From 76d975524e02b723dec19620f3a973df913ae309 Mon Sep 17 00:00:00 2001
From: Chris Westra <bestra@github.com>
Date: Fri, 16 Sep 2022 12:12:25 -0400
Subject: [PATCH] Add feature detection query

---
 api/queries_branch_issue_reference.go | 22 ++++++++++++++++++++++
 pkg/cmd/issue/develop/develop.go      | 10 ++++++++++
 2 files changed, 32 insertions(+)

diff --git a/api/queries_branch_issue_reference.go b/api/queries_branch_issue_reference.go
index 3f6f66966..6626bea7f 100644
--- a/api/queries_branch_issue_reference.go
+++ b/api/queries_branch_issue_reference.go
@@ -132,6 +132,28 @@ func ListLinkedBranches(client *Client, repo ghrepo.Interface, issueNumber int)
 
 }
 
+// introspects the schema to see if we expose the LinkedBranch type
+func CheckLinkedBranchFeature(client *Client, host string) (err error) {
+	var featureDetection struct {
+		Name struct {
+			Fields []struct {
+				Name string
+			}
+		} `graphql:"LinkedBranch: __type(name: \"LinkedBranch\")"`
+	}
+
+	err = client.Query(host, "LinkedBranch_fields", &featureDetection, nil)
+
+	if err != nil {
+		return err
+	}
+
+	if len(featureDetection.Name.Fields) == 0 {
+		return fmt.Errorf("the `gh issue develop` command is not currently available")
+	}
+	return nil
+}
+
 // This fetches the oids for the repo's default branch (`main`, etc) and the name the user might have provided in one shot.
 func FindBaseOid(client *Client, repo *Repository, ref string) (string, string, error) {
 	query := `
diff --git a/pkg/cmd/issue/develop/develop.go b/pkg/cmd/issue/develop/develop.go
index 39dca8820..d209121f7 100644
--- a/pkg/cmd/issue/develop/develop.go
+++ b/pkg/cmd/issue/develop/develop.go
@@ -84,6 +84,11 @@ func developRunCreate(opts *DevelopOptions) (err error) {
 	}
 
 	opts.IO.StartProgressIndicator()
+	err = api.CheckLinkedBranchFeature(apiClient, baseRepo.RepoHost())
+	if err != nil {
+		return err
+	}
+
 	repo, err := api.GitHubRepo(apiClient, baseRepo)
 	if err != nil {
 		return err
@@ -190,6 +195,11 @@ func developRunList(opts *DevelopOptions) (err error) {
 	}
 
 	opts.IO.StartProgressIndicator()
+
+	err = api.CheckLinkedBranchFeature(apiClient, baseRepo.RepoHost())
+	if err != nil {
+		return err
+	}
 	issueNumber, issueRepo, err := issueMetadata(opts.IssueSelector, opts.IssueRepoSelector, baseRepo)
 	if err != nil {
 		return err