1 files changed, 104 insertions, 0 deletions
diff --git a/spec/tooling/danger/specs/project_factory_suggestion_spec.rb b/spec/tooling/danger/specs/project_factory_suggestion_spec.rb
new file mode 100644
index 00000000000..95ffcfb1460
--- /dev/null
+++ b/spec/tooling/danger/specs/project_factory_suggestion_spec.rb
@@ -0,0 +1,104 @@
+# frozen_string_literal: true
+
+require 'gitlab/dangerfiles/spec_helper'
+
+require_relative '../../../../tooling/danger/specs'
+require_relative '../../../../tooling/danger/project_helper'
+
+RSpec.describe Tooling::Danger::Specs::ProjectFactorySuggestion, feature_category: :tooling do
+  include_context "with dangerfile"
+
+  let(:fake_danger) { DangerSpecHelper.fake_danger.include(Tooling::Danger::Specs) }
+  let(:fake_project_helper) { instance_double('Tooling::Danger::ProjectHelper') }
+  let(:filename) { 'spec/foo_spec.rb' }
+
+  let(:template) do
+    <<~MARKDOWN.chomp
+      ```suggestion
+      %<suggested_line>s
+      ```
+
+      Project creations are very slow. Use `let_it_be`, `build` or `build_stubbed` if possible.
+      See [testing best practices](https://docs.gitlab.com/ee/development/testing_guide/best_practices.html#optimize-factory-usage)
+      for background information and alternative options.
+    MARKDOWN
+  end
+
+  let(:file_lines) do
+    [
+      " let(:project) { create(:project) }",
+      " let_it_be(:project) { create(:project, :repository)",
+      " let!(:project) { create(:project) }",
+      "   let(:var) { create(:project) }",
+      " let(:merge_request) { create(:merge_request, project: project)",
+      " context 'when merge request exists' do",
+      "   it { is_expected.to be_success }",
+      " end",
+      "   let!(:var) { create(:project) }",
+      " let(:project) { create(:thing) }",
+      " let(:project) { build(:project) }",
+      " let(:project) do",
+      "   create(:project)",
+      " end",
+      " let(:project) { create(:project, :repository) }",
+      " str = 'let(:project) { create(:project) }'",
+      " let(:project) { create(:project_empty_repo) }",
+      " let(:project) { create(:forked_project_with_submodules) }",
+      " let(:project) { create(:project_with_design) }",
+      " let(:authorization) { create(:project_authorization) }"
+    ]
+  end
+
+  let(:matching_lines) do
+    [
+      "+ let(:should_not_error) { create(:project) }",
+      "+ let(:project) { create(:project) }",
+      "+ let!(:project) { create(:project) }",
+      "+   let(:var) { create(:project) }",
+      "+   let!(:var) { create(:project) }",
+      "+ let(:project) { create(:project, :repository) }",
+      "+ let(:project) { create(:project_empty_repo) }",
+      "+ let(:project) { create(:forked_project_with_submodules) }",
+      "+ let(:project) { create(:project_with_design) }"
+    ]
+  end
+
+  let(:changed_lines) do
+    [
+      "+ line which doesn't exist in the file and should not cause an error",
+      "+ let_it_be(:project) { create(:project, :repository)",
+      "+ let(:project) { create(:thing) }",
+      "+ let(:project) do",
+      "+   create(:project)",
+      "+ end",
+      "+ str = 'let(:project) { create(:project) }'",
+      "+ let(:authorization) { create(:project_authorization) }"
+    ] + matching_lines
+  end
+
+  subject(:specs) { fake_danger.new(helper: fake_helper) }
+
+  before do
+    allow(specs).to receive(:project_helper).and_return(fake_project_helper)
+    allow(specs.helper).to receive(:changed_lines).with(filename).and_return(changed_lines)
+    allow(specs.project_helper).to receive(:file_lines).and_return(file_lines)
+  end
+
+  it 'adds suggestions at the correct lines', :aggregate_failures do
+    [
+      { suggested_line: " let_it_be(:project) { create(:project) }", number: 1 },
+      { suggested_line: " let_it_be(:project) { create(:project) }", number: 3 },
+      { suggested_line: "   let_it_be(:var) { create(:project) }", number: 4 },
+      { suggested_line: "   let_it_be(:var) { create(:project) }", number: 9 },
+      { suggested_line: " let_it_be(:project) { create(:project, :repository) }", number: 15 },
+      { suggested_line: " let_it_be(:project) { create(:project_empty_repo) }", number: 17 },
+      { suggested_line: " let_it_be(:project) { create(:forked_project_with_submodules) }", number: 18 },
+      { suggested_line: " let_it_be(:project) { create(:project_with_design) }", number: 19 }
+    ].each do |test_case|
+      comment = format(template, suggested_line: test_case[:suggested_line])
+      expect(specs).to receive(:markdown).with(comment, file: filename, line: test_case[:number])
+    end
+
+    specs.add_suggestions_for(filename)
+  end
+end