Mockgen: Mock generation in Go

Mockgen is an utility for testify which generates the mundane mock initialisation code such as:

• mock classes of all services of a struct;
• type-safe setup methods (On("FunctionName") and Return());
• AssertExpectations for all services of a struct.

Installing

Install the CLI for code generation

go get github.com/MyNihongo/mockgen/cmd/mockgen

Add go generate for required mocks

//go:generate mockgen impl1:Impl1Service
package mocking

import (
	"github.com/MyNihongo/mockgen/mocking/pkg1"
	"github.com/MyNihongo/mockgen/mocking/pkg2"
)

type impl1 struct {
	ser1 pkg1.Service1_1
	ser2 pkg2.Service2_1
}

type Impl1Service interface {
	Foo()
}

func (i *impl1) Foo() {
	i.ser1.Foo("string", 12)
	i.ser2.Foo("string1", "string2")
}

This will generate quite a lot of code, so please go to mock_gen_test.go to see what is actually generated.

Command samples

Unlimited number of services can be passed for generation.
A single entry may be structType or structType:interfaceType.

mockgen service1:Service1 service2:Service2 service3:Service3

Generate mocks for service1, service2 and service3 with interfaces.

mockgen service1:Service1 service2

Generate a mock for service1 with its interface; Generate a mock for service2 without an interface.

Keep the package reference

Command go mod tidy will remove the reference of Mockgen by default. In order to keep the reference create a dummy file somewhere and import a dummy type.

package pkg

import "github.com/MyNihongo/mockgen"

var _ mockgen.Reference