[michalmaj]

Summary

Expand the example test suite with whitespace edge cases and use the change to teach focused pytest parametrization.

Why

The text utilities already handle whitespace-only and leading or trailing whitespace, but the test suite did not document those behaviors. The existing repeated tests also provide a small, practical example of when parametrization improves readability.

Changes

• parametrize related normalization and word-counting inputs
• add whitespace-only and leading or trailing whitespace cases
• explain pytest parametrization and when separate tests are clearer
• record the completed testing milestone in the roadmap

Type of change

Select the most relevant option.

• Documentation
• Project configuration
• New feature
• Tests
• CI/CD
• Refactoring
• Bug fix

Checklist

• The change is small and focused
• The pull request title is clear
• I updated documentation if needed
• I added or updated tests if needed
• I ran local checks if applicable

Notes

The suite now collects 12 tests instead of 8. No package behavior changed.

Local checks passed:

• uv run ruff check .
• uv run ruff format --check .
• uv run pytest
• uv build --no-sources
• git diff --check