E2E tests for unusual names in branches and files

See https://gitlab.com/gitlab-com/www-gitlab-com/-/issues/7228

qa/qa/specs/features/browser_ui/3_create/repository/branch_with_unusual_name_spec.rb

+# frozen_string_literal: true
+
+module QA
+  RSpec.describe 'Create' do
+    describe 'Branch with unusual name' do
+      let(:branch_name) { 'unUsually/named#br--anch' }
+      let(:project) do
+        Resource::Project.fabricate_via_api! do |resource|
+          resource.name = 'unusually-named-branch-project'
+          resource.initialize_with_readme = true
+        end
+      end
+
+      before do
+        Flow::Login.sign_in
+      end
+
+      context 'when branch name contains slash, hash, double dash, and capital letter' do
+        it 'renders repository file tree correctly', testcase: 'https://gitlab.com/gitlab-org/quality/testcases/-/issues/1780' do
+          Resource::Repository::Commit.fabricate_via_api! do |commit|
+            commit.project = project
+            commit.branch = branch_name
+            commit.start_branch = project.default_branch
+            commit.commit_message = 'Add new file'
+            commit.add_files([
+                                 { file_path: 'test-folder/test-file.md', content: 'new content' }
+                             ])
+          end
+
+          project.visit!
+
+          Page::Project::Show.perform do |show|
+            show.switch_to_branch(branch_name)
+            show.click_file('test-folder')
+
+            expect(show).to have_file('test-file.md')
+
+            show.click_file('test-file.md')
+
+            expect(show).to have_content('new content')
+          end
+        end
+      end
+    end
+  end
+end

qa/qa/specs/features/browser_ui/3_create/repository/file/file_with_unusual_name_spec.rb

+# frozen_string_literal: true
+
+module QA
+  RSpec.describe 'Create' do
+    describe 'File with unusual name' do
+      let(:file_name) { '-un:usually;named#file?.md' }
+      let(:project) do
+        Resource::Project.fabricate_via_api! do |resource|
+          resource.name = 'unusually-named-file-project'
+          resource.initialize_with_readme = true
+        end
+      end
+
+      before do
+        Flow::Login.sign_in
+      end
+
+      context 'when file name starts with a dash and contains hash, semicolon, colon, and question mark' do
+        it 'renders repository file tree correctly', testcase: 'https://gitlab.com/gitlab-org/quality/testcases/-/issues/1779' do
+          Resource::File.fabricate_via_api! do |file|
+            file.project = project
+            file.commit_message = 'Add new file'
+            file.name = "test-folder/#{file_name}"
+            file.content = "### Heading\n\n[Gitlab link](https://gitlab.com/)"
+          end
+
+          project.visit!
+
+          Page::Project::Show.perform do |show|
+            show.click_file('test-folder')
+
+            expect(show).to have_file(file_name)
+
+            show.click_file(file_name)
+
+            aggregate_failures 'markdown file contents' do
+              expect(show).to have_content('Heading')
+              expect(show).to have_content('Gitlab link')
+              expect(show).not_to have_content('###')
+              expect(show).not_to have_content('https://gitlab.com/')
+            end
+          end
+        end
+      end
+    end
+  end
+end