Writing Basic Tests in Go

Snippet

Writing Basic Tests in Go

Go has built-in testing support through the testing package. Test files are named with _test.go suffix. Test functions start with Test prefix and receive a *testing.T argument. The t.Errorf() method marks a test as failed while allowing execution to continue. Use t.Run() for subtests to organize related test cases cleanly.

snippet.go
go
package main
 
import "testing"
 
func Add(a, b int) int {
    return a + b
}
 
func TestAdd(t *testing.T) {
    result := Add(2, 3)
    expected := 5
 
    if result != expected {
        t.Errorf("Add(2, 3) = %d, expected %d", result, expected)
    }
}
 
func TestAddNegative(t *testing.T) {
    result := Add(-5, 3)
    expected := -2
 
    if result != expected {
        t.Errorf("Add(-5, 3) = %d, expected %d", result, expected)
    }
}

Breakdown

func TestAdd(t *testing.T)

Test function receives testing.T parameter - t parameter controls test execution

t.Errorf("...", result, expected)

Errorf logs failure message without stopping test execution

t.Run("subtest name", func(t *testing.T) { })

Subtests using t.Run() group related test cases with descriptive names

testing.T

Testing.T type provides methods for logging and controlling test flow

Previous snippet Next snippet

From your library

Writing Basic Tests in Go

Related