I think it would be helpful to make this a separate patch.
The smaller a patch, the easier it is to accept.

And this in particular is a separate concept from this pull request's title.

That said, I think this is a good idea to enforce text files use lf line endings. It would be unfortunate for someone to submit a pull request where their editor auto-converted opened files. But * text=auto is a tad dangerous. Maybe instead list out the file types we expect? I would include all code files.

@ProgramMax How is it dangerous? I recommend reading the gitattributes documentation page for more information on what this does.

Other great reading material:

• https://stackoverflow.com/a/10855862/157971

Separate patch is a good idea, I will do that later. However it is likely that I close this PR and move it to the zlib-ng repository per a previous comment. This one is far too inactive and turnaround times for PRs are very long.

I read those before commenting. :) It is dangerous because it relies on Git to determine what is and isn't a text file. Git has gotten this wrong in the past. For example, in .png files: https://stackoverflow.com/questions/29435156/what-will-text-auto-eol-lf-in-gitattributes-do

Plus, some files which are text simply shouldn't be LF-formatted. For example, a Visual Studio solution or project file.

So I think it would make more sense to opt-in on the files which should be protected.

To your point, even if git assumes wrong for a file type, I think we should explicitly specify only the types it is getting wrong. This is a little more maintainable, as I feel confident the majority of file types will be handled correctly. So in your case we'd do something like:

* text=auto
*.png binary

The idea here is that the exclusive list will be much larger than the inclusive one. For the most part I trust Git, and as I've seen this work in many projects over many years with very few edge cases coming up, I plan to continue following this pattern in the .gitattributes I am contributing. I do appreciate your feedback though, however I think those cases should be handled explicitly.

On that note, does this repo even have PNG files?

Also in your linked SO question, they state that the issue you're talking about (using PNG as an example) was fixed in 2.10.0 of Git, per this answer. However this bug may not be relevant since my .gitattributes is doing * text=auto not * text=auto eol=lf. The latter is what the OP is doing in the SO question you linked.