pathspec: Path Specification

pathspec is a utility library for pattern matching of file paths. So far this only includes gitignore style pattern matching which itself incorporates POSIX glob patterns.

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 = """
...
... # 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 GitIgnorePattern class to compile our patterns, and the PathSpec to provide an iterface around them:

>>> spec = pathspec.PathSpec.from_lines(pathspec.GitIgnorePattern, spec.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. GitIgnorePattern 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.

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

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

PathSpec.from_lines() is simply a dumb class method to do just that.

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

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

Source

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

Installation

pathspec requires the following packages:

• setuptools

pathspec can be installed from source with:

python setup.py install

pathspec is also available for install through PyPI:

pip install pathspec