Table-driven tests are the idiomatic Go testing pattern for writing comprehensive test suites with minimal code duplication. The pattern involves defining a slice of test cases as struct instances, where each struct contains input values and expected outputs. The test then iterates through the table, running each test case with t.Run for organized subtest execution.
This approach makes it easy to add new test cases by simply adding another struct instance to the table. The subtests generated by t.Run provide clear, organized output showing which specific test cases pass or fail. This is especially valuable for edge cases, boundary conditions, and different input scenarios.
The pattern also makes it easier to maintain tests when function signatures change. You update the test table structure once, and all test cases automatically adapt. This reduces boilerplate and makes your test code more maintainable and scalable.