git and CR vs LF (but NOT CRLF)

Question

This may sound like a redundant question (and may very well be a redundnant question) but I can't find the answer. Here's the situation:

My application is creating text files that have CR's as line endings. More specifically I'm not explicitly setting the line endings to CR, it just happens to be the output of the command I'm using to get the text body. Of course I could manually convert the CR's to LF's but I don't want to if I can avoid it.

Git's treating these files as a single line (e.g. during a diff). I have determined via this test repository that the line-endings are the cause: https://github.com/jfletcher4d/diff-test

I don't actually care what the line-endings are on the file system. It's not important, at least not yet (I may eventually care if I need to import these files, right now it's only export). But I do not want to convert the CR's to LFs in my application if I can avoid it, for performance reasons as well as anal-retentativeness reasons :) I.e. this isn't a question of how to create text files but, rather, how to force every text file in the repo to have only LFs.

Can git be configured to change all line endings to LF, even if the files are committed with CR in them?

I'm on Windows, using TortoiseGit and msysgit (and a little TortoiseSVN on the side) interchangeably while I learn git, if that matters.

Answer 1

Git doesn’t appear to support CR line endings, so I would write a filter to convert the newlines. The files in the work tree will have CR line endings, and they will be transparently converted to LF when they are indexed. The filter has two parts: “clean” checks the files in, and “smudge” checks the files out.

Use this in .git/config:

[filter "cr"]
    clean = tr '\\r' '\\n'
    smudge = tr '\\n' '\\r'

And .git/info/attributes (or .gitattributes if it should be versioned)

* filter=cr

Note that this automatically makes git-diff happy, since it will use the “clean” version.

Just remember to set the pattern to just the files you need, or binary files will be corrupted and all text files will check out with CR line endings.

Also note that if the filter is not configured, it will silently fail, so add the config line when setting up a new copy of the repository.

Answer 2

FWIW, I ended up converting the line endings to LF on the local side of things. It ended up being the simpler/less buggy solution.