Add support for Enterprise GetRunner (google#3185)

Fixes: google#3182.

Author: matt-simons

github/enterprise_actions_runners.go

@@ -101,6 +101,27 @@ func (s *EnterpriseService) ListRunners(ctx context.Context, enterprise string,
 	return runners, resp, nil
 }
 
+// GetRunner gets a specific self-hosted runner configured in an enterprise.
+//
+// GitHub API docs: https://docs.github.com/enterprise-cloud@latest/rest/actions/self-hosted-runners#get-a-self-hosted-runner-for-an-enterprise
+//
+//meta:operation GET /enterprises/{enterprise}/actions/runners/{runner_id}
+func (s *EnterpriseService) GetRunner(ctx context.Context, enterprise string, runnerID int64) (*Runner, *Response, error) {
+	u := fmt.Sprintf("enterprises/%v/actions/runners/%v", enterprise, runnerID)
+	req, err := s.client.NewRequest("GET", u, nil)
+	if err != nil {
+		return nil, nil, err
+	}
+
+	runner := new(Runner)
+	resp, err := s.client.Do(ctx, req, runner)
+	if err != nil {
+		return nil, resp, err
+	}
+
+	return runner, resp, nil
+}
+
 // RemoveRunner forces the removal of a self-hosted runner from an enterprise using the runner id.
 //
 // GitHub API docs: https://docs.github.com/enterprise-cloud@latest/rest/actions/self-hosted-runners#delete-a-self-hosted-runner-from-an-enterprise

github/enterprise_actions_runners_test.go

@@ -145,6 +145,46 @@ func TestEnterpriseService_ListRunners(t *testing.T) {
 	})
 }
 
+func TestEnterpriseService_GetRunner(t *testing.T) {
+	client, mux, _, teardown := setup()
+	defer teardown()
+
+	mux.HandleFunc("/enterprises/e/actions/runners/23", func(w http.ResponseWriter, r *http.Request) {
+		testMethod(t, r, "GET")
+		fmt.Fprint(w, `{"id":23,"name":"MBP","os":"macos","status":"online"}`)
+	})
+
+	ctx := context.Background()
+	runner, _, err := client.Enterprise.GetRunner(ctx, "e", 23)
+	if err != nil {
+		t.Errorf("Enterprise.GetRunner returned error: %v", err)
+	}
+
+	want := &Runner{
+		ID:     Int64(23),
+		Name:   String("MBP"),
+		OS:     String("macos"),
+		Status: String("online"),
+	}
+	if !cmp.Equal(runner, want) {
+		t.Errorf("Enterprise.GetRunner returned %+v, want %+v", runner, want)
+	}
+
+	const methodName = "GetRunner"
+	testBadOptions(t, methodName, func() (err error) {
+		_, _, err = client.Enterprise.GetRunner(ctx, "\n", 23)
+		return err
+	})
+
+	testNewRequestAndDoFailure(t, methodName, client, func() (*Response, error) {
+		got, resp, err := client.Enterprise.GetRunner(ctx, "e", 23)
+		if got != nil {
+			t.Errorf("testNewRequestAndDoFailure %v = %#v, want nil", methodName, got)
+		}
+		return resp, err
+	})
+}
+
 func TestEnterpriseService_RemoveRunner(t *testing.T) {
 	client, mux, _, teardown := setup()
 	defer teardown()