A simple plugin that allows running mypy from PyCharm and navigate between errors

dropbox dropbox Last update: Feb 21, 2024

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mypy-PyCharm-plugin

The plugin provides a simple terminal to run fast mypy daemon from PyCharm with a single click or hotkey and easily navigate through type checking results. The idea of the mypy terminal is different from the normal PyCharm type checking that highlights the errors in a current file. The mypy terminal shows errors in all files in your project (even in those not currently open). Also mypy provides a bit stricter type checking and is tunable by various flags and config settings.

mypy plugin screenshot

Installation

The plugin can be installed directly from JetBrains plugin repository

Installing developer build

Requirements for building the plugin:

  • Oracle JDK 8
    • Either javac should be available on your PATH or JAVA_HOME environment variable should contain your JDK installation path

Requirements for running the plugin:

  • Mypy
    • The plugin runs the mypy executable to check types

Installation steps:

  1. Clone the GitHub repository.

  2. Open the cloned directory in your terminal and build it using this shell command:

    ./gradlew clean buildPlugin
    

    or on Windows:

    gradlew clean buildPlugin
    

    The plugin file mypy-PyCharm-plugin.zip will be built in build/distributions.

  3. In PyCharm go to Preferences -> Plugins -> Install plugins from disk -> Select the plugin file -> Restart PyCharm when prompted.

  4. After restart you should find the plugin in View -> Tool windows -> Mypy terminal.

Configuration

Normally, plugin should not require any configuration steps. However, sometimes plugin cannot find dmypy command because it doesn't have the full environment. If the plugin says something like dmypy command not found when you try to run mypy, then this is likely the cause. In this case right click in mypy terminal in PyCharm -> Configure plugin. Then enter the path where mypy is installed as PATH suffix. If you are using a virtual environment, this will look like /my/project/bin (or C:\my\project\Scripts if you are on Windows). If necessary, you can also configure mypy command to use your custom .ini file and flags.

Usage

You can pin the terminal to either side of PyCharm window: click on window toolbar → Move. The current default is bottom, which works best if you typically have only a few errors. If you are working on legacy code with many mypy errors, you may want to use the ‘left’ or ‘right’ setting. Finally, if you have multiple monitors you might find the floating mode convenient.

Currently supported features and keyboard shortcuts:

  • Show/hide mypy terminal: Ctrl + Shift + X
  • Run mypy type checking: Ctrl + Shift + M or click Run
  • Go to error: click on error line, or use Ctrl + Shift + <arrows> to navigate between errors
  • Copy current error: right click → Copy error text, or Ctrl + Shift + C
  • Collapse/expand errors: click on file name in the mypy terminal, or Ctrl + Shift + Enter when a file name is selected
  • Sometimes mypy shows links to online documentation; to follow links use Alt + <click>

Contributing

External contributions to the project should be subject to Dropbox Contributor License Agreement (CLA).

  1. Open the repository in IntelliJ 2019.1 or newer via File -> Open. IntelliJ will import it as a Gradle project.

  2. Set up a project JDK via File -> Project Structure -> Project -> Project SDK. JDK 8 or newer is required.

  3. Build and run the plugin via a Gradle task runIde available as View -> Tool Windows -> Gradle -> Tasks -> intellij -> runIde.


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