Merge branch 'allow_single_letter_external_issue_ids' into 'master'

Allow single letter external issue IDs

Closes #52803

See merge request gitlab-org/gitlab-ce!22717

app/models/project_services/issue_tracker_service.rb

@@ -12,9 +12,9 @@ class IssueTrackerService < Service
   # overridden patterns. See ReferenceRegexes::EXTERNAL_PATTERN
   def self.reference_pattern(only_long: false)
     if only_long
-      /(\b[A-Z][A-Z0-9_]+-)(?<issue>\d+)/
+      /(\b[A-Z][A-Z0-9_]*-)(?<issue>\d+)/
     else
-      /(\b[A-Z][A-Z0-9_]+-|#{Issue.reference_prefix})(?<issue>\d+)/
+      /(\b[A-Z][A-Z0-9_]*-|#{Issue.reference_prefix})(?<issue>\d+)/
     end
   end
 

changelogs/unreleased/22717-single-letter-identifier-external-issue-tracker.yml

+---
+title: "Allowing issues with single letter identifiers to be linked to external issue tracker (f.ex T-123)"
+merge_request: 22717
+author: Dídac Rodríguez Arbonès
+type: changed
\ No newline at end of file

spec/lib/banzai/filter/external_issue_reference_filter_spec.rb

@@ -101,15 +101,24 @@ describe Banzai::Filter::ExternalIssueReferenceFilter do
 
   context "redmine project" do
     let(:project) { create(:redmine_project) }
-    let(:issue) { ExternalIssue.new("#123", project) }
-    let(:reference) { issue.to_reference }
 
     before do
-      project.issues_enabled = false
-      project.save!
+      project.update!(issues_enabled: false)
+    end
+
+    context "with a hash prefix" do
+      let(:issue) { ExternalIssue.new("#123", project) }
+      let(:reference) { issue.to_reference }
+
+      it_behaves_like "external issue tracker"
     end
 
-    it_behaves_like "external issue tracker"
+    context "with a single-letter prefix" do
+      let(:issue) { ExternalIssue.new("T-123", project) }
+      let(:reference) { issue.to_reference }
+
+      it_behaves_like "external issue tracker"
+    end
   end
 
   context "jira project" do
@@ -122,6 +131,15 @@ describe Banzai::Filter::ExternalIssueReferenceFilter do
       it_behaves_like "external issue tracker"
     end
 
+    context "with a single-letter prefix" do
+      let(:issue) { ExternalIssue.new("J-123", project) }
+
+      it "ignores reference" do
+        exp = act = "Issue #{reference}"
+        expect(filter(act).to_html).to eq exp
+      end
+    end
+
     context "with wrong markdown" do
       let(:issue) { ExternalIssue.new("#123", project) }