diff --git a/gh_test.go b/gh_test.go
index 39574a9..1af2d7e 100644
--- a/gh_test.go
+++ b/gh_test.go
@@ -5,6 +5,8 @@ import (
 	"os"
 	"testing"
 
+	"github.com/cli/go-gh/internal/httpmock"
+	"github.com/cli/go-gh/pkg/api"
 	"github.com/stretchr/testify/assert"
 )
 
@@ -42,3 +44,87 @@ func TestRunError(t *testing.T) {
 	assert.Equal(t, "", stdOut.String())
 	assert.Equal(t, "process exited with error", stdErr.String())
 }
+
+func TestRESTClient(t *testing.T) {
+	tempDir := t.TempDir()
+	orig_GH_CONFIG_DIR := os.Getenv("GH_CONFIG_DIR")
+	orig_GH_TOKEN := os.Getenv("GH_TOKEN")
+	t.Cleanup(func() {
+		os.Setenv("GH_CONFIG_DIR", orig_GH_CONFIG_DIR)
+		os.Setenv("GH_TOKEN", orig_GH_TOKEN)
+	})
+	os.Setenv("GH_CONFIG_DIR", tempDir)
+	os.Setenv("GH_TOKEN", "GH_TOKEN")
+
+	http := httpmock.NewRegistry(t)
+	http.Register(
+		httpmock.REST("GET", "some/test/path"),
+		httpmock.StatusStringResponse(200, `{"message": "success"}`),
+	)
+
+	client, err := RESTClient(&api.ClientOptions{Transport: http})
+	assert.NoError(t, err)
+
+	res := struct{ Message string }{}
+	err = client.Do("GET", "some/test/path", nil, &res)
+	assert.NoError(t, err)
+	assert.Equal(t, "success", res.Message)
+	assert.Equal(t, "api.github.com", http.Requests[0].URL.Hostname())
+	assert.Equal(t, "token GH_TOKEN", http.Requests[0].Header.Get("Authorization"))
+}
+
+func TestGQLClient(t *testing.T) {
+	tempDir := t.TempDir()
+	orig_GH_CONFIG_DIR := os.Getenv("GH_CONFIG_DIR")
+	orig_GH_TOKEN := os.Getenv("GH_TOKEN")
+	t.Cleanup(func() {
+		os.Setenv("GH_CONFIG_DIR", orig_GH_CONFIG_DIR)
+		os.Setenv("GH_TOKEN", orig_GH_TOKEN)
+	})
+	os.Setenv("GH_CONFIG_DIR", tempDir)
+	os.Setenv("GH_TOKEN", "GH_TOKEN")
+
+	http := httpmock.NewRegistry(t)
+	http.Register(
+		httpmock.GQL("QUERY"),
+		httpmock.StringResponse(`{"data":{"viewer":{"login":"hubot"}}}`),
+	)
+
+	client, err := GQLClient(&api.ClientOptions{Transport: http})
+	assert.NoError(t, err)
+
+	vars := map[string]interface{}{"var": "test"}
+	res := struct{ Viewer struct{ Login string } }{}
+	err = client.Do("QUERY", vars, &res)
+	assert.NoError(t, err)
+	assert.Equal(t, "hubot", res.Viewer.Login)
+	assert.Equal(t, "api.github.com", http.Requests[0].URL.Hostname())
+	assert.Equal(t, "token GH_TOKEN", http.Requests[0].Header.Get("Authorization"))
+}
+
+func TestHTTPClient(t *testing.T) {
+	tempDir := t.TempDir()
+	orig_GH_CONFIG_DIR := os.Getenv("GH_CONFIG_DIR")
+	orig_GH_TOKEN := os.Getenv("GH_TOKEN")
+	t.Cleanup(func() {
+		os.Setenv("GH_CONFIG_DIR", orig_GH_CONFIG_DIR)
+		os.Setenv("GH_TOKEN", orig_GH_TOKEN)
+	})
+	os.Setenv("GH_CONFIG_DIR", tempDir)
+	os.Setenv("GH_TOKEN", "GH_TOKEN")
+
+	http := httpmock.NewRegistry(t)
+	http.Register(
+		httpmock.REST("GET", "some/test/path"),
+		httpmock.StatusStringResponse(200, `{"message": "success"}`),
+	)
+
+	client, err := HTTPClient(&api.ClientOptions{Transport: http})
+	assert.NoError(t, err)
+
+	res, err := client.Get("https://api.github.com/some/test/path")
+	assert.NoError(t, err)
+	assert.Equal(t, 200, res.StatusCode)
+	assert.Equal(t, "api.github.com", http.Requests[0].URL.Hostname())
+	assert.Equal(t, "token GH_TOKEN", http.Requests[0].Header.Get("Authorization"))
+}