#GMock A mocking utility for Go.

This was created with unit testing in mind, to make it easier to isolate components.

Compatibility verified with Go 1.4 and up.

##Installation

Just use go get

  go get github.com/cfmobile/gmock

##Usage

Import the header

import (
  //...
  "github.com/cfmobile/gmock"
)

Use GMock to mock your variables with another value of the same type.

1. Call one of the available constructors with a pointer to the variable you'd like to mock. Retain the *GMock object returned.
2. Assign a mock value of the same type (if you haven't done so in the constructor) by passing it to the Replace(_) method in the *GMock object you retained.
3. Once you're done using your mocked value, restore the original value by calling Restore() in the *GMock object.

Important: If you don't call Restore() and the GMock object is destroyed, you won't be able to restore the original value to your variable.

####Example 1: Using the constructor CreateMockWithTarget(_)

The default constructor doesn't change the value until Replace(_) is called.

package main
import (
  "fmt"
  "github.com/cfmobile/gmock"
)

func main() {
  var someVariable = "my original value"

  fmt.Println("1:", someVariable)

  mock := gmock.CreateMockWithTarget(&someVariable)

  fmt.Println("2:", someVariable)

  mock.Replace("mocked value")

  fmt.Println("3:", someVariable)

  mock.Restore()

  fmt.Println("4:", someVariable)
}

Should print:

1: my original value
2: my original value
3: mocked value
4: my original value

####Example 2: Using the constructor MockTargetWithValue(_, _)

The target variable is immediately mocked with the value specified in the second parameter

package main
import (
  "fmt"
  "github.com/cfmobile/gmock"
)

func main() {
  var someVariable = "my original value"

  fmt.Println("1:", someVariable)

  mock := gmock.MockTargetWithValue(&someVariable, "mocked value")

  fmt.Println("2:", someVariable)

  mock.Restore()

  fmt.Println("3:", someVariable)
}

Should print:

1: my original value
2: mocked value
3: my original value

####Example 3: Multiple calls to Replace(_)

Calling Replace(_) multiple times won't make GMock lose track of the original value.

package main
import (
  "fmt"
  "github.com/cfmobile/gmock"
)

func main() {
  var someVariable = "my original value"

  fmt.Println("1:", someVariable)

  mock := gmock.MockTargetWithValue(&someVariable, "mocked value")

  fmt.Println("2:", someVariable)

  mock.Replace("another mock value")

  fmt.Println("3:", someVariable)

  mock.Restore()

  fmt.Println("4:", someVariable)
}

Should print:

1: my original value
2: mocked value
3: another mock value
4: my original value