Prevent duplicate issues when importing from CSV

We send the notification email in a separate job so that we do not
insert the issues again when the job is retried because email sending
failed

app/services/issues/import_csv_service.rb

@@ -46,7 +46,7 @@ module Issues
     end
 
     def email_results_to_user
-      Notify.import_issues_csv_email(@user.id, @project.id, @results).deliver_now
+      Notify.import_issues_csv_email(@user.id, @project.id, @results).deliver_later
     end
 
     def detect_col_sep(header)

changelogs/unreleased/220051-duplicate-issues-created-when-importing-from-csv.yml

+---
+title: Prevent duplicate issues when importing from CSV
+merge_request: 33626
+author:
+type: fixed

spec/services/issues/import_csv_service_spec.rb

@@ -18,9 +18,7 @@ describe Issues::ImportCsvService do
       let(:file) { fixture_file_upload('spec/fixtures/banana_sample.gif') }
 
       it 'returns invalid file error' do
-        expect_next_instance_of(Notify) do |instance|
-          expect(instance).to receive(:import_issues_csv_email)
-        end
+        expect(Notify).to receive_message_chain(:import_issues_csv_email, :deliver_later)
 
         expect(subject[:success]).to eq(0)
         expect(subject[:parse_error]).to eq(true)
@@ -31,9 +29,7 @@ describe Issues::ImportCsvService do
       let(:file) { fixture_file_upload('spec/fixtures/csv_gitlab_export.csv') }
 
       it 'imports the CSV without errors' do
-        expect_next_instance_of(Notify) do |instance|
-          expect(instance).to receive(:import_issues_csv_email)
-        end
+        expect(Notify).to receive_message_chain(:import_issues_csv_email, :deliver_later)
 
         expect(subject[:success]).to eq(4)
         expect(subject[:error_lines]).to eq([])
@@ -54,9 +50,7 @@ describe Issues::ImportCsvService do
       let(:file) { fixture_file_upload('spec/fixtures/csv_comma.csv') }
 
       it 'imports CSV without errors' do
-        expect_next_instance_of(Notify) do |instance|
-          expect(instance).to receive(:import_issues_csv_email)
-        end
+        expect(Notify).to receive_message_chain(:import_issues_csv_email, :deliver_later)
 
         expect(subject[:success]).to eq(3)
         expect(subject[:error_lines]).to eq([])
@@ -77,9 +71,7 @@ describe Issues::ImportCsvService do
       let(:file) { fixture_file_upload('spec/fixtures/csv_tab.csv') }
 
       it 'imports CSV with some error rows' do
-        expect_next_instance_of(Notify) do |instance|
-          expect(instance).to receive(:import_issues_csv_email)
-        end
+        expect(Notify).to receive_message_chain(:import_issues_csv_email, :deliver_later)
 
         expect(subject[:success]).to eq(2)
         expect(subject[:error_lines]).to eq([3])
@@ -100,9 +92,7 @@ describe Issues::ImportCsvService do
       let(:file) { fixture_file_upload('spec/fixtures/csv_semicolon.csv') }
 
       it 'imports CSV with a blank row' do
-        expect_next_instance_of(Notify) do |instance|
-          expect(instance).to receive(:import_issues_csv_email)
-        end
+        expect(Notify).to receive_message_chain(:import_issues_csv_email, :deliver_later)
 
         expect(subject[:success]).to eq(3)
         expect(subject[:error_lines]).to eq([4])