git clone google-pytype_-_2019-03-21_22-06-36.bundle -b master
Pytype checks and infers types for your Python code - without requiring typeannotations. Pytype can:
Pytype is a static analyzer, meaning it does not execute the code it runs on.
Thousands of projects at Google rely on pytype to keep their Python codewell-typed and error-free.
To quickly get started with type-checking a file or directory, run thefollowing, replacing
file_or_directory with your input:
pip install pytypepytype file_or_directory
To set up pytype on an entire package, add the following to a
setup.cfg filein the directory immediately above the package, replacing
package_name withthe package name:
[pytype]inputs = package_name
Now you can run the no-argument command
pytype to type-check the package. It'salso easy to add pytype to your automated testing; see thisexample of a GitHub project that runs pytype on Travis.
Finally, pytype generates files of inferred type information, located by defaultin
pytype_output/pyi. You can use this information to type-annotate thecorresponding source file, replacing
module.py with the file's import path:
merge-pyi -i module.py pytype_output/pyi/module.pyi
You need a Python 2.7 or 3.5+ interpreter to run pytype, as well as aninterpreter in
$PATH for the Python version of the code you're analyzing.
Pytype can be installed via pip. Note that the installation requires
setuptools. (If you're working in a virtualenv, these two packages shouldalready be present.)
pip install pytype
Or from the source code on GitHub.
git clone --recurse-submodules https://github.com/google/pytype.gitcd pytypepip install -U .
Instead of using
--recurse-submodules, you could also have run
git submodule initgit submodule update
```usage: pytype [options] input [input ...]
positional arguments: input file or directory to process```
-V, --python-version: Python version (major.minor) of the target code.Defaults to
-o, --output: The directory into which all pytype output goes, includinggenerated .pyi files. Defaults to
-d, --disable. Comma separated list of error names to ignore. Detailedexplanations of pytype's error names are in this doc.Defaults to empty.
For a full list of options, run
In addition to the above, you can direct pytype to use a custom typeshedinstallation instead of its own bundled copy by setting
For convenience, you can save your pytype configuration in a file. The configfile is an INI-style file with a
[pytype] section; if an explicit config fileis not supplied, pytype will look for a
[pytype] section in the first
setup.cfg file found by walking upwards from the current working directory.
Start off by generating a sample config file:
$ pytype --generate-config pytype.cfg
Now customize the file based on your local setup, keeping only the sections youneed. Directories may be relative to the location of the config file, which isuseful if you want to check in the config file as part of your project.
For example, suppose you have the following directory structure and want toanalyze package
~/repo1/foo, which depends on package
~/├── repo1│ └── foo│ ├── __init__.py│ └── file_to_check.py└── repo2 └── bar ├── __init__.py └── dependency.py
Here is the filled-in config file, which instructs pytype to type-check
~/repo1/foo as Python 3.6 code, look for packages in
~/repo2,and ignore attribute errors. Notice that the path to a package does not includethe package itself.
```$ cat ~/repo1/pytype.cfg
inputs = foo
python_version = 3.6
pythonpath = .: ~/repo2
disable = attribute-error```
We could've discovered that
~/repo2 needed to be added to the pythonpath byrunning pytype's broken dependency checker:
```$ pytype --config=~/repo1/pytype.cfg ~/repo1/foo/*.py --unresolved
Unresolved dependencies: bar.dependency```
Pytype ships with three scripts in addition to
merge-pyi, for merging type information from a .pyi file into aPython file.
pytd, a parser for .pyi files.
pytype-single, a debugging tool for pytype developers, which analyzes asingle Python file assuming that .pyi files have already been generated for allof its dependencies.
This is not an official Google product.