PyCharm 2023.1 Help

Run/Debug Configuration: Mocha

Create: Run | Edit Configurations | Add New Configuration | Mocha

In this dialog, create configurations for running and debugging JavaScript unit tests using the Mocha test framework.

Before you start

  1. Make sure you have Node.js on your computer.

  2. Make sure the JavaScript and TypeScript and Node.js required plugins are enabled on the Settings | Plugins page, tab Installed, see Managing plugins for details.

Mocha-specific configuration settings

Item

Description

Node.js interpreter

In this field, specify the Node.js interpreter to use. Choose one of the configured interpreters or click the Browse button and configure a new one as described in Configuring a local Node.js interpreter. If you choose the Project alias, PyCharm will automatically use the project default interpreter from the Node interpreter field on the Node.js page.

Node options

In this field, type the Node.js-specific command-line options to be passed to the Node.js executable file. See Node Parameters for details.

Working directory

In this field, specify the working directory of the application. By default, the Working directory field shows the project root folder. To change this predefined setting, specify the path to the desired folder.

Environment variables

In this field, specify the environment variables for the Node.js executable file, if applicable. Click Browse the Browse button to the right of the field and configure a list of variables in the Environment Variables dialog, that opens:

  • To define a new variable, click the Add button and specify the variable name and value.

  • To discard a variable definition, select it in the list and click the Remove button.

  • Click OK, when ready

The definitions of variables are displayed in the Environment variables read-only field with semicolons as separators, for example:

  • NODE_PATH: A :-separated list of directories prefixed to the module search path.

  • NODE_MODULE_CONTEXTS: Set to 1 to load modules in their own global contexts.

  • NODE_DISABLE_COLORS: Set to 1 to disable colors in the REPL.

Mocha package

In this field, specify the Mocha installation home /npm/node_modules/mocha. If you installed Mocha regularly through the Node Package Manager, PyCharm detects the Mocha installation home itself. Alternatively, type the path to executable file manually, or click Browse the Browse button and select the location in the dialog, that opens.

User interface

From this list, choose the interface according to which the tests in the test folder are written. PyCharm will recognize only tests that comply with the chosen interface. If during test execution PyCharm runs against a test of another interface, the test session will be canceled with an error. This means that all the tests in the specified test folder must be written according to the same interface and this interface must be chosen from the list.

Extra Mocha options

In this field, specify additional Mocha command-line options. For example, add a --watch flag to turn on the autotest-like runner.

As a result, any test in the current run configuration restarts automatically on changing the related source code, without clicking the Rerun button Rerun.

Tests

In this area, specify the tests to be executed. The available options are:

  • All in directory: choose this option to run all the tests from the files stored in a folder and specify the path to this folder in the Test directory field. To look for tests in the subfolders under the specified directory, select the Include subdirectories checkbox.

  • File pattern: choose this option to look for tests in all the files with the names that match a certain mask and specify the mask in the Test file pattern field, for example, *.test.js.

    If the files with tests are stored in a test folder, specify the path to this folder in the pattern relative to the working directory, for example, ./folder1/folder2/test/*.test.js.

  • Test file: choose this option to run only the tests from one file and specify the path to this file in the Test file field.

  • Suite: choose this option to run individual suites from a test file and specify the path to this file in the Test file field. Click the Browse button in the Suite name field and configure a list of suites to run using the Add and Remove buttons.

  • Test: choose this option to run individual tests from a test file and specify the path to this file in the Test file field. Click the Browse button in the Test name field and configure a list of tests to run using the Add and Remove buttons.

Docker container settings

This read-only field shows port and volume bindings. Click the Expand button to open the command preview.

Node.js with Docker: run/debug configuration, Docker container settings

Docker Compose

In this area, specify the commands and options to be passed to Docker Compose. Accept the default settings or click the Expand button and specify custom ones, for example, custom Docker Compose flags, like --rm or --service-ports. Learn more from the Docker official website.

Check the Command Preview.

Common settings

When you edit a run configuration (but not a run configuration template), you can specify the following options:

Item

Description

Name

Specify a name for the run configuration to quickly identify it among others when editing or running.

Allow multiple instances

Allow running multiple instances of this run configuration in parallel.

By default, it is disabled, and when you start this configuration while another instance is still running, PyCharm suggests stopping the running instance and starting another one. This is helpful when a run configuration consumes a lot of resources and there is no good reason to run multiple instances.

Store as project file

Save the file with the run configuration settings to share it with other team members. The default location is .idea/runConfigurations. However, if you do not want to share the .idea directory, you can save the configuration to any other directory within the project.

By default, it is disabled, and PyCharm stores run configuration settings in .idea/workspace.xml.

Toolbar

The tree view of run/debug configurations has a toolbar that helps you manage configurations available in your project as well as adjust default configurations templates.

Item

Shortcut

Description

the Add button

Alt+Insert

Create a run/debug configuration.

the Remove button

Alt+Delete

Delete the selected run/debug configuration. Note that you cannot delete default configurations.

Copy

Control+D

Create a copy of the selected run/debug configuration. Note that you create copies of default configurations.

Save configuration

The button is displayed only when you select a temporary configuration. Click this button to save a temporary configuration as permanent.

Move into new folder / Create new folder

Move into new folder / Create new folder. You can group run/debug configurations by placing them into folders.

To create a folder, select the configurations within a category, click Folder, and specify the folder name. If only a category is in focus, an empty folder is created.

Then, to move a configuration into a folder, between the folders or out of a folder, use drag or Move Up and Move Down buttons.

To remove grouping, select a folder and click Remove Configuration.

Sort configurations

Click this button to sort configurations in the alphabetical order.

Before launch

In this area, you can specify tasks to be performed before starting the selected run/debug configuration. The tasks are performed in the order they appear in the list.

Item

Shortcut

Description

the Add button

Alt+Insert

Click this icon to add one of the following available tasks:

  • Launch Web Browser: select this option to have a browser started. In the dialog that opens, select the type of the browser and provide the start URL. Also, specify if you want the browser be launched with JavaScript debugger.

  • Run External tool: select to run an external application. In the dialog that opens, select one or multiple applications you want to run. If it is not defined in PyCharm yet, add its definition. For more information, see External tools and External Tools.

  • Run Another Configuration: select to execute another run/debug configuration and wait until it finishes before starting the current configuration. If you want to run several configurations in parallel, use a compound run/debug configuration.

  • Run File Watchers: select this option to have PyCharm apply all the currently active File Watchers.

  • Run Remote External tool: adds a remote SSH external tool.

  • Run Grunt task: select this option to run a Grunt task.

    In the Grunt task dialog that opens, specify the Gruntfile.js where the required task is defined, select the task to execute, and specify the arguments to pass to the Grunt tool.

    Specify the location of the Node.js interpreter, the parameters to pass to it, and the path to the grunt-cli package.

  • Run Gulp task: select this option to run a Gulp task.

    In the Gulp task dialog that opens, specify the Gulpfile.js where the required task is defined, select the task to execute, and specify the arguments to pass to the Gulp tool.

    Specify the location of the Node.js interpreter, the parameters to pass to it, and the path to the gulp package.

  • Run npm Script: select this option to execute an npm script.

    In the NPM Script dialog that opens, specify the npm run/debug configuration settings.

  • Compile TypeScript: select to run the built-in TypeScript compiler and thus make sure that all the changes you made to your TypeScript code are reflected in the generated JavaScript files. In the TypeScript Compile Settings dialog that opens, select or clear the Check errors checkbox to configure the behaviour of the compiler in case any errors are detected:

    • If the Check errors checkbox is selected, the compiler will show all the errors and the run configuration will not start.

    • If the Check errors checkbox is cleared, the compiler will show all the detected errors but the run configuration still will be launched.

  • Generate CoffeeScript Source Maps: select this option to generate the source maps for your CoffeeScript sources. In the dialog that opens, specify where your CoffeeScript source files are located.

the Remove button

Alt+Delete

Click this icon to remove the selected task from the list.

Edit

Enter

Click this icon to edit the selected task. Make the necessary changes in the dialog that opens.

Method up/Method down

Alt+ArrowUp/Alt+ArrowDown

Click these icons to move the selected task one line up or down in the list. The tasks are performed in the order that they appear in the list.

Show this page

Select this checkbox to show the run/debug configuration settings prior to actually starting the run/debug configuration.

Activate tool window

By default this checkbox is selected and the Run or the Debug tool window opens when you start the run/debug configuration.

Otherwise, if the checkbox is cleared, the tool window is hidden. However, when the configuration is running, you can open the corresponding tool window for it yourself by pressing Alt+4 or Alt+5.

Last modified: 21 June 2023