[Fix #9770] Update Lint/EmptyBlock to handle procs the same way as …

…lambdas.

changelog/change_update_lintemptyblock_to_handle_procs.md

@@ -0,0 +1 @@
+* [#9770](https://github.com/rubocop/rubocop/issues/9770): Update `Lint/EmptyBlock` to handle procs the same way as lambdas. ([@dvandersluis][])

lib/rubocop/cop/lint/empty_block.rb

@@ -7,7 +7,11 @@ module Lint
       # Such empty blocks are typically an oversight or we should provide a comment
       # be clearer what we're aiming for.
       #
-      # Empty lambdas are ignored by default.
+      # Empty lambdas and procs are ignored by default.
+      #
+      # NOTE: For backwards compatibility, the configuration that allows/disallows
+      # empty lambdas and procs is called `AllowEmptyLambdas`, even though it also
+      # applies to procs.
       #
       # @example
       #   # bad
@@ -40,6 +44,10 @@ module Lint
       #   end
       #   (callable || placeholder).call
       #
+      #   proc { }
+      #
+      #   Proc.new { }
+      #
       # @example AllowEmptyLambdas: false
       #   # bad
       #   allow(subject).to receive(:callable).and_return(-> {})
@@ -48,12 +56,16 @@ module Lint
       #   end
       #   (callable || placeholder).call
       #
+      #   proc { }
+      #
+      #   Proc.new { }
+      #
       class EmptyBlock < Base
         MSG = 'Empty block detected.'
 
         def on_block(node)
           return if node.body
-          return if allow_empty_lambdas? && node.lambda?
+          return if allow_empty_lambdas? && lambda_or_proc?(node)
           return if cop_config['AllowComments'] && allow_comment?(node)
 
           add_offense(node)
@@ -76,6 +88,10 @@ def comment_disables_cop?(comment)
           regexp_pattern = "# rubocop : (disable|todo) ([^,],)* (all|#{cop_name})"
           Regexp.new(regexp_pattern.gsub(' ', '\s*')).match?(comment)
         end
+
+        def lambda_or_proc?(node)
+          node.lambda? || node.proc?
+        end
       end
     end
   end

spec/rubocop/cop/lint/empty_block_spec.rb

@@ -43,6 +43,32 @@
     RUBY
   end
 
+  it 'does not register an offense on an empty proc' do
+    expect_no_offenses(<<~RUBY)
+      proc do
+      end
+    RUBY
+  end
+
+  it 'does not register an offense on an empty Proc.new' do
+    expect_no_offenses(<<~RUBY)
+      Proc.new {}
+    RUBY
+  end
+
+  it 'does not register an offense on an empty ::Proc.new' do
+    expect_no_offenses(<<~RUBY)
+      ::Proc.new {}
+    RUBY
+  end
+
+  it 'registers an offense for an empty block given to a non-Kernel `proc` method' do
+    expect_offense(<<~RUBY)
+      Foo.proc {}
+      ^^^^^^^^^^^ Empty block detected.
+    RUBY
+  end
+
   context 'when AllowComments is false' do
     let(:cop_config) { { 'AllowComments' => false } }
 
@@ -80,5 +106,27 @@
         ^^^^^ Empty block detected.
       RUBY
     end
+
+    it 'registers an offense on an empty proc' do
+      expect_offense(<<~RUBY)
+        proc do
+        ^^^^^^^ Empty block detected.
+        end
+      RUBY
+    end
+
+    it 'registers an offense on an empty Proc.new' do
+      expect_offense(<<~RUBY)
+        Proc.new {}
+        ^^^^^^^^^^^ Empty block detected.
+      RUBY
+    end
+
+    it 'registers an offense on an empty ::Proc.new' do
+      expect_offense(<<~RUBY)
+        ::Proc.new {}
+        ^^^^^^^^^^^^^ Empty block detected.
+      RUBY
+    end
   end
 end