Calculator Test Lab

A calculator.go file provides four functions. Your job is to write comprehensive table-driven tests for all of them.

The calculator functions

What to implement

Write table-driven tests for all four functions:

1. TestAdd — at least 3 cases: two positives, two negatives, zero identity
2. TestSub — at least 3 cases: basic subtraction, negative result, subtracting zero
3. TestMul — at least 3 cases: positive, negative, multiply by zero
4. TestDiv — at least 3 cases including the error case when b == 0

Each test must:

• Use a slice of struct test cases
• Check the returned value
• For TestDiv, check both the float result and whether an error is returned for b == 0

Simulating go test in the Playground

Since the Go Playground doesn't run go test, call each test function manually from main using a *testing.T{}: