Testing

The Go testing package supports creating unit test in go. Your test code is written in plain go, there is not a new assert language or syntax to learn. Write go code and use t.Fail or t.Error to signal the test did not pass.

To write a new test create a test file, ending in _test.go that includes functions with the following signature: func TestXxx(*testing.T)

Note: The function name must start with Test and include a capitalized second part to identify the test routing.

For example, if you want to test an Add function in your project:

Create add_test.go:

package main

import "testing"

func TestAdd(t *testing.T) {
    sum := Add(1, 1)
    if sum != 2 {
       t.Errorf("Expected %d => Received %d", 2, sum)
    }
}

Run test using: go test

Test Table

Use a table structure to setup and test multiple inputs and expected values.

func TestAdd(t *testing.T) {
    var testData = []struct {
        param1 int
        param2 int
        expect int
    }{
        { 1, 2, 3 },
        { 0, 1, 1 },
        { 1, 0, 1 },
        { -1, 1, 0 },
        { -1, -1, -2 },
    }

    for _, td := range testData {
        result := Add(td.param1, td.param2)
        if td.expect != result {
            t.Errorf("Expected %s but received %s", td.expect, result)
        }
    }
}