Add test for GitHub remote Authorize()

To test that it correctly authorises a valid user, prior to me extending it.
This only tests the happy path because simulating oAuth failures is going
to be quite hard at this stage.

plugin/remote/github/github_test.go

@@ -1,6 +1,9 @@
 package github
 
 import (
+	"fmt"
+	"net/http"
+	"net/http/httptest"
 	"testing"
 
 	"github.com/drone/drone/plugin/remote/github/testdata"
@@ -90,5 +93,20 @@ func Test_Github(t *testing.T) {
 		g.It("Should parse a commit hook")
 
 		g.It("Should parse a pull request hook")
+
+		g.It("Should authorize a valid user", func() {
+			var resp = httptest.NewRecorder()
+			var state = "validstate"
+			var req, _ = http.NewRequest(
+				"GET",
+				fmt.Sprintf("%s/?code=sekret&state=%s", server.URL, state),
+				nil,
+			)
+			req.AddCookie(&http.Cookie{Name: "github_state", Value: state})
+
+			var login, err = github.Authorize(resp, req)
+			g.Assert(err == nil).IsTrue()
+			g.Assert(login == nil).IsFalse()
+		})
 	})
 }

plugin/remote/github/testdata/testdata.go

@@ -15,6 +15,15 @@ func NewServer() *httptest.Server {
 
 		// evaluate the path to serve a dummy data file
 		switch r.URL.Path {
+		case "/login/oauth/access_token":
+			w.Write(accessTokenPayload)
+			return
+		case "/user":
+			w.Write(userPayload)
+			return
+		case "/user/emails":
+			w.Write(userEmailsPayload)
+			return
 		case "/user/repos":
 			w.Write(userReposPayload)
 			return
@@ -56,6 +65,64 @@ func NewServer() *httptest.Server {
 	return server
 }
 
+var accessTokenPayload = []byte(`access_token=sekret&scope=repo%2Cuser%3Aemail&token_type=bearer`)
+
+var userPayload = []byte(`
+{
+  "login": "octocat",
+  "id": 1,
+  "avatar_url": "https://github.com/images/error/octocat_happy.gif",
+  "gravatar_id": "",
+  "url": "https://api.github.com/users/octocat",
+  "html_url": "https://github.com/octocat",
+  "followers_url": "https://api.github.com/users/octocat/followers",
+  "following_url": "https://api.github.com/users/octocat/following{/other_user}",
+  "gists_url": "https://api.github.com/users/octocat/gists{/gist_id}",
+  "starred_url": "https://api.github.com/users/octocat/starred{/owner}{/repo}",
+  "subscriptions_url": "https://api.github.com/users/octocat/subscriptions",
+  "organizations_url": "https://api.github.com/users/octocat/orgs",
+  "repos_url": "https://api.github.com/users/octocat/repos",
+  "events_url": "https://api.github.com/users/octocat/events{/privacy}",
+  "received_events_url": "https://api.github.com/users/octocat/received_events",
+  "type": "User",
+  "site_admin": false,
+  "name": "monalisa octocat",
+  "company": "GitHub",
+  "blog": "https://github.com/blog",
+  "location": "San Francisco",
+  "email": "octocat@github.com",
+  "hireable": false,
+  "bio": "There once was...",
+  "public_repos": 2,
+  "public_gists": 1,
+  "followers": 20,
+  "following": 0,
+  "created_at": "2008-01-14T04:33:35Z",
+  "updated_at": "2008-01-14T04:33:35Z",
+  "total_private_repos": 100,
+  "owned_private_repos": 100,
+  "private_gists": 81,
+  "disk_usage": 10000,
+  "collaborators": 8,
+  "plan": {
+    "name": "Medium",
+    "space": 400,
+    "private_repos": 20,
+    "collaborators": 0
+  }
+}
+`)
+
+var userEmailsPayload = []byte(`
+[
+  {
+    "email": "octocat@github.com",
+    "verified": true,
+    "primary": true
+  }
+]
+`)
+
 // sample repository list
 var userReposPayload = []byte(`
 [