fix: ensure 'evaluate all' works correctly with git sha

Author: jippi

pkg/scm/gitlab/client_merge_request.go

@@ -87,10 +87,19 @@ func (client *MergeRequestClient) List(ctx context.Context, options *scm.ListMer
 		return nil, err
 	}
 
-	hits := []scm.ListMergeRequest{}
-	for _, x := range result.Project.MergeRequests.Nodes {
-		hits = append(hits, scm.ListMergeRequest{ID: x.ID})
+	results := []scm.ListMergeRequest{}
+
+	for _, mergeRequest := range result.Project.MergeRequests.Nodes {
+		// If there are no DiffHeadSha; there are no commits on the MR; so don't process it
+		if mergeRequest.DiffHeadSha == nil {
+			continue
+		}
+
+		results = append(results, scm.ListMergeRequest{
+			ID:  mergeRequest.ID,
+			SHA: *mergeRequest.DiffHeadSha,
+		})
 	}
 
-	return hits, nil
+	return results, nil
 }

schema/gitlab.schema.graphqls

@@ -38,7 +38,7 @@ type Context {
   CurrentUser: ContextUser!
 
   "Information about the event that triggered the evaluation. Empty when not using webhook server."
-  WebhookEvent: Any @generated
+  WebhookEvent: Any @generated @expr(key: "webhook_event")
 }
 
 enum MergeRequestState {
@@ -98,7 +98,8 @@ type ListMergeRequestsProjectMergeRequestNodes {
 }
 
 type ListMergeRequestsProjectMergeRequest {
-  ID: String! @graphql(key: "iid") @internal
+  ID:          String! @graphql(key: "iid")         @internal
+  DiffHeadSha: String  @graphql(key: "diffHeadSha") @internal
 }
 
 # https://docs.gitlab.com/ee/api/graphql/reference/#project
@@ -135,9 +136,9 @@ type ContextProject {
   "Labels available on this project"
   Labels: [ContextLabel!] @generated
 
-  ResponseLabels: ContextLabelNode @internal @graphql(key: "labels(first: 200)")
-  MergeRequest: ContextMergeRequest @internal @graphql(key: "mergeRequest(iid: $mr_id)")
-  ResponseGroup: ContextGroup @internal @graphql(key: "group")
+  ResponseLabels: ContextLabelNode    @internal @graphql(key: "labels(first: 200)")
+  MergeRequest:   ContextMergeRequest @internal @graphql(key: "mergeRequest(iid: $mr_id)")
+  ResponseGroup:  ContextGroup        @internal @graphql(key: "group")
 }
 
 # https://docs.gitlab.com/ee/api/graphql/reference/#group