PathSpec

pathspec is a utility library for pattern matching of file paths. So far this only includes Git's wildmatch pattern matching which itself is derived from Rsync's wildmatch. Git uses wildmatch for its gitignore files.

Tutorial

Say you have a "Projects" directory and you want to back it up, but only certain files, and ignore others depending on certain conditions:

>>> import pathspec
>>> # The gitignore-style patterns for files to select, but we're including
>>> # instead of ignoring.
>>> spec_text = """
...
... # This is a comment because the line begins with a hash: "#"
...
... # Include several project directories (and all descendants) relative to
... # the current directory. To reference a directory you must end with a
... # slash: "/"
... /project-a/
... /project-b/
... /project-c/
...
... # Patterns can be negated by prefixing with exclamation mark: "!"
...
... # Ignore temporary files beginning or ending with "~" and ending with
... # ".swp".
... !~*
... !*~
... !*.swp
...
... # These are python projects so ignore compiled python files from
... # testing.
... !*.pyc
...
... # Ignore the build directories but only directly under the project
... # directories.
... !/*/build/
...
... """

We want to use the GitWildMatchPattern class to compile our patterns. The PathSpec class provides an interface around pattern implementations:

>>> spec = pathspec.PathSpec.from_lines(pathspec.patterns.GitWildMatchPattern, spec_text.splitlines())

That may be a mouthful but it allows for additional patterns to be implemented in the future without them having to deal with anything but matching the paths sent to them. GitWildMatchPattern is the implementation of the actual pattern which internally gets converted into a regular expression. PathSpec is a simple wrapper around a list of compiled patterns.

To make things simpler, we can use the registered name for a pattern class instead of always having to provide a reference to the class itself. The GitWildMatchPattern class is registered as gitwildmatch:

>>> spec = pathspec.PathSpec.from_lines('gitwildmatch', spec_text.splitlines())

If we wanted to manually compile the patterns we can just do the following:

>>> patterns = map(pathspec.patterns.GitWildMatchPattern, spec_text.splitlines())
>>> spec = PathSpec(patterns)

PathSpec.from_lines() is simply a class method which does just that.

If you want to load the patterns from file, you can pass the file instance directly as well:

>>> with open('patterns.list', 'r') as fh:
>>>     spec = pathspec.PathSpec.from_lines('gitwildmatch', fh)

You can perform matching on a whole directory tree with:

>>> matches = spec.match_tree('path/to/directory')

Or you can perform matching on a specific set of file paths with:

>>> matches = spec.match_files(file_paths)

Or check to see if an individual file matches:

>>> is_matched = spec.match_file(file_path)

There is a specialized class, pathspec.GitIgnoreSpec, which more closely implements the behavior of gitignore. This uses GitWildMatchPattern pattern by default and handles some edge cases differently from the generic PathSpec class. GitIgnoreSpec can be used without specifying the pattern factory:

>>> spec = pathspec.GitIgnoreSpec.from_lines(spec_text.splitlines())

License

pathspec is licensed under the Mozilla Public License Version 2.0. See LICENSE or the FAQ for more information.

In summary, you may use pathspec with any closed or open source project without affecting the license of the larger work so long as you:

• give credit where credit is due,
• and release any custom changes made to pathspec.

Source

The source code for pathspec is available from the GitHub repo cpburnz/python-pathspec.

Installation

pathspec is available for install through PyPI:

pip install pathspec

pathspec can also be built from source. The following packages will be required:

• build (>=0.6.0)

pathspec can then be built and installed with:

python -m build
pip install dist/pathspec-*-py3-none-any.whl

Documentation

Documentation for pathspec is available on Read the Docs.

Other Languages

The related project pathspec-ruby (by highb) provides a similar library as a Ruby gem.