Test Function Has Wrong Signature

Why This Happens

Go's testing framework discovers tests by function name and signature. A function named TestXxx must accept exactly *testing.T as its sole parameter and return no values. If the signature is wrong, the test runner ignores it or reports an error.

The Problem

func TestAdd(a, b int) int { // wrong signature
    return a + b
}

The Fix

func TestAdd(t *testing.T) {
    result := Add(2, 3)
    if result != 5 {
        t.Errorf("Add(2, 3) = %d, want 5", result)
    }
}

Step-by-Step Fix

1. 1

   Identify the wrong signature

   Find test functions that do not match the func TestXxx(t *testing.T) signature.

2. 2

   Fix the signature

   Change the function to accept *testing.T as the only parameter and return nothing.

3. 3

   Move test logic inside

   Use t.Errorf, t.Fatal, or t.Run for assertions and sub-tests.