Add no sleep cop

It checks that feature specs do not use `sleep` greater than 1 second.

config/default.yml

@@ -8,6 +8,11 @@ OpenProject/NoDoEndBlockWithRSpecCapybaraMatcherInExpect:
   Enabled: true
   VersionAdded: '0.1.0'
 
+OpenProject/NoSleepInFeatureSpecs:
+  Description: 'Avoid using `sleep` greater than 1 second in feature specs.'
+  Enabled: true
+  VersionAdded: '0.1.0'
+
 OpenProject/UseServiceResultFactoryMethods:
   Description: 'Use ServiceResult factory methods instead of ServiceResult.new.'
   Enabled: true

lib/rubocop/cop/open_project/no_sleep_in_feature_specs.rb

@@ -0,0 +1,65 @@
+# frozen_string_literal: true
+
+module RuboCop
+  module Cop
+    module OpenProject
+      # Checks that feature specs do not use `sleep` greater than 1 second.
+      #
+      # Relying on `sleep` for synchronization reduces overall performance of
+      # the test suite. Consider using Capybara `have_*` matchers or
+      # rspec-wait `wait_for` method instead.
+      #
+      # @example
+      #
+      #   # bad
+      #   sleep 20
+      #
+      #   # bad
+      #   sleep 1.5
+      #
+      #   # bad
+      #   delay = 15
+      #   sleep delay
+      #
+      #   # good (use sparingly)
+      #   sleep 1
+      #
+      #   # good
+      #   expect(page).not_to have_text("please wait")
+      #
+      #   # good
+      #   expect(page).to have_text("success")
+      #
+      #   good
+      #   wait_for { work_package.reload.subject }.to eq("Updated name")
+      class NoSleepInFeatureSpecs < Base
+        MSG = "Avoid using `sleep` greater than 1 second in feature specs. " \
+              "It will reduce overall performance of the test suite. " \
+              "Consider using Capybara `have_*` matchers or rspec-wait " \
+              "`wait_for` method instead."
+
+        def_node_matcher :sleep_call?, "(send nil? :sleep $...)"
+
+        def on_send(node)
+          return unless feature_spec?(processed_source)
+
+          sleep_call?(node) do |args|
+            add_offense(node, message: MSG) if sleeping_too_much?(args[0])
+          end
+        end
+
+        private
+
+        def sleeping_too_much?(arg)
+          return false if arg&.numeric_type? && arg.value.between?(0, 1)
+
+          true
+        end
+
+        def feature_spec?(source)
+          source.file_path.include?("_spec.rb") && source.file_path.include?("features/")
+        end
+      end
+    end
+  end
+end

lib/rubocop/cop/open_project_cops.rb

@@ -3,3 +3,4 @@
 require_relative "open_project/add_preview_for_view_component"
 require_relative "open_project/no_do_end_block_with_rspec_capybara_matcher_in_expect"
 require_relative "open_project/use_service_result_factory_methods"
+require_relative "open_project/no_sleep_in_feature_specs"

spec/rubocop/cop/open_project/no_sleep_in_feature_specs_spec.rb

@@ -0,0 +1,34 @@
+# frozen_string_literal: true
+
+RSpec.describe RuboCop::Cop::OpenProject::NoSleepInFeatureSpecs, :config do
+  let(:config) { RuboCop::Config.new }
+
+  it "registers an offense for sleeping more than 1 second in a feature spec" do
+    expect_offense(<<~RUBY, "spec/features/some_spec.rb")
+      sleep 1.5
+      ^^^^^^^^^ OpenProject/NoSleepInFeatureSpecs: #{described_class::MSG}
+      sleep 20
+      ^^^^^^^^ OpenProject/NoSleepInFeatureSpecs: #{described_class::MSG}
+      sleep
+      ^^^^^ OpenProject/NoSleepInFeatureSpecs: #{described_class::MSG}
+    RUBY
+
+    expect_no_corrections
+  end
+
+  it "does not register an offense in non-feature specs" do
+    expect_no_offenses(<<~RUBY, "spec/some_spec.rb")
+      sleep 1.5
+    RUBY
+  end
+
+  it "registers an offense sleep is called with a non-numeric argument" do
+    expect_offense(<<~RUBY, "spec/features/some_spec.rb")
+      delay = 15
+      sleep delay
+      ^^^^^^^^^^^ OpenProject/NoSleepInFeatureSpecs: #{described_class::MSG}
+    RUBY
+
+    expect_no_corrections
+  end
+end