Detailed use of the Python COVERAGE module

The COVERAGE module in Python is a tool to measure code coverage.It can track and report which parts in the code are executed and which parts have not been executed.By using the COVERAGE module, developers can obtain detailed information about the code coverage of the test case to help discover vulnerabilities and problems in the code. To use the COVERAGE module, first of all, you need to install the COVERAGE software package in the Python environment.You can use the PIP command to install it: pip install coverage After the installation is completed, you can import the Coverage module in the code: python import coverage Next, you need to pack the code to be tested in the Coverage module.You can use the `with` statement to implement this: python with coverage.Coverage() as cov: # Here to write code that needs to be tested In the `With` statement block, any executed sentence will be tracked by the COVERAGE module.You can place the `with` statement in the test function or test case to measure the code coverage of its execution. After performing the test code, you can use the various methods provided by the COVERAGE module to obtain the detailed information of the code coverage.Here are some commonly used examples: -` Cov.start () `: Start the COVERAGE module and start tracking code coverage. -` Cov.stop () `: Stop the tracking of the COVERAGE module. -` Cov.save () `: Save the tracking result into the file. -` Cov.report () `: Generates the code coverage of human readable code. -` cov.html_report () `: The code coverage report in HTML format. -Pv.annotate () `: merge the source code and coverage information into a file. In addition, the COVERAGE module also provides other methods, such as `get_lines ()` and `get_data ()` to obtain more detailed coverage data. After running the test code and obtaining the coverage data, you can use the report function provided by the COVERAGE module to view the code coverage.These reports can be generated in text, HTML and other formats.For example, the following code can be used to generate a report in HTML format: python cov.html_report(directory='coverage_report') The above code will generate a directory called `Coverage_report`, which contains the code coverage report in HTML format. To sum up, using the COVERAGE module can easily measure the coverage of Python code.Through tracking and reporting which codes are executed and which code is not executed, developers can better understand the degree of coverage of their test cases, and can be optimized and improved as needed.