Unit Test Generator

Discovery

Before writing a single test, extract the full contract of the target code:

• Inputs — types, optionality, valid ranges, format constraints
• Outputs — return type, shape, nullability; does it mutate args or external state?
• Dependencies — what does it call that needs mocking? (DB, fetch, logger, Date, Math.random)
• Implicit assumptions — things the function expects to be true but doesn't validate (e.g. "caller always passes a non-empty array")
• Branching logic — every if, ternary, ||, &&, and ?? is a branch that needs at least one test each side

Test Case Taxonomy

Map the function's contract to these four layers before writing: