TPI: test python branch coverage

[eleanorjboyd]

Refs: #24980

• macOS Johannes Rieken (@jrieken)
• linux Karthik Nadig (@karthiknadig)
• windows Aaron Munger (@amunger)

Complexity: 4

Author: Eleanor Boyd (@eleanorjboyd)

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✅ Test Plan: Verify Coverage Integration for Pytest & Unittest

📌 Objective

Ensure test branch coverage is correctly reported in VS Code using both pytest and unittest, and that the results align with the command-line coverage output (with minor rounding differences expected).

🧪 Repo & Project Info

Project Structure:

coverage-example-repo/
├── src/
│   └── math_utils.py
├── test/
│   ├── test_math_utils_pytest.py
│   └── test_math_utils_unittest.py
├── requirements.txt
└── README.md

🛠 Setup

Clone this repo: coverage-example-repo

git clone https://github.com/eleanorjboyd/coverage-example-repo
cd coverage-example-repo

In VS Code, open the Command Palette → Python: Create Environment

If the UI does not prompt to install requirements, run:

pip install -r requirements.txt

✅ Part 1: Test with Pytest

• Open the Testing tab in VS Code
• Select pytest as the test framework
• Click the 3rd run button (▶️ with checkmark) to run tests with coverage
• Coverage results are visible
• Branch coverage is shown
• Coverage numbers look reasonable

✅ Part 2: Test with Unittest

• Change the test framework to unittest (settings.json or VS Code UI)
• Update any necessary args in python.testing.unittestArgs
• Click the same 3rd run button to run tests with coverage
• Confirm:
  • Coverage results are visible
  • Branch coverage is shown
  • Coverage numbers make sense and are comparable to pytest

✅ Part 3: Cross-check with CLI Coverage

• Run tests with pytest from the CLI:

coverage run --branch -m pytest
coverage report

Erase and re-run with unittest:

coverage erase
coverage run --branch -m unittest discover -s test
coverage report

Confirm:

• CLI coverage output branch coverage is the same as the output from the UI
  ⚠️ Note: minor rounding differences are expected