This is style50, a tool with which code can be checked against the CS50 style guide.
pip install style50
In order to style check C, C++, or Java code, a recent version (
astyle must be installed.
astyle may be downloaded here.
Along with most of CS50's command line tools,
style50 supports being run on Windows but only via the Linux Subsystem in Windows 10. After launching it,
style50 can be installed using the
pip command above.
usage: style50 [-h] [-o MODE] [-v] [-V] [-E] [-i PATTERN] file [file ...] positional arguments: file file or directory to lint optional arguments: -h, --help show this help message and exit -o MODE, --output MODE output mode, which can be character (default), split, unified, score, or json -v, --verbose print full tracebacks of errors -V, --version show program's version number and exit -E, --extensions print supported file extensions (as JSON list) and exit -i PATTERN, --ignore PATTERN paths/patterns to be ignored
unified modes output character-based, side-by-side, and unified (respectively) diffs between the inputted file and the correctly styled version.
score outputs the raw percentage of correct (unchanged) lines, while
json outputs a json object containing information pertinent to the CS50 IDE plugin (coming soon).
style50 currently supports the following languages:
Adding a new language
Adding a new language is very simple. Language checks are encoded as classes which inherit from the
StyleCheck base class (see
style50/languages.py for more real-world examples). The following is a template for style checks which allows style50 to check the imaginary FooBar language for style.
import re from style50 import StyleCheck, Style50 class FooBar(StyleCheck): # REQUIRED: this property informs style50 what file extensions this # check should be run on (in this case, all .fb and .foobar files) extensions = ["fb", "foobar"] # REQUIRED: should return a correctly styled version of `code` def style(self, code): # All FooBar code is perfectly styled return code # OPTIONAL: should return the number of comments in `code`. # If this function is not defined, `style50` will not warn the student about # too few comments def count_comments(self, code): # A real-world, check would need to worry about not counting '#' in string-literals return len(re.findall(r"#.*", code))
All classes which inherit from
StyleCheck are automatically registered with
Style50 class, making style50 easily extensible. Adding the following to the above code creates a script which checks the code that
style50 already does as well as FooBar programs.
# Style check the current directory, printing a unified diff Style50(["."], output="unified").run()