pytest-func-cov

Build	Release

Overview

This plugin attempts to provide a more meaningful test coverage metric for projects using pytest. The assumption is that, in reality, the proportion of lines of code covered by tests does not entirely reflect how much the tests explicitly cover. An additional indicator is how many functions, out of the total functions defined in a project, are explicitly invoked during tests. This way, a test which only calls a higher order function will not also count as testing the functions that it invokes during its execution, unlike traditional test coverage metrics.

pytest_func_cov provides an implementation of this metric, covering functions as well as methods, classmethods and staticmethods. A function is considered tested if it is invoked explicitly from a test function at least once. To make this check, the second stack frame is inspected when a discovered function is invoked.

Usage

pytest --func_cov=myproject tests/

Produces a report like:

--------------------pytest_func_cov-----------
Name                   Funcs   Miss     Cover
----------------------------------------------
myproject/module1.py       7      5       28% 
myproject/module2.py      10      3       70%
----------------------------------------------
TOTAL                     17      8       47%   

Similar to pytest-cov, you can use the --func_cov_report argument to configure the output. At the moment, the only supported option is term-missing, which adds another column to the output which lists all untested functions.

pytest --func_cov=myproject --func_cov_report=term-missing tests/

Produces a report like:

--------------------pytest_func_cov--------------------
Name                   Funcs   Miss     Cover   Missing
-------------------------------------------------------
myproject/module1.py       7      5       28%   func1, func2, MyClass.method, MyClass.static_method, MyClass.class_method
myproject/module2.py      10      3       70%   func3, func4, <lambda>
-------------------------------------------------------
TOTAL                     17      8       47%   

Configuration

A list of function name patterns to ignore can be specified in pytest.ini.

Example:

[pytest]
ignore_func_names = 
    ^test_*
    ^myfunction$

This will ignore all function names starting with "test_" and functions named "myfunction".