Import ignores from .gitignore

[sandstrom]

Problem

Right now there is a lot of duplication between our yaml-lint ignore directives, and our .gitignore files. It would be neat if we could import from gitignore, via e.g. import_ignore: .gitignore.

How it could work

Something like:

# using the default rules
extends: default

# skip everything ignored by .gitignore
import_ignore: ".gitignore"

rules:
  octal-values: enable
  # …

Since I think yaml-lint is using the same ignore format as .gitignore, maybe it's fairly easy to import? Would also allow keeping the ignore list in a separate file.

Open Questions

• How should conflicting rules be solved? Ideally with "last rule wins". That way one can override or adjust directives imported from .gitignore if needed.

[adrienverge]

I understand the use-case. It could be done using a conf option ignore-from-file: .gitignore, mutually exclusive with ignore. Do you want to implement it?

[sandstrom]

@adrienverge Mutually exclusive would preclude making adjustments to the ignore directives, or overriding !keep-me.file. Are there technical reasons making it more complicated to allow mixing ignore with import_ignore?

I'd love to, but I haven't spent many hours in Python. So not sure I could.

[ndrwnaguib]

@adrienverge I'm willing to implement that. Would you assign me and give me few tips? :))

Are you sure tho that you want it to be mutually exclusive with ignore? Because, what if you want to ignore linting for specific files but not ignoring committing them (considering the .gitignore case)

I think the lines to be modified would be:

yamllint/yamllint/config.py

Lines 100 to 105 in 8f68248

	if 'ignore' in conf:
	if not isinstance(conf['ignore'], str):
	raise YamlLintConfigError(
	'invalid config: ignore should contain file patterns')
	self.ignore = pathspec.PathSpec.from_lines(
	'gitwildmatch', conf['ignore'].splitlines())

Confirm, please?

[adrienverge]

@adrienverge Mutually exclusive would preclude making adjustments to the ignore directives, or overriding !keep-me.file. Are there technical reasons making it more complicated to allow mixing ignore with import_ignore?

Being able to make adjustments makes sense, I'm not opposed to it. It's just that it's more complex to implement: more code and more tests are needed.

About the option name, I'd prefer staying consistent with other configuration keys. For example something like ignore-from-file: .gitignore, or even better: ignore-from-files: [.gitignore, other-file].

@adrienverge I'm willing to implement that. Would you assign me and give me few tips? :))

Great! I suggest looking carefully at a few commits that implemented new features, and reproduce the same. Note that they need documentation, test every corner case, and have a commit message that describes what they do. Please save my time and open the PR once it's 100% ready.