Dec 28, 2025 · Coverage.py is a tool for measuring code coverage of Python programs. It monitors your program, noting which parts of the code have been executed, then analyzes the source to identify …

When you install coverage.py, a command-line script called coverage is placed on your path. To help with multi-version installs, it will also create a coverage3 alias, and a coverage-X.Y alias, depending …

This patch configures Python to start coverage automatically, and will apply to processes created with subprocess, os.system(), or one of the execv or spawnv family of functions.

Reporting: Coverage.py combines the results of execution and analysis to produce coverage statistics and a report of missing execution. The execution phase is handled by the coverage run command.

If you are missing the extension, first make sure you have the latest version of pip in use when installing coverage. If you are installing on Linux, you may need to install the python-dev and gcc support files …

Managing processes For coverage measurement to work properly, coverage has to be involved at the very beginning and very end of the Python process. There a number of ways to start processes and …

Coverage.py supports plugins that can change its behavior, to collect information from non-Python files, or to perform complex configuration. See Plug-in classes for details.

It is strongly recommended to use this extension: it is much faster, and is needed to support a number of coverage.py features. Most of the time, the C extension will be installed without any special action on …

Branch coverage extends the calculation to include the total number of possible branch exits, and the number of those taken. In this case the specific numbers shown in coverage reports don’t calculate …