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Version: 2.23 (prerelease)

mypy

The MyPy Python type checker (http://mypy-lang.org/).

This version of Pants uses mypy version 1.4.1 by default. Use a dedicated lockfile and the install_from_resolve option to control this.

Backend: pants.backend.python.typecheck.mypy

Config section: [mypy]

Basic options​

args​

--mypy-args="[<shell_str>, <shell_str>, ...]"
PANTS_MYPY_ARGS
pants.toml
[mypy]
args = [
    <shell_str>,
    <shell_str>,
    ...,
]
default: []

Arguments to pass directly to MyPy, e.g. --mypy-args='--python-version 3.7 --disallow-any-expr'.

skip​

--[no-]mypy-skip
PANTS_MYPY_SKIP
pants.toml
[mypy]
skip = <bool>
default: False

If true, don't use MyPy when running pants check.

Advanced options​

config​

--mypy-config=<file_option>
PANTS_MYPY_CONFIG
pants.toml
[mypy]
config = <file_option>
default: None

Path to a config file understood by MyPy (https://mypy.readthedocs.io/en/stable/config_file.html).

Setting this option will disable [mypy].config_discovery. Use this option if the config is located in a non-standard location.

config_discovery​

--[no-]mypy-config-discovery
PANTS_MYPY_CONFIG_DISCOVERY
pants.toml
[mypy]
config_discovery = <bool>
default: True

If true, Pants will include any relevant config files during runs (mypy.ini, .mypy.ini, and setup.cfg).

Use [mypy].config instead if your config is in a non-standard location.

console_script​

--mypy-console-script=<str>
PANTS_MYPY_CONSOLE_SCRIPT
pants.toml
[mypy]
console_script = <str>
default: mypy

The console script for the tool. Using this option is generally preferable to (and mutually exclusive with) specifying an --entry-point since console script names have a higher expectation of staying stable across releases of the tool. Usually, you will not want to change this from the default.

entry_point​

--mypy-entry-point=<str>
PANTS_MYPY_ENTRY_POINT
pants.toml
[mypy]
entry_point = <str>
default: None

The entry point for the tool. Generally you only want to use this option if the tool does not offer a --console-script (which this option is mutually exclusive with). Usually, you will not want to change this from the default.

install_from_resolve​

--mypy-install-from-resolve=<str>
PANTS_MYPY_INSTALL_FROM_RESOLVE
pants.toml
[mypy]
install_from_resolve = <str>
default: None

If specified, install the tool using the lockfile for this named resolve.

This resolve must be defined in [python].resolves, as described in https://www.pantsbuild.org/2.23/docs/python/overview/lockfiles#lockfiles-for-tools.

The resolve's entire lockfile will be installed, unless specific requirements are listed via the requirements option, in which case only those requirements will be installed. This is useful if you don't want to invalidate the tool's outputs when the resolve incurs changes to unrelated requirements.

If unspecified, and the lockfile option is unset, the tool will be installed using the default lockfile shipped with Pants, which uses mypy version 1.4.1.

If unspecified, and the lockfile option is set, the tool will use the custom mypy "tool lockfile" generated from the version and extra_requirements options. But note that this mechanism is deprecated.

interpreter_constraints​

--mypy-interpreter-constraints="['<str>', '<str>', ...]"
PANTS_MYPY_INTERPRETER_CONSTRAINTS
pants.toml
[mypy]
interpreter_constraints = [
    '<str>',
    '<str>',
    ...,
]
default: 
[
  "CPython>=3.7,<4"
]

Python interpreter constraints for this tool.

requirements​

--mypy-requirements="['<str>', '<str>', ...]"
PANTS_MYPY_REQUIREMENTS
pants.toml
[mypy]
requirements = [
    '<str>',
    '<str>',
    ...,
]
default: []

If install_from_resolve is specified, install these requirements, at the versions provided by the specified resolve's lockfile.

Values can be pip-style requirements (e.g., tool or tool==1.2.3 or tool>=1.2.3), or addresses of python_requirement targets (or targets that generate or depend on python_requirement targets). Make sure to use the // prefix to refer to targets using their full address from the root (e.g. //3rdparty/python:tool). This is necessary to distinguish address specs from local or VCS requirements.

The lockfile will be validated against the requirements - if a lockfile doesn't provide the requirement (at a suitable version, if the requirement specifies version constraints) Pants will error.

If unspecified, install the entire lockfile.

source_plugins​

--mypy-source-plugins="[<target_option>, <target_option>, ...]"
PANTS_MYPY_SOURCE_PLUGINS
pants.toml
[mypy]
source_plugins = [
    <target_option>,
    <target_option>,
    ...,
]
default: []

An optional list of python_sources target addresses to load first-party plugins.

You must also set plugins = path.to.module in your mypy.ini, and set the [mypy].config option in your pants.toml.

To instead load third-party plugins, set the option [mypy].install_from_resolve to a resolve whose lockfile includes those plugins, and set the plugins option in mypy.ini. See https://www.pantsbuild.org/2.23/docs/python/goals/check.

Deprecated options​

None

None