Handle external issues in IssueReferenceFilterfix-external-issue-links

In the past this class would use Project#get_issue to retrieve an issue
by its ID. This method would automatically determine whether to return
an Issue or ExternalIssue.

This commit changes IssueReferenceFilter to handle external issues again
and in a somewhat more explicit manner than before.

Fixes gitlab-org/gitlab-ce#18827

2 files changed, 43 insertions, 3 deletions

diff --git a/lib/banzai/filter/issue_reference_filter.rb b/lib/banzai/filter/issue_reference_filter.rb
index 2614261f9eb..5351272f42d 100644
--- a/lib/banzai/filter/issue_reference_filter.rb
+++ b/lib/banzai/filter/issue_reference_filter.rb
@@ -31,10 +31,14 @@ module Banzai
           projects_per_reference.each do |path, project|
             issue_ids = references_per_project[path]
 
-            next unless project.default_issues_tracker?
+            if project.default_issues_tracker?
+              issues = project.issues.where(iid: issue_ids.to_a)
+            else
+              issues = issue_ids.map { |id| ExternalIssue.new(id, project) }
+            end
 
-            project.issues.where(iid: issue_ids.to_a).each do |issue|
-              hash[project][issue.iid] = issue
+            issues.each do |issue|
+              hash[project][issue.iid.to_i] = issue
             end
           end
 
diff --git a/spec/lib/banzai/filter/issue_reference_filter_spec.rb b/spec/lib/banzai/filter/issue_reference_filter_spec.rb
index 5b63c946114..8d6ce114aa9 100644
--- a/spec/lib/banzai/filter/issue_reference_filter_spec.rb
+++ b/spec/lib/banzai/filter/issue_reference_filter_spec.rb
@@ -198,4 +198,40 @@ describe Banzai::Filter::IssueReferenceFilter, lib: true do
       expect(doc.to_html).to match(/\(<a.+>Reference<\/a>\.\)/)
     end
   end
+
+  describe '#issues_per_Project' do
+    context 'using an internal issue tracker' do
+      it 'returns a Hash containing the issues per project' do
+        doc = Nokogiri::HTML.fragment('')
+        filter = described_class.new(doc, project: project)
+
+        expect(filter).to receive(:projects_per_reference).
+          and_return({ project.path_with_namespace => project })
+
+        expect(filter).to receive(:references_per_project).
+          and_return({ project.path_with_namespace => Set.new([issue.iid]) })
+
+        expect(filter.issues_per_project).
+          to eq({ project => { issue.iid => issue } })
+      end
+    end
+
+    context 'using an external issue tracker' do
+      it 'returns a Hash containing the issues per project' do
+        doc = Nokogiri::HTML.fragment('')
+        filter = described_class.new(doc, project: project)
+
+        expect(project).to receive(:default_issues_tracker?).and_return(false)
+
+        expect(filter).to receive(:projects_per_reference).
+          and_return({ project.path_with_namespace => project })
+
+        expect(filter).to receive(:references_per_project).
+          and_return({ project.path_with_namespace => Set.new([1]) })
+
+        expect(filter.issues_per_project[project][1]).
+          to be_an_instance_of(ExternalIssue)
+      end
+    end
+  end
 end