Implement tests for HasGravatar function

Makefile

@@ -0,0 +1,5 @@
+NOVENDOR_PATH = $$(glide novendor)
+
+runtest:
+	go clean
+	go test ${NOVENDOR_PATH}

glide.yaml

@@ -7,3 +7,6 @@ import:
   subpackages:
   - errgroup
   - syncmap
+testImport:
+- package: gopkg.in/check.v1
+- package: gopkg.in/h2non/gock.v1

verifier/gravatar_test.go

@@ -0,0 +1,63 @@
+package verifier
+
+import (
+	"errors"
+	"net/http"
+	"testing"
+
+	"gopkg.in/check.v1"
+	"gopkg.in/h2non/gock.v1"
+)
+
+type gravatarSuite struct{}
+
+var _ = check.Suite(&gravatarSuite{})
+
+func Test(t *testing.T) { check.TestingT(t) } // Just to make discoverable
+
+func configureRequestMock(addressMD5 string, statusCode int) *gock.Response {
+	url := "https://en.gravatar.com/" + addressMD5 + ".json"
+	return gock.New(url).
+		Head("").
+		Reply(statusCode)
+}
+
+func (s *gravatarSuite) TestHasGravatarStatusOk(c *check.C) {
+	address := &Address{
+		Username: "username",
+		Domain:   "domain.com",
+		Address:  "[email protected]",
+	}
+
+	configureRequestMock(address.MD5(), http.StatusOK)
+	defer gock.Off()
+
+	c.Assert(HasGravatar(address), check.Equals, true)
+}
+
+func (s *gravatarSuite) TestHasGravatarRequestError(c *check.C) {
+	address := &Address{
+		Username: "username",
+		Domain:   "domain.com",
+		Address:  "[email protected]",
+	}
+
+	gockResponse := configureRequestMock(address.MD5(), 200)
+	gockResponse.SetError(errors.New("Some error while requesting"))
+	defer gock.Off()
+
+	c.Assert(HasGravatar(address), check.Equals, false)
+}
+
+func (s *gravatarSuite) TestHasGravatarStatusNotOk(c *check.C) {
+	address := &Address{
+		Username: "username",
+		Domain:   "domain.com",
+		Address:  "[email protected]",
+	}
+
+	configureRequestMock(address.MD5(), http.StatusBadRequest)
+	defer gock.Off()
+
+	c.Assert(HasGravatar(address), check.Equals, false)
+}