✨ Initial Commit

.gitignore

@@ -0,0 +1 @@
+coverage

app/Application.go

@@ -0,0 +1,7 @@
+package app
+
+import "pjm.dev/mock/calculator"
+
+type Application struct {
+	Calculator calculator.Calculatorer
+}

app/CoolAlgorithm.go

@@ -0,0 +1,12 @@
+package app
+
+func (application *Application) CoolAlgorithm(x int) int {
+	var output int = x
+
+	output = application.Calculator.Add(output, 0)
+	output = application.Calculator.Subtract(output, 0)
+	output = application.Calculator.Multiply(output, 1)
+	output = application.Calculator.Divide(output, 1)
+
+	return output
+}

app/CoolAlgorithm_test.go

@@ -0,0 +1,45 @@
+package app_test
+
+import (
+	"testing"
+
+	"go.uber.org/mock/gomock"
+	"pjm.dev/mock/app"
+	"pjm.dev/mock/mock_calculator"
+)
+
+func TestCoolAlgorithm(t *testing.T) {
+	ctrl := gomock.NewController(t)
+	mockCalculator := mock_calculator.NewMockCalculatorer(ctrl)
+
+	number := 100
+
+	mockCalculator.
+		EXPECT().
+		Add(number, 0).
+		Times(1).
+		Return(number)
+
+	mockCalculator.
+		EXPECT().
+		Subtract(number, 0).
+		Times(1).
+		Return(number)
+
+	mockCalculator.
+		EXPECT().
+		Multiply(number, 1).
+		Times(1).
+		Return(number)
+
+	mockCalculator.
+		EXPECT().
+		Divide(number, 1).
+		Times(1).
+		Return(number)
+
+	application := app.Application{Calculator: mockCalculator}
+	if application.CoolAlgorithm(number) != number {
+		t.Fail()
+	}
+}

calculator/Calculatorer.go

@@ -0,0 +1,8 @@
+package calculator
+
+type Calculatorer interface {
+	Add(int, int) int
+	Subtract(int, int) int
+	Multiply(int, int) int
+	Divide(int, int) int
+}

calculator/Client.go

@@ -0,0 +1,19 @@
+package calculator
+
+type Client struct{}
+
+func (client *Client) Add(a int32, b int32) int32 {
+	panic("Can't call this in unit tests!")
+}
+
+func (client *Client) Subtract(a int32, b int32) int32 {
+	panic("Can't call this in unit tests!")
+}
+
+func (client *Client) Multiply(a int32, b int32) int32 {
+	panic("Can't call this in unit tests!")
+}
+
+func (client *Client) Divide(a int32, b int32) int32 {
+	panic("Can't call this in unit tests!")
+}

go.mod

@@ -0,0 +1,5 @@
+module pjm.dev/mock
+
+go 1.21.1
+
+require go.uber.org/mock v0.3.0

go.sum

@@ -0,0 +1,2 @@
+go.uber.org/mock v0.3.0 h1:3mUxI1No2/60yUYax92Pt8eNOEecx2D3lcXZh2NEZJo=
+go.uber.org/mock v0.3.0/go.mod h1:a6FSlNadKUHUa9IP5Vyt1zh4fC7uAwxMutEAscFbkZc=