How to determine which rule is causing a file to be ignored in Mercurial?

Question

Mercurial is presently ignoring a file which I believe shouldn't be ignored. The .hgignore file is remarkably large, and after a cursory read-through it's not obvious which rule(s) is/are the culprit.

Is there a way to get Mercurial to tell me which rules in the .hgignore (if any) match a file?

Answer 1

You can't do this out of the box, but you can write Mercurial extension for this.

I've written extension hg-isignored that can show you which rules in .hgignore match specified folder or file.

Installation

Clone extension source somewhere, i.e. in ~/.hgrc.d/hg-isignored folder:

hg clone https://hg@bitbucket.org/rpeshkov/hg-isignored ~/.hgrc.d/hg-isignored

Add extension in extensions section of your .hgrc file:

[extensions]
isignored=~/.hgrc.d/hg-isignored/hg-isignored.py

Now Mercurial will be able to use isignored command that's implemented by extension.

Usage

While you're in Mercurial repository, run command hg isignored PATH, where instead of PATH insert folder or file that you want to check, i.e. hg isignored readme.txt. Extension will tell you if specified PATH is ignored and will show you used rule.

Testing

Init

[~/hgtest]% hg init

No .hgignore

[~/hgtest]% touch readme.txt
[~/hgtest]% hg st  
? readme.txt
[~/hgtest]% hg isignored readme.txt
abort: .hgignore file not found

Added .hgignore

[~/hgtest]% echo "syntax: glob" > .hgignore
[~/hgtest]% echo "readme.txt" >> .hgignore
[~/hgtest]% hg st
? .hgignore
[~/hgtest]% hg isignored readme.txt
Path 'readme.txt' is ignored by:
relglob:readme.txt

Not ignored file

[~/hgtest]% touch readme2.txt
[~/hgtest]% hg isignored readme2.txt
Path 'readme2.txt' is not ignored

Ignore folder

[~/hgtest]% mkdir build
[~/hgtest]% touch build/keep.txt
[~/hgtest]% echo "build/" >> .hgignore
[~/hgtest]% hg st
? .hgignore
? readme2.txt
[~/hgtest]% hg isignored build
Path 'build' is ignored by:
relglob:build/
[~/hgtest]% hg isignored build/keep.txt
Path 'build/keep.txt' is ignored by:
relglob:build/

Ignore everything in folder

[~/hgtest]% echo "syntax: glob" > .hgignore
[~/hgtest]% echo "build/*" >> .hgignore
[~/hgtest]% hg st
? .hgignore
? readme.txt
? readme2.txt
[~/hgtest]% hg isignored build
Path 'build' is not ignored
[~/hgtest]% hg isignored build/keep.txt
Path 'build/keep.txt' is ignored by:
relglob:build/*