF (UNIX)

The easiest way to find out what happened is to run git format-patch HEAD^ and see what the generated patch says.

I had an issue where hundreds of line endings were modified by some program and git diff listed all source files as changed. After fixing the line endings, git status still listed the files as modified.

I was able to fix this problem by adding all files to the index and then resetting the index.

git add -A
git reset

core.filemode was set to false.

As already noted in a previous answer, this situation may arise due to line-ending problems (CR/LF vs. LF). I solved this problem (under Git version 2.22.0) with this command:

git add --renormalize .

According to the manual:

       --renormalize
           Apply the "clean" process freshly to all tracked files to
           forcibly add them again to the index. This is useful after
           changing core.autocrlf configuration or the text attribute in
           order to correct files added with wrong CRLF/LF line endings.
           This option implies -u.

I suspect there is something wrong either with your Git installation or your repository.

Try running:

GIT_TRACE=2 git <command>

See if you get anything useful. If that doesn't help, just use strace and see what's going wrong:

strace git <command>

I had a similar problem: git diff would show differences, but git diff <filename> would not. It turned out that I set LESS to a string including -F (--quit-if-one-screen). Removing that flag solved the problem.