Testing

Bastante interesante la forma de manejar los tests con el slice de structs

• Testing

  Go has a builtin testing library, which is awesome!

  How To:

  To define a test must:

  1. Create a the test file named <file>_test.go, where <file> is the name of the file you are testing
  2. Write the tests
  3. Run the tests with go test

  Example:

  main.go:

  package main
  
  func Sum(x, y int) int {
  	return x + y
  }
  

main_test.go:

package main

import (
	"fmt"
	"testing"
)

func TestSum(t *testing.T) {
	fmt.Println()
	total := Sum(5, 5)

	if total != 10 {
		t.Errorf("Wrong output, expected 10, go %d", total)
	}
}

Often times it’s useful to test various cases in single test. To do that you’d wanna use a slice and iterate over them like so:

tableCases := []struct {
	a int
	b int
	n int
}{
	{1, 2, 3},
	{2, 2, 4},
	{25, 26, 51},
}

for _, item := range tableCases {
	total := Sum(item.a, item.b)
	if total != item.n {
		t.Errorf("Failed: Incorrect sum, got %d expected %d", total, item.n)
	}
}

main_test

package main

import "testing"

func TestSum(t *testing.T) {
	tables := []struct {
		x int
		y int
		r int
	}{
		{1, 2, 3},
		{2, 2, 4},
		{3, 2, 5},
		{25, 26, 51},
	}

	for _, table := range tables {
		total := Sum(table.x, table.y)
		if total != table.r {
			t.Errorf("Sum(%d, %d) was incorrect, got: %d, want: %d.", table.x, table.y, total, table.r)
		}
	}
}

main

package main

func Sum(x, y int) int {
	return x + y
}

func GetMax(x, y int) int {
	if x > y {
		return x
	}
	return y
}

Para programar los tests os recomiendo utilizar el módulo https://github.com/stretchr/testify, ya que te ofrece diversas funcionalidades que facilitan la vida a la hora de programar los tests de Go.

Yo encuentro especialmente útil el paquete assert, el qual te permite hacer los asserts igual que en cualquier lenguaje de programación. Por ejempo:

assert.Equal(t, 63997.93, newImport)

main.go

package main

import (
	"fmt"
	"strings"
)

func Sum(x, y int) int {
	return x + y
}

func SayHello(name string) string {
	return fmt.Sprintf("Hello %v", strings.Title(strings.ToLower(name)))
}

func GreaterThan(x, y int) int {
	if x > y {
		return x
	}
	return y
}

func SumTotal(numbers ...int) int {
	total := 0
	for _, val := range numbers {
		total += val
	}
	return total
}

main_test.go

package main

import (
	"testing"
)

func TestSum(t *testing.T) {
	type args struct {
		x int
		y int
	}
	tests := []struct {
		name string
		args args
		want int
	}{
		// TODO: Add test cases.
		{name: "Test Sum Correct", args: args{x: 6, y: 6}, want: 12},
		{name: "Test Sum Correct", args: args{x: 5, y: 5}, want: 10},
	}
	for _, tt := range tests {
		t.Run(tt.name, func(t *testing.T) {
			if got := Sum(tt.args.x, tt.args.y); got != tt.want {
				t.Errorf("Sum() = %v, want %v", got, tt.want)
			}
		})
	}
}

func TestSayHello(t *testing.T) {
	type args struct {
		name string
	}
	tests := []struct {
		name string
		args args
		want string
	}{
		// TODO: Add test cases.
		{name: "Correctly", args: args{name: "pedro"}, want: "Hello Pedro"},
		{name: "Correctly", args: args{name: "Ramon"}, want: "Hello Ramon"},
		{name: "Correctly", args: args{name: "mARIa"}, want: "Hello Maria"},
		{name: "Correctly", args: args{name: "DIANA"}, want: "Hello Diana"},
	}
	for _, tt := range tests {
		t.Run(tt.name, func(t *testing.T) {
			if got := SayHello(tt.args.name); got != tt.want {
				t.Errorf("SayHello() = %v, want %v", got, tt.want)
			}
		})
	}
}

func TestGreaterThan(t *testing.T) {
	type args struct {
		x int
		y int
	}
	tests := []struct {
		name string
		args args
		want int
	}{
		// TODO: Add test cases.
		{name: "Equal", args: args{x: 6, y: 6}, want: 6},
		{name: "X greater", args: args{x: 9, y: 8}, want: 9},
		{name: "Y greater", args: args{x: 1, y: 99}, want: 99},
	}
	for _, tt := range tests {
		t.Run(tt.name, func(t *testing.T) {
			if got := GreaterThan(tt.args.x, tt.args.y); got != tt.want {
				t.Errorf("GreaterThan() = %v, want %v", got, tt.want)
			}
		})
	}
}

func TestSumTotal(t *testing.T) {
	type args struct {
		numbers []int
	}
	tests := []struct {
		name string
		args args
		want int
	}{
		// TODO: Add test cases.
		{name: "Correctly", args: args{[]int{1, 3, 2}}, want: 6},
		{name: "Correctly", args: args{[]int{106, 105, 6}}, want: 217},
		{name: "Correctly", args: args{[]int{96, 3, 0}}, want: 99},
	}
	for _, tt := range tests {
		t.Run(tt.name, func(t *testing.T) {
			if got := SumTotal(tt.args.numbers...); got != tt.want {
				t.Errorf("SumTotal() = %v, want %v", got, tt.want)
			}
		})
	}
}

El curso la verdad es excelente, super bien explicado y las testing y es la parte fundamental de un codigo de alta calidad

Interesante

Para correr los test en paralelo.

package main

import "testing"

// func TestSum(t *testing.T) {
// 	total := Sum(5, 5)
// 	if total != 10 {
// 		t.Error("Suma was incorrect, got ", total, "expected ", 10)
// 	}
// }

func TestSum(t *testing.T) {
	t.Parallel()
	testCases := []struct {
		desc    string
		a, b, n int
	}{
		{
			desc: "Tetsing 1+2 = 3",
			a:    1, b: 2, n: 3,
		},
		{
			desc: "Tetsing 2+2 = 4",
			a:    2, b: 2, n: 4,
		},
		{
			desc: "Tetsing 25+26 = 51",
			a:    25, b: 26, n: 51,
		},
	}
	for _, tC := range testCases {
		tC := tC
		t.Run(tC.desc, func(t *testing.T) {
			t.Parallel()
			total := Sum(tC.a, tC.b)
			if total != tC.n {
				t.Error("Sum was incorrect, got", total, "expected", tC.n)
			}
		})
	}
}