Add Sidekiq/PerformInline

config/default.yml

@@ -146,6 +146,10 @@ Sidekiq/NoNilReturn:
   Include:
     - app/workers/**/*
 
+Sidekiq/PerformInline:
+  Description: 'Suggest to use `perform_inline` instead of `new.perform` for Sidekiq workers.'
+  Enabled: true
+
 Sidekiq/SymbolArgument:
   Description: "Prevent passing keywords arguments in worker's perform method"
   Enabled: true

lib/rubocop/cop/sidekiq/perform_inline.rb

@@ -0,0 +1,41 @@
+# frozen_string_literal: true
+
+module RuboCop
+  module Cop
+    module Sidekiq
+      # Suggest to use `perform_inline` instead of `new.perform` for Sidekiq workers.
+      #
+      # @bad
+      #   MyWorker.new.perform
+      #
+      # @good
+      #   MyWorker.perform_inline
+      #
+      class PerformInline < Base
+        extend AutoCorrector
+        MSG = 'Use `perform_inline` instead of `new.perform`.'
+
+        RESTRICT_ON_SEND = %i[perform].freeze
+
+        # @!method new_perform?(node)
+        def_node_matcher :new_perform?, <<~PATTERN
+          (send (send (const nil? _) :new) :perform)
+        PATTERN
+
+        def on_send(node)
+          return unless new_perform?(node)
+
+          add_offense(node)
+        end
+
+        def autocorrect(node)
+          lambda do |corrector|
+            receiver, _method_name = *node
+            corrector.replace(receiver.source_range,
+                              receiver.source_range.source.gsub('new.perform', 'perform_inline'))
+          end
+        end
+      end
+    end
+  end
+end

spec/rubocop/cop/sidekiq/perform_inline_spec.rb

@@ -0,0 +1,22 @@
+# frozen_string_literal: true
+
+RSpec.describe RuboCop::Cop::Sidekiq::PerformInline, :config do
+  let(:config) { RuboCop::Config.new }
+
+  it 'registers an offense when using `new.perform`' do
+    expect_offense(<<~RUBY)
+      MyWorker.new.perform
+               ^^^^^^^^^^^ Sidekiq/PerformInline: Use `perform_inline` instead of `new.perform`
+    RUBY
+
+    expect_correction(<<~RUBY)
+      MyWorker.perform_inline
+    RUBY
+  end
+
+  it 'does not register an offense when using `#good_method`' do
+    expect_no_offenses(<<~RUBY)
+      MyWorker.perform_inline
+    RUBY
+  end
+end