Enable issue list pagination

Makes it possible to set a `--limit` greater than 100.

api/queries_issue.go

@@ -185,20 +185,23 @@ func IssueList(client *Client, repo ghrepo.Interface, state string, labels []str
 	}
 
 	query := fragments + `
-    query($owner: String!, $repo: String!, $limit: Int, $states: [IssueState!] = OPEN, $labels: [String!], $assignee: String) {
+    query($owner: String!, $repo: String!, $limit: Int, $endCursor: String, $states: [IssueState!] = OPEN, $labels: [String!], $assignee: String) {
       repository(owner: $owner, name: $repo) {
 		hasIssuesEnabled
-        issues(first: $limit, orderBy: {field: CREATED_AT, direction: DESC}, states: $states, labels: $labels, filterBy: {assignee: $assignee}) {
+        issues(first: $limit, after: $endCursor, orderBy: {field: CREATED_AT, direction: DESC}, states: $states, labels: $labels, filterBy: {assignee: $assignee}) {
           nodes {
             ...issue
           }
+          pageInfo {
+            hasNextPage
+            endCursor
+          }
         }
       }
     }
   `
 
 	variables := map[string]interface{}{
-		"limit":  limit,
 		"owner":  repo.RepoOwner(),
 		"repo":   repo.RepoName(),
 		"states": states,
@@ -210,25 +213,49 @@ func IssueList(client *Client, repo ghrepo.Interface, state string, labels []str
 		variables["assignee"] = assigneeString
 	}
 
-	var resp struct {
+	var response struct {
 		Repository struct {
 			Issues struct {
-				Nodes []Issue
+				Nodes    []Issue
+				PageInfo struct {
+					HasNextPage bool
+					EndCursor   string
+				}
 			}
 			HasIssuesEnabled bool
 		}
 	}
 
-	err := client.GraphQL(query, variables, &resp)
-	if err != nil {
-		return nil, err
+	var issues []Issue
+	pageLimit := min(limit, 100)
+
+loop:
+	for {
+		variables["limit"] = pageLimit
+		err := client.GraphQL(query, variables, &response)
+		if err != nil {
+			return nil, err
+		}
+		if !response.Repository.HasIssuesEnabled {
+			return nil, fmt.Errorf("the '%s' repository has disabled issues", ghrepo.FullName(repo))
+		}
+
+		for _, issue := range response.Repository.Issues.Nodes {
+			issues = append(issues, issue)
+			if len(issues) == limit {
+				break loop
+			}
+		}
+
+		if response.Repository.Issues.PageInfo.HasNextPage {
+			variables["endCursor"] = response.Repository.Issues.PageInfo.EndCursor
+			pageLimit = min(pageLimit, limit-len(issues))
+		} else {
+			break
+		}
 	}
 
-	if !resp.Repository.HasIssuesEnabled {
-		return nil, fmt.Errorf("the '%s' repository has disabled issues", ghrepo.FullName(repo))
-	}
-
-	return resp.Repository.Issues.Nodes, nil
+	return issues, nil
 }
 
 func IssueByNumber(client *Client, repo ghrepo.Interface, number int) (*Issue, error) {

api/queries_issue_test.go

@@ -0,0 +1,68 @@
+package api
+
+import (
+	"bytes"
+	"encoding/json"
+	"io/ioutil"
+	"testing"
+
+	"github.com/cli/cli/internal/ghrepo"
+)
+
+func TestIssueList(t *testing.T) {
+	http := &FakeHTTP{}
+	client := NewClient(ReplaceTripper(http))
+
+	http.StubResponse(200, bytes.NewBufferString(`
+	{ "data": { "repository": {
+		"hasIssuesEnabled": true,
+		"issues": {
+			"nodes": [],
+			"pageInfo": {
+				"hasNextPage": true,
+				"endCursor": "ENDCURSOR"
+			}
+		}
+	} } }
+	`))
+	http.StubResponse(200, bytes.NewBufferString(`
+	{ "data": { "repository": {
+		"hasIssuesEnabled": true,
+		"issues": {
+			"nodes": [],
+			"pageInfo": {
+				"hasNextPage": false,
+				"endCursor": "ENDCURSOR"
+			}
+		}
+	} } }
+	`))
+
+	_, err := IssueList(client, ghrepo.FromFullName("OWNER/REPO"), "open", []string{}, "", 251)
+	if err != nil {
+		t.Fatalf("unexpected error: %v", err)
+	}
+
+	if len(http.Requests) != 2 {
+		t.Fatalf("expected 2 HTTP requests, seen %d", len(http.Requests))
+	}
+	var reqBody struct {
+		Query     string
+		Variables map[string]interface{}
+	}
+
+	bodyBytes, _ := ioutil.ReadAll(http.Requests[0].Body)
+	json.Unmarshal(bodyBytes, &reqBody)
+	if reqLimit := reqBody.Variables["limit"].(float64); reqLimit != 100 {
+		t.Errorf("expected 100, got %v", reqLimit)
+	}
+	if _, cursorPresent := reqBody.Variables["endCursor"]; cursorPresent {
+		t.Error("did not expect first request to pass 'endCursor'")
+	}
+
+	bodyBytes, _ = ioutil.ReadAll(http.Requests[1].Body)
+	json.Unmarshal(bodyBytes, &reqBody)
+	if endCursor := reqBody.Variables["endCursor"].(string); endCursor != "ENDCURSOR" {
+		t.Errorf("expected %q, got %q", "ENDCURSOR", endCursor)
+	}
+}