mypy-runner 0.1.9

Run mypy with options to filter errors and colorize output

Ease your way into static type checking by focusing on a small set of problems at a time.

It can be quite challenging to get an existing code base to pass mypy’s checks, even at its most lenient settings, and unfortunately, until you do you can’t use mypy as part of your CI/CD process.

mypy-runner lets you gradually introduce type checking by identifying a subset of files and errors to check:

• choose a set of files and errors to check

• get tests passing and enforce them in your CI and pre-commit hooks

• repeat

Features

mypy-runner adds the following features to mypy:

• Display colorized output

• Convert specific errors to warnings

• Filter specific errors and warnings

Options

usage: mypyrun [-h] [--list] [--daemon] [--select SELECT] [--ignore IGNORE]
               [--warn WARN] [--no-color] [--show-ignored] [--show-error-keys]
               [--options OPTIONS]
               [files [files ...]]

positional arguments:
  files                 Files to isolate (triggers use of 'active'options for
                        these files)

optional arguments:
  -h, --help            show this help message and exit
  --list                list error codes
  --daemon, -d          run in daemon mode (dmypy run)
  --select SELECT, -s SELECT
                        Errors to check (comma separated)
  --ignore IGNORE, -i IGNORE
                        Errors to skip (comma separated)
  --warn WARN, -w WARN  Errors to convert into warnings (comma separated)
  --no-color            do not colorize output
  --show-ignored, -x    Show errors that have been ignored (darker if using
                        color)
  --show-error-keys     Show error key for each line
  --options OPTIONS, -o OPTIONS
                        Override the default options to use the
                        namedconfiguration section (e.g. pass --options=foo to
                        use the [mypyrun-foo] section)

As with tools like flake8, you use specific error codes to enable or disable error output. Errors that are ignored or converted into warnings will not trigger a non-zero exit status. To see the list of error codes and their regex pattern, run mypyrun --list.

Configuration

mypyrun looks for a [mypyrun] section in either mypy.ini or mypyrun.ini.

Here’s an example configuration file:

[mypyrun]

# run dmypy instead of mypy
daemon = true

# only display these errors
select =
    not_defined,
    return_expected,
    return_not_expected,
    incompatible_subclass_attr,

# all other errors are warnings
warn = *

# filter errors generated from these paths:
exclude =
    thirdparty/*,

# pass these paths to mypy
paths =
    arnold/python,
    houdini/python,
    katana/python,
    mari/python,
    maya/python,
    nuke/python,
    python/packages,