PYDOCSTYLE

NAME

pydocstyle - pydocstyle Documentation

pydocstyle is a static analysis tool for checking compliance with Python docstring conventions.

pydocstyle supports most of PEP 257 out of the box, but it should not be considered a reference implementation.

pydocstyle supports Python 3.7 through 3.11.

Although pydocstyle is tries to be compatible with Python 3.6, it is not tested.

1.

Install

pip install pydocstyle

2.

Run

$ pydocstyle test.py
test.py:18 in private nested class `meta`:
D101: Docstring missing
test.py:27 in public function `get_user`:
D300: Use """triple double quotes""" (found '''-quotes)
test:75 in public function `init_database`:
D201: No blank lines allowed before function docstring (found 1)
...

3.

Fix your code :)

Contents:

USAGE

Installation

Use pip or easy_install:

pip install pydocstyle

Alternatively, you can use pydocstyle.py source file directly - it is self-contained.

Command Line Interface

Usage

Usage: pydocstyle [options] [<file|dir>...]

Options:
--version show program's version number and exit
-h, --help show this help message and exit
-e, --explain show explanation of each error
-s, --source show source for each error
-d, --debug print debug information
-v, --verbose print status information
--count print total number of errors to stdout
--config=<path> use given config file and disable config discovery
--match=<pattern> check only files that exactly match <pattern> regular
expression; default is --match='(?!test_).*\.py' which
matches files that don't start with 'test_' but end
with '.py'
--match-dir=<pattern>
search only dirs that exactly match <pattern> regular
expression; default is --match-dir='[ˆ\.].*', which
matches all dirs that don't start with a dot
--ignore-decorators=<decorators>
ignore any functions or methods that are decorated by
a function with a name fitting the <decorators>
regular expression; default is --ignore-decorators=''
which does not ignore any decorated functions.

Note:
When using --match, --match-dir or --ignore-decorators consider
whether you should use a single quote (') or a double quote ("),
depending on your OS, Shell, etc.

Error Check Options:
Only one of --select, --ignore or --convention can be specified. If
none is specified, defaults to `--convention=pep257`. These three
options select the "basic list" of error codes to check. If you wish
to change that list (for example, if you selected a known convention
but wish to ignore a specific error from it or add a new one) you can
use `--add-[ignore/select]` in order to do so.

--select=<codes> choose the basic list of checked errors by specifying
which errors to check for (with a list of comma-
separated error codes or prefixes). for example:
--select=D101,D2
--ignore=<codes> choose the basic list of checked errors by specifying
which errors to ignore out of all of the available
error codes (with a list of comma-separated error
codes or prefixes). for example: --ignore=D101,D2
--convention=<name>
choose the basic list of checked errors by specifying
an existing convention. Possible conventions: pep257,
numpy, google.
--add-select=<codes>
add extra error codes to check to the basic list of
errors previously set by --select, --ignore or
--convention.
--add-ignore=<codes>
ignore extra error codes by removing them from the
basic list previously set by --select, --ignore or
--convention.

NOTE:

When using any of the --select, --ignore, --add-select, or --add-ignore command line flags, it is possible to pass a prefix for an error code. It will be expanded so that any code beginning with that prefix will match. For example, running the command pydocstyle --ignore=D4 will ignore all docstring content issues as their error codes beginning with "D4" (i.e. D400, D401, D402, D403, and D404).

Return Code

Configuration Files

pydocstyle supports ini-like and toml configuration files. In order for pydocstyle to use a configuration file automatically, it must be named one of the following options.

	•		setup.cfg
	•		tox.ini
	•		.pydocstyle
	•		.pydocstyle.ini
	•		.pydocstylerc
	•		.pydocstylerc.ini
	•		pyproject.toml

When searching for a configuration file, pydocstyle looks for one of the file specified above in that exact order. ini-like configuration files must have a [pydocstyle] section while toml configuration files must have a [tool.pydocstyle] section. If a configuration file was not found, pydocstyle keeps looking for one up the directory tree until one is found or uses the default configuration.

NOTE:

toml configuration file support is only enabled if the toml python package is installed. You can ensure that this is the case by installing the pydocstyle[toml] optional dependency.

NOTE:

For backwards compatibility purposes, pydocstyle supports configuration files named .pep257, as well as section header [pep257]. However, these are considered deprecated and support will be removed in the next major version.

Available Options

Not all configuration options are available in the configuration files. Available options are:

	•		convention
	•		select
	•		ignore
	•		add_select
	•		add_ignore
	•		match
	•		match_dir
	•		ignore_decorators
	•		property_decorators

See the Usage section for more information.

Inheritance

By default, when finding a configuration file, pydocstyle tries to inherit the parent directory's configuration and merge them to the local ones.

The merge process is as follows:

	•		If one of select, ignore or convention was specified in the child configuration - Ignores the parent configuration and set the new error codes to check. Otherwise, simply copies the parent checked error codes.
	•		If add-ignore or add-select were specified, adds or removes the specified error codes from the checked error codes list.
	•		If match or match-dir were specified - use them. Otherwise, use the parent's.

In order to disable this (useful for configuration files located in your repo's root), simply add inherit=false to your configuration file.

NOTE:

If any of select, ignore or convention were specified in the CLI, the configuration files will take no part in choosing which error codes will be checked. match and match-dir will still take effect.

Example

[pydocstyle]
inherit = false
ignore = D100,D203,D405
match = .*\.py

In-file configuration

pydocstyle supports inline commenting to skip specific checks on specific functions or methods. The supported comments that can be added are:

	1.		"# noqa" skips all checks.
	2.		"# noqa: D102,D203" can be used to skip specific checks. Note that this is compatible with skips from flake8, e.g. # noqa: D102,E501,D203.

For example, this will skip the check for a period at the end of a function docstring:

>>> def bad_function(): # noqa: D400
... """Omit a period in the docstring as an exception"""
... pass

Usage with the pre-commit git hooks framework

pydocstyle can be included as a hook for pre-commit. The easiest way to get started is to add this configuration to your .pre-commit-config.yaml:

- repo: https://github.com/pycqa/pydocstyle
rev: 0.0.0 # pick a git hash / tag to point to
hooks:
- id: pydocstyle

See the pre-commit docs for how to customize this configuration.

Checked-in python files will be passed as positional arguments so no need to use --match=*.py. You can also use command line arguments instead of configuration files to achieve the same effect with less files.

- id: pydocstyle
args:
- --ignore=D100,D203,D405
# or multiline
- |-
--select=
D101,
D2

ERROR CODES

Grouping

Default conventions

Not all error codes are checked for by default. There are three conventions that may be used by pydocstyle: pep257, numpy and google.

The pep257 convention (specified in PEP257), which is enabled by default in pydocstyle, checks for all of the above errors except for D203, D212, D213, D214, D215, D404, D405, D406, D407, D408, D409, D410, D411, D413, D415, D416 and D417.

The numpy convention added in v2.0.0 supports the numpydoc docstring standard. This checks all of the errors except for D107, D203, D212, D213, D402, D413, D415, D416, and D417.

The google convention added in v4.0.0 supports the Google Python Style Guide. This checks for all the errors except D203, D204, D213, D215, D400, D401, D404, D406, D407, D408, D409 and D413.

These conventions may be specified using --convention=<name> when running pydocstyle from the command line or by specifying the convention in a configuration file. See the Usage section for more details.

NOTE:

It makes no sense to check the same docstring for both numpy and google conventions. Therefore, if we successfully detect that a docstring is in the numpy style, we don't check it for google.

The reason numpy style takes precedence over google is that the heuristics of detecting it are better, and we don't want to enforce users to provide external hints to pydocstyle in order to let it know which style docstrings are written in.

Publicity

The D1xx group of errors deals with missing docstring in public constructs: modules, classes, methods, etc. It is important to note how publicity is determined and what its effects are.

How publicity is determined

Publicity for all constructs is determined as follows: a construct is considered public if -

	1.		Its immediate parent is public and
	2.		Its name does not start with a single or double underscore.

a.

Note, names that start and end with a double underscore are public (e.g. __init__.py).

A construct's immediate parent is the construct that contains it. For example, a method's parent is a class object. A class' parent is usually a module, but might also be a function, method, etc. A module can either have no parent, or it can have a parent that is a package.

In order for a construct to be considered public, its immediate parent must also be public. Since this definition is recursive, it means that all of its parents need to be public. The corollary is that if a construct is considered private, then all of its descendants are also considered private. For example, a class called _Foo is considered private. A method bar in _Foo is also considered private since its parent is a private class, even though its name does not begin with a single underscore.

Note, a module's parent is recursively checked upward until we reach a directory in sys.path to avoid considering the complete filepath of a module. For example, consider the module /_foo/bar/baz.py. If PYTHONPATH is set to /, then baz.py is private. If PYTHONPATH is set to /_foo/, then baz.py is public.

Modules are parsed to look if __all__ is defined. If so, only those top level constructs are considered public. The parser looks for __all__ defined as a literal list or tuple. As the parser doesn't execute the module, any mutation of __all__ will not be considered.

How publicity affects error reports

The immediate effect of a construct being determined as private is that no D1xx errors will be reported for it (or its children, as the previous section explains). A private method, for instance, will not generate a D102 error, even if it has no docstring.

However, it is important to note that while docstring are optional for private construct, they are still required to adhere to your style guide. So if a private module _foo.py does not have a docstring, it will not generate a D100 error, but if it does have a docstring, that docstring might generate other errors.

pydocstyle is a rename and continuation of pep257, a project created by Vladimir Keleshev.

Maintained by Amir Rachum and Sambhav Kothari.

AUTHOR

Amir Rachum

COPYRIGHT

2023, Amir Rachum, Sambhav Kothari