Command line usage¶

Once installed, isort exposes a command line utility for sorting, organizing, and formatting imports within Python and Cython source files.

To verify the tool is installed correctly, run isort from the command line and you should be given the available commands and the version of isort installed. For a list of all CLI options type isort --help or view the online configuration reference:

Formatting a Project¶

In general, isort is most commonly utilized across an entire projects source at once. The simplest way to do this is isort . or if using a src directory isort src. isort will automatically find all Python source files recursively and pick-up a configuration file placed at the root of your project if present. This can be combined with any command line configuration customizations such as specifying a profile to use (isort . --profile black).

Verifying a Project¶

The second most common usage of isort is verifying that imports within a project are formatted correctly (often within the context of a CI/CD system). The simplest way to accomplish this is using the check command line option: isort --check .. To improve the usefulness of errors when they do occur, this can be combined with the diff option: isort --check --diff ..

Single Source Files¶

Finally, isort can just as easily be ran against individual source files. Simply pass in a single or multiple source files to sort or validate (Example: isort setup.py).

Temporary Files¶

By default, when isort processes a source file, it writes the result to a sibling temporary file by appending .isorted to the source filename. If the content changes, this temporary file replaces the original. isort removes the temporary file when processing finishes and also attempts cleanup if sorting raises an exception.

If the process terminates before cleanup runs, the temporary file may remain. It can be removed after isort has stopped. Projects where abrupt termination is possible can ignore *.isorted files, or use the --overwrite-in-place option to avoid creating them, with a performance and memory usage penalty.

Multiple Projects¶

Running a single isort command across multiple projects, or source files spanning multiple projects, is highly discouraged. Instead it is recommended that an isort process (or command) is ran for each project independently. This is because isort creates an immutable config for each CLI instance.

# YES
isort project1
isort project2

# Also YES
isort project1/src project1/test
isort project2/src project2/test

# NO
isort project1 project2