Add Sort and Direction to PullRequestListOptions

As per https://developer.github.com/v3/pulls/#list-pull-requests

github/pulls.go

@@ -75,6 +75,15 @@ type PullRequestListOptions struct {
 	// Base filters pull requests by base branch name.
 	Base string `url:"base,omitempty"`
 
+	// Sort specifies how to sort pull requests. Possible values are: created,
+	// updated, popularity, long-running. Default is "created".
+	Sort string `url:"sort,omitempty"`
+
+	// Direction in which to sort pull requests. Possible values are: asc, desc.
+	// If Sort is "created" or not specified, Default is "desc", otherwise Default
+	// is "asc"
+	Direction string `url:"direction,omitempty"`
+
 	ListOptions
 }
 

github/pulls_test.go

@@ -20,15 +20,17 @@ func TestPullRequestsService_List(t *testing.T) {
 	mux.HandleFunc("/repos/o/r/pulls", func(w http.ResponseWriter, r *http.Request) {
 		testMethod(t, r, "GET")
 		testFormValues(t, r, values{
-			"state": "closed",
-			"head":  "h",
-			"base":  "b",
-			"page":  "2",
+			"state":     "closed",
+			"head":      "h",
+			"base":      "b",
+			"sort":      "created",
+			"direction": "desc",
+			"page":      "2",
 		})
 		fmt.Fprint(w, `[{"number":1}]`)
 	})
 
-	opt := &PullRequestListOptions{"closed", "h", "b", ListOptions{Page: 2}}
+	opt := &PullRequestListOptions{"closed", "h", "b", "created", "desc", ListOptions{Page: 2}}
 	pulls, _, err := client.PullRequests.List("o", "r", opt)
 
 	if err != nil {