Use statusCheckRollup internal GraphQL to simplify Statuses+Checks

With the old approach, we had to enumerate all StatusContexts and
CheckRuns to calculate whether a PR has passing or failing CI status.

Using `statusCheckRollup` which is behind the `pe_mobile` feature flag,
this is somewhat simpler because both StatusContexts and CheckRuns are
now behind the same connection.

Additionally, should we decide to *not* show the number of
passing/failing checks, this now approach allows us to consume the
`statusCheckRollup { state }` field and avoid paginated collections
and calculating the "winning" state altogether.

api/queries.go

@@ -35,17 +35,11 @@ type PullRequest struct {
 	Commits struct {
 		Nodes []struct {
 			Commit struct {
-				Status struct {
-					Contexts []struct {
-						State string
-					}
-				}
-				CheckSuites struct {
-					Nodes []struct {
-						CheckRuns struct {
-							Nodes []struct {
-								Conclusion string
-							}
+				StatusCheckRollup struct {
+					Contexts struct {
+						Nodes []struct {
+							State      string
+							Conclusion string
 						}
 					}
 				}
@@ -97,32 +91,23 @@ func (pr *PullRequest) ChecksStatus() (summary PullRequestChecksStatus) {
 		return
 	}
 	commit := pr.Commits.Nodes[0].Commit
-	for _, status := range commit.Status.Contexts {
-		switch status.State {
-		case "SUCCESS":
+	for _, c := range commit.StatusCheckRollup.Contexts.Nodes {
+		state := c.State
+		if state == "" {
+			state = c.Conclusion
+		}
+		switch state {
+		case "SUCCESS", "NEUTRAL", "SKIPPED":
 			summary.Passing++
-		case "EXPECTED", "ERROR", "FAILURE":
+		case "ERROR", "FAILURE", "CANCELLED", "TIMED_OUT", "ACTION_REQUIRED":
 			summary.Failing++
-		case "PENDING":
+		case "EXPECTED", "QUEUED", "PENDING", "IN_PROGRESS":
 			summary.Pending++
 		default:
-			panic(fmt.Errorf("unsupported status: %q", status.State))
+			panic(fmt.Errorf("unsupported status: %q", state))
 		}
 		summary.Total++
 	}
-	for _, checkSuite := range commit.CheckSuites.Nodes {
-		for _, checkRun := range checkSuite.CheckRuns.Nodes {
-			switch checkRun.Conclusion {
-			case "SUCCESS", "NEUTRAL":
-				summary.Passing++
-			case "FAILURE", "CANCELLED", "TIMED_OUT", "ACTION_REQUIRED":
-				summary.Failing++
-			default:
-				panic(fmt.Errorf("unsupported check conclusion: %q", checkRun.Conclusion))
-			}
-			summary.Total++
-		}
-	}
 	return
 }
 
@@ -267,15 +252,13 @@ func PullRequests(client *Client, ghRepo Repo, currentBranch, currentUsername st
 		commits(last: 1) {
 			nodes {
 				commit {
-					status {
-						contexts {
-							state
-						}
-					}
-					checkSuites(first: 50) {
-						nodes {
-							checkRuns(first: 50) {
-								nodes {
+					statusCheckRollup {
+						contexts(last: 100) {
+							nodes {
+								...on StatusContext {
+									state
+								}
+								...on CheckRun {
 									conclusion
 								}
 							}

command/root.go

@@ -75,6 +75,7 @@ var apiClientForContext = func(ctx context.Context) (*api.Client, error) {
 		// antiope-preview: Checks
 		// shadow-cat-preview: Draft pull requests
 		api.AddHeader("Accept", "application/vnd.github.antiope-preview+json, application/vnd.github.shadow-cat-preview"),
+		api.AddHeader("GraphQL-Features", "pe_mobile"),
 	}
 	if verbose := os.Getenv("DEBUG"); verbose != "" {
 		opts = append(opts, api.VerboseLog(os.Stderr))