A translation service can pass its normal checks and still fail when a language is unsupported, input contains unusual characters, or values are unexpectedly large or small. An edge case is a rare or extreme condition that exposes behavior you did not expect. section 3.3
Treat edge cases as test scenarios rather than distant speculation. Add a failing test, implement the smallest behavior that satisfies it, and keep the cycle moving without leaping into over-design. section 3.3
Unsupported translations and messy input
A translator returns an empty string for an unknown language or word. Table tests then add cases such as Dutch, “bye,” uppercase values, and trailing spaces; input sanitization normalizes case and whitespace before translation.
