astyle_py — Python wrapper around astyle
Artistic Style (astyle) is a source code indenter, formatter, and beautifier for the C, C++, C++/CLI, Objective‑C, C# and Java programming languages.
This project wraps astyle
in a Python package. The package can be used:
- as a pre-commit hook compatible with the pre-commit framework,
- as a console program,
- as a library, from other Python packages.
The main reason to use this Python wrapper, rather than native astyle
binaries, is that makes it easy for developers working on a project to have exactly the same version of astyle, regardless of their operating system. This prevents formatting differences which sometimes occur between different versions of astyle.
- Set up
pre-commit
for your project as described in https://pre-commit.com/#install. - Add
astyle_py
to your.pre-commit-config.yaml
file as follows. Note: avoid usingmain
as the revision.repos: - repo: https://github.com/igrr/astyle_py.git rev: v1.0.5 hooks: - id: astyle_py args: [--astyle-version=3.4.7 --style=linux]
Place the required astyle formatting options to the args
array. See the next section for details.
Use --dry-run
argument if you only want the pre-commit hook to report the formatting errors, and not fix them automatically.
If necessary, add verbose: true
option to see the output.
Use files:
option to configure the regex pattern used to match the files to be formatted. The default pattern is '^.*\.(c|cpp|cxx|h|hpp|inc)$'
. You can exclude certain files via additional arguments, as described in the next section.
Install the package from PyPI:
pip install astyle-py
Usage:
astyle_py [options] <files to format>
<files>
— list of files to process. By default,astyle_py
formats the files, modifying them in-place.[options]
— can be any of the formatting options, plus the following options are accepted:
--version
— print the version and exit.--astyle-version=<VER>
— choose the version of Astyle to use.--quiet
— don't print diagnostic messages; by default, the list of files which are formatted is printed tostderr
.--dry-run
— don't format the files, only check the formatting. Returns non-zero exit code if any file would change after formatting.
--options=<file>
— read more formatting options from the specified file. Empty lines and lines starting with#
are ignored.--exclude=<pattern>
— skip files matching the given pattern. Note that patterns use the syntax of Gitlab CODEOWNERS files.--exclude-list=<file>
— skip files matching the list of patterns specified in a file. Empty lines and lines starting with#
are ignored.
--rules=<file>
— read the formatting rules from the specified rules file. See Rules files section for details. This option is incompatible with--options
,--exclude
,--exclude-list
.
This package can be used as a library to implement custom formatting tools. See sample.py for an example.
See http://astyle.sourceforge.net/astyle.html for the details on Astyle formatting options.
Note that this wrapper doesn't implement the options from "Other options" and "Command Line Only" categories, except for those listed above.
Option --rules=<file>
allows loading the formatting options from a rules file in YAML format. The rules file can specify different formatting rules for different parts of the project. This can be useful for monorepos which contain libraries written with different formatting conventions.
The rules file consists of sections (rules). For each section the following keywords may be specified:
version:
Version of Astyle to useinclude:
List of files name patterns to include in this rule. Pattern syntax of Gitlab CODEOWNERS files is used. Required.check:
If set tofalse
, the files covered by this rule will be ignored and not checked/formatted. Optional, default istrue
.options:
A string specifying the formatting options for files covered by this rule.
If the file path matches multiple rules, the latest rule is applied. If the file path doesn't match any rule, the options from the special DEFAULT
rule are used.
Here is an example of a rules file:
DEFAULT:
# These formatting options will be used by default
options: "--style=otbs --indent=spaces=4 --convert-tabs"
thirdparty_lib_1: # The section name is arbitrary
# Override formatting rules for the files in a certain directory
options: "--style=linux"
include:
- "/thirdparty/lib1/"
code_to_ignore_for_now:
# Ignore files in some other directories
check: false
include:
- "/src/component1/"
- "/src/component2/"
- "tests/" # matches a subdirectory 'tests' anywhere in the source tree
This python wrapper bundles multiple copies of Astyle, you can choose which one to use:
- In the CLI: via
--astyle-version=VERSION
argument - When using astyle_py as a library: by passing the version to
Astyle()
constructor
The following versions are supported:
- 3.1 — used by default, unless a different version is specified
- 3.4.7
To simplify distribution of astyle, it is compiled to WebAssembly (astyle_py/libastyle.wasm) and executed using wasmtime runtime via its Python bindings. This package should work on all operating systems supported by wasmtime — at the time of writing these are:
- x86_64 (amd64) Windows, Linux, macOS
- aarch64 (arm64) Linux and macOS
Other project which wraps astyle into a Python package include:
- https://github.com/timonwong/pyastyle — unmaintained at the time of writing, uses native Astyle binaries
- https://github.com/Freed-Wu/astyle-wheel/ — actively maintained, uses native Astyle binaries
Please see CONTRIBUTING.md for details.
- The source code in this repository is Copyright (c) 2020-2022 Ivan Grokhotkov and licensed under the MIT license.
libastyle.wasm
binaries bundled under astyle_py/lib directory are built from Artistic Style project, Copyright (c) 2018 by Jim Pattee jimp03@email.com, also licensed under the MIT license. See http://astyle.sourceforge.net/ for details.
Thanks to André Simon for maintaining Astyle project!