Metadata-Version: 2.1
Name: pytype
Version: 2021.4.15
Summary: Python type inferencer
Home-page: https://google.github.io/pytype
Maintainer: Google
Maintainer-email: pytype@googlegroups.com
License: Apache 2.0
Project-URL: Code, https://github.com/google/pytype
Project-URL: Issue Tracker, https://github.com/google/pytype/issues
Project-URL: Documentation, https://google.github.io/pytype
Description: 
        [![CI](https://github.com/google/pytype/workflows/CI/badge.svg?branch=master)](https://github.com/google/pytype/actions)
        [![PyPI - Wheel](https://img.shields.io/pypi/wheel/pytype)](https://pypi.org/project/pytype/#files)
        
        # pytype - 🦆✔
        
        Pytype checks and infers types for your Python code - without requiring type
        annotations. Pytype can:
        
        * Lint plain Python code, flagging common mistakes such as misspelled attribute
        names, incorrect function calls, and [much more][error-classes], even across
        file boundaries.
        * Enforce user-provided [type annotations][pep-484]. While annotations are
        optional for pytype, it will check and apply them where present.
        * Generate type annotations in standalone files ("[pyi files][pyi-stub-files]"),
        which can be merged back into the Python source with a provided
        [merge-pyi][merge-pyi] tool.
        
        Pytype is a static analyzer; it does not execute the code it runs on.
        
        Thousands of projects at Google rely on pytype to keep their Python code
        well-typed and error-free.
        
        For more information, check out the [user guide][user-guide], [FAQ][faq], or
        [supported features][supported-features].
        
        ## How is pytype different from other type checkers?
        
        1. Pytype uses **inference** instead of gradual typing. This means it will
        infer types on code even when the code has no type hints on it. So it can
        detect issues with code like this, which other type checkers would miss:
        
            ```python
            def f():
                return "PyCon"
            def g():
                return f() + 2019
        
            # pytype: line 4, in g: unsupported operand type(s) for +: 'str'
            # and 'int' [unsupported-operands]
            ```
        
        1. Pytype is **lenient** instead of strict. That means it allows all
        operations that succeed at runtime and don't contradict annotations. For
        instance, this code will pass as safe in pytype, but fail in other type
        checkers, which assign types to variables as soon as they are initialized:
        
            ```python
            from typing import List
            def get_list() -> List[str]:
                lst = ["PyCon"]
                lst.append(2019)
                return [str(x) for x in lst]
        
            # mypy: line 4: error: Argument 1 to "append" of "list" has
            # incompatible type "int"; expected "str"
            ```
        
        Also see the corresponding [FAQ entry][faq-diff].
        
        ## Quickstart
        
        To quickly get started with type-checking a file or directory, run the
        following, replacing `file_or_directory` with your input:
        
        ```shell
        pip install pytype
        pytype file_or_directory
        ```
        
        To set up pytype on an entire package, add the following to a `setup.cfg` file
        in the directory immediately above the package, replacing `package_name` with
        the package name:
        
        ```
        [pytype]
        inputs = package_name
        ```
        
        Now you can run the no-argument command `pytype` to type-check the package. It's
        also easy to add pytype to your automated testing; see this
        [example][importlab-travis] of a GitHub project that runs pytype on Travis.
        
        Finally, pytype generates files of inferred type information, located by default
        in `.pytype/pyi`. You can use this information to type-annotate the
        corresponding source file:
        
        ```shell
        merge-pyi -i <filepath>.py .pytype/pyi/<filename>.pyi
        ```
        
        ## Requirements
        
        You need a Python 3.6-3.8 interpreter to run pytype, as well as an
        interpreter in `$PATH` for the Python version of the code you're analyzing
        (supported: 2.7, 3.5-3.8).
        
        Platform support:
        
        * Pytype is currently developed and tested on Linux\*, which is the main supported
          platform.
        * Installation on MacOSX requires OSX 10.7 or higher and Xcode v8 or higher.
        * Windows is currently not supported unless you use [WSL][wsl].
        
        <sub>\*
        Note: On Alpine Linux, installing may fail due to issues with upstream
        dependencies.  See the details of [this issue][scikit-build-issue] for a
        possible fix.
        </sub>
        
        ## Installing
        
        Pytype can be installed via pip. Note that the installation requires `wheel`
        and `setuptools`. (If you're working in a virtualenv, these two packages should
        already be present.)
        
        ```shell
        pip install pytype
        ```
        
        Or from the source code [on GitHub][github].
        
        ```shell
        git clone --recurse-submodules https://github.com/google/pytype.git
        cd pytype
        pip install .
        ```
        
        Instead of using `--recurse-submodules`, you could also have run
        
        ```shell
        git submodule init
        git submodule update
        ```
        
        in the `pytype` directory. To edit the code and have your edits tracked live,
        replace the pip install command with:
        
        ```shell
        pip install -e .
        ```
        
        ### Installing on WSL
        
        Follow the steps above, but make sure you have the correct libraries first:
        
        ```shell
        sudo apt install build-essential python3-dev libpython3-dev
        ```
        
        ## Usage
        
        ```
        usage: pytype [options] input [input ...]
        
        positional arguments:
          input                 file or directory to process
        ```
        
        Common options:
        
        * `-V, --python-version`: Python version (major.minor) of the target code.
          Defaults to the version that pytype is running under.
        * `-o, --output`: The directory into which all pytype output goes, including
          generated .pyi files. Defaults to `.pytype`.
        * `-d, --disable`. Comma or space separated list of error names to ignore.
          Detailed explanations of pytype's error names are in
          [this doc][error-classes]. Defaults to empty.
        
        For a full list of options, run `pytype --help`.
        
        In addition to the above, you can direct pytype to use a custom typeshed
        installation instead of its own bundled copy by setting `$TYPESHED_HOME`.
        
        ### Config File
        
        For convenience, you can save your pytype configuration in a file. The config
        file is an INI-style file with a `[pytype]` section; if an explicit config file
        is 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:
        
        ```shell
        $ pytype --generate-config pytype.cfg
        ```
        
        Now customize the file based on your local setup, keeping only the sections you
        need. Directories may be relative to the location of the config file, which is
        useful 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 to
        analyze package `~/repo1/foo`, which depends on package `~/repo2/bar`:
        
        ```
        ~/
        ├── 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 `~/repo1` and `~/repo2`,
        and ignore attribute errors. Notice that the path to a package does not include
        the package itself.
        
        ```
        $ cat ~/repo1/pytype.cfg
        
        # NOTE: All relative paths are relative to the location of this file.
        
        [pytype]
        
        # Space-separated list of files or directories to process.
        inputs =
            foo
        
        # Python version (major.minor) of the target code.
        python_version = 3.6
        
        # Paths to source code directories, separated by ':'.
        pythonpath =
            .:
            ~/repo2
        
        # Comma or space separated list of error names to ignore.
        disable =
            attribute-error
        ```
        
        We could've discovered that `~/repo2` needed to be added to the pythonpath by
        running pytype's broken dependency checker:
        
        ```
        $ pytype --config=~/repo1/pytype.cfg ~/repo1/foo/*.py --unresolved
        
        Unresolved dependencies:
          bar.dependency
        ```
        
        ### Subtools
        
        Pytype ships with a few scripts in addition to `pytype` itself:
        
        * `annotate-ast`, an in-progress type annotator for ASTs.
        * [`merge-pyi`][merge-pyi], for merging type information from a .pyi file into a
        Python file.
        * `pytd-tool`, a parser for .pyi files.
        * `pytype-single`, a debugging tool for pytype developers, which analyzes a
        single Python file assuming that .pyi files have already been generated for all
        of its dependencies.
        * `pyxref`, a cross references generator.
        
        ## 2021 Roadmap
        
        * Python 3.9 support
        * Better performance on large files
        * Support for numerical libraries
        
        ## License
        [Apache 2.0][license]
        
        ## Disclaimer
        This is not an official Google product.
        
        [error-classes]: https://github.com/google/pytype/blob/master/docs/errors.md
        [faq]: https://github.com/google/pytype/blob/master/docs/faq.md
        [faq-diff]: https://github.com/google/pytype/blob/master/docs/faq.md#how-is-pytype-different-from-other-type-checkers
        [github]: https://github.com/google/pytype/
        [importlab-travis]: https://github.com/google/importlab/blob/master/.travis.yml
        [license]: https://github.com/google/pytype/blob/master/LICENSE
        [merge-pyi]: https://github.com/google/pytype/tree/master/pytype/tools/merge_pyi
        [pep-484]: https://www.python.org/dev/peps/pep-0484
        [pyi-stub-files]: https://github.com/google/pytype/blob/master/docs/user_guide.md#pyi-stub-files
        [scikit-build-issue]: https://github.com/scikit-build/ninja-python-distributions/issues/27
        [supported-features]: https://github.com/google/pytype/blob/master/docs/support.md
        [user-guide]: https://github.com/google/pytype/blob/master/docs/user_guide.md
        [wsl]: https://docs.microsoft.com/en-us/windows/wsl/faq
        
Platform: UNKNOWN
Classifier: Development Status :: 5 - Production/Stable
Classifier: Intended Audience :: Developers
Classifier: License :: OSI Approved :: Apache Software License
Classifier: Programming Language :: Python
Classifier: Programming Language :: Python :: 3.6
Classifier: Programming Language :: Python :: 3.7
Classifier: Programming Language :: Python :: 3.8
Classifier: Programming Language :: Python :: 3.9
Classifier: Programming Language :: Python :: Implementation :: CPython
Classifier: Topic :: Software Development
Requires-Python: <3.10,>=3.6
Description-Content-Type: text/markdown
