Separately query viewerMergeBodyText for GHE compatibility

mislav · mislav · commit 12cf8ef65b68 · 2021-02-17T14:06:27.000+01:00
GHE versions 2.22 and older will not have this GraphQL field. Avoid the
resulting error and have the command proceeed with empty text as the
default.
diff --git a/api/queries_pr.go b/api/queries_pr.go
@@ -88,8 +88,6 @@ type PullRequest struct {
 	ReactionGroups ReactionGroups
 	Reviews        PullRequestReviews
 	ReviewRequests ReviewRequests
-
-	ViewerMergeBodyText string
 }
 
 type ReviewRequests struct {
@@ -578,7 +576,6 @@ func PullRequestByNumber(client *Client, repo ghrepo.Interface, number int) (*Pu
 				milestone{
 					title
 				}
-				viewerMergeBodyText
 				` + commentsFragment() + `
 				` + reactionGroupsFragment() + `
 			}
diff --git a/pkg/cmd/pr/merge/http.go b/pkg/cmd/pr/merge/http.go
@@ -3,6 +3,7 @@ package merge
 import (
 	"context"
 	"net/http"
+	"strings"
 
 	"github.com/cli/cli/internal/ghinstance"
 	"github.com/cli/cli/internal/ghrepo"
@@ -98,3 +99,40 @@ func disableAutoMerge(client *http.Client, repo ghrepo.Interface, prID string) e
 	gql := graphql.NewClient(ghinstance.GraphQLEndpoint(repo.RepoHost()), client)
 	return gql.MutateNamed(context.Background(), "PullRequestAutoMergeDisable", &mutation, variables)
 }
+
+func getMergeText(client *http.Client, repo ghrepo.Interface, prID string, mergeMethod PullRequestMergeMethod) (string, error) {
+	var method githubv4.PullRequestMergeMethod
+	switch mergeMethod {
+	case PullRequestMergeMethodMerge:
+		method = githubv4.PullRequestMergeMethodMerge
+	case PullRequestMergeMethodRebase:
+		method = githubv4.PullRequestMergeMethodRebase
+	case PullRequestMergeMethodSquash:
+		method = githubv4.PullRequestMergeMethodSquash
+	}
+
+	var query struct {
+		Node struct {
+			PullRequest struct {
+				ViewerMergeBodyText string `graphql:"viewerMergeBodyText(mergeType: $method)"`
+			} `graphql:"...on PullRequest"`
+		} `graphql:"node(id: $prID)"`
+	}
+
+	variables := map[string]interface{}{
+		"prID":   githubv4.ID(prID),
+		"method": method,
+	}
+
+	gql := graphql.NewClient(ghinstance.GraphQLEndpoint(repo.RepoHost()), client)
+	err := gql.QueryNamed(context.Background(), "PullRequestMergeText", &query, variables)
+	if err != nil {
+		// Tolerate this API missing in older GitHub Enterprise
+		if strings.Contains(err.Error(), "Field 'viewerMergeBodyText' doesn't exist") {
+			return "", nil
+		}
+		return "", err
+	}
+
+	return query.Node.PullRequest.ViewerMergeBodyText, nil
+}
diff --git a/pkg/cmd/pr/merge/merge.go b/pkg/cmd/pr/merge/merge.go
@@ -204,11 +204,10 @@ func mergeRun(opts *MergeOptions) error {
 					return err
 				}
 
-				if payload.commitBody == "" {
-					if payload.method == PullRequestMergeMethodMerge {
-						payload.commitBody = pr.Title
-					} else {
-						payload.commitBody = pr.ViewerMergeBodyText
+				if !payload.setCommitBody {
+					payload.commitBody, err = getMergeText(httpClient, baseRepo, pr.ID, payload.method)
+					if err != nil {
+						return err
 					}
 				}
 
diff --git a/pkg/cmd/pr/merge/merge_test.go b/pkg/cmd/pr/merge/merge_test.go
@@ -703,6 +703,12 @@ func TestPRMerge_interactiveSquashEditCommitMsg(t *testing.T) {
 			"rebaseMergeAllowed": true,
 			"squashMergeAllowed": true
 		} } }`))
+	http.Register(
+		httpmock.GraphQL(`query PullRequestMergeText\b`),
+		httpmock.StringResponse(`
+		{ "data": { "node": {
+			"viewerMergeBodyText": ""
+		} } }`))
 	http.Register(
 		httpmock.GraphQL(`mutation PullRequestMerge\b`),
 		httpmock.GraphQLMutation(`{}`, func(input map[string]interface{}) {

Original file line number	Diff line number	Diff line change
`@@ -88,8 +88,6 @@ type PullRequest struct {`
`88`	`88`	`ReactionGroups ReactionGroups`
`89`	`89`	`Reviews PullRequestReviews`
`90`	`90`	`ReviewRequests ReviewRequests`
`91`		`-`
`92`		`- ViewerMergeBodyText string`
`93`	`91`	`}`
`94`	`92`
`95`	`93`	`type ReviewRequests struct {`
`@@ -578,7 +576,6 @@ func PullRequestByNumber(client Client, repo ghrepo.Interface, number int) (Pu`
`578`	`576`	`milestone{`
`579`	`577`	`title`
`580`	`578`	`}`
`581`		`- viewerMergeBodyText`
`582`	`579`	` + commentsFragment() + `
`583`	`580`	` + reactionGroupsFragment() + `
`584`	`581`	`}`
Original file line number	Diff line number	Diff line change
`@@ -204,11 +204,10 @@ func mergeRun(opts *MergeOptions) error {`
`204`	`204`	`return err`
`205`	`205`	`}`
`206`	`206`
`207`		`- if payload.commitBody == "" {`
`208`		`- if payload.method == PullRequestMergeMethodMerge {`
`209`		`- payload.commitBody = pr.Title`
`210`		`- } else {`
`211`		`- payload.commitBody = pr.ViewerMergeBodyText`
	`207`	`+ if !payload.setCommitBody {`
	`208`	`+ payload.commitBody, err = getMergeText(httpClient, baseRepo, pr.ID, payload.method)`
	`209`	`+ if err != nil {`
	`210`	`+ return err`
`212`	`211`	`}`
`213`	`212`	`}`
`214`	`213`