moq

To install the latest released version of Moq, use the go install command. Note that Go 1.18+ is required for installing from source. For older Go versions, use the pre-built binaries from the official Moq releases page.

$ go install github.com/matryer/moq@latest

To release a new version, you must first tag the repository and push the tag to origin, then run GoReleaser with a valid GITHUB_TOKEN.

1. Tag the repository:

git tag -a v0.1.0 -m "release tag."
git push origin v0.1.0

2. Run GoReleaser:

GITHUB_TOKEN=xxx goreleaser --clean

#!/bin/bash
git tag -a v0.1.0 -m "release tag."
git push origin v0.1.0
GITHUB_TOKEN=xxx goreleaser --clean

Moq uses GoReleaser to manage its release builds. To prepare for releasing, you must install GoReleaser and configure your GitHub credentials.

1. Install GoReleaser via Homebrew:

brew install goreleaser/tap/goreleaser

2. Create a New personal access token on GitHub and export it as the GITHUB_TOKEN environment variable.

You can automate mock generation by adding a //go:generate directive directly above your interface definition in your Go source files. This allows you to run go generate ./... to refresh your mocks.

package my

//go:generate moq -out myinterface_moq_test.go . MyInterface

type MyInterface interface {
	Method1() error
	Method2(i int)
}

If you are modifying the GoReleaser configuration and want to verify the changes without actually publishing anything, use the --snapshot and --skip=publish flags.

goreleaser --snapshot --skip=publish --clean

Moq creates a struct where each interface method is represented by a function field. In your tests, you assign a function to these fields to define the mock's behavior. You can use captured variables from the test scope to verify interactions.

func TestCompleteSignup(t *testing.T) { 
	var sentTo string

	// Initialize the mock with custom behavior
	mockedEmailSender = &EmailSenderMock{
		SendFunc: func(to, subject, body string) error {
			sentTo = to
			return nil
		},
	}

	CompleteSignUp("me@email.com", mockedEmailSender)

	// Verify behavior using call tracking
	callsToSend := len(mockedEmailSender.SendCalls())
	if callsToSend != 1 {
		t.Errorf("Send was called %d times", callsToSend)
	}
	if sentTo != "me@email.com" {
		t.Errorf("unexpected recipient: %s", sentTo)
	}
}

Available flags for the moq command:

The moq command generates mock implementations for Go interfaces. The basic syntax requires a source directory and one or more interfaces. You can also specify an alias for a mock using the interface:alias format.

Usage: moq [flags] source-dir interface [interface2 [interface3 [...]]]

Example: To generate a mock named MyMock for an interface named MyInterface in the current directory and save it to a specific package:

moq -pkg different . MyInterface:MyMock