Fix Layout/RedundantLineBreak adding extra space within method chains

changelog/fix_fix_layoutredundantlinebreak_adding.md

@@ -0,0 +1 @@
+* [#10124](https://github.com/rubocop/rubocop/pull/10124): Fix `Layout/RedundantLineBreak` adding extra space within method chains. ([@dvandersluis][])

lib/rubocop/cop/layout/dot_position.rb

@@ -109,9 +109,7 @@ def receiver_end_line(node)
 
         def last_heredoc_line(node)
           if node.send_type?
-            node.arguments.select { |arg| heredoc?(arg) }
-                .map { |arg| arg.loc.heredoc_end.line }
-                .max
+            node.arguments.select { |arg| heredoc?(arg) }.map { |arg| arg.loc.heredoc_end.line }.max
           elsif heredoc?(node)
             node.loc.heredoc_end.line
           end

lib/rubocop/cop/layout/redundant_line_break.rb

@@ -127,6 +127,7 @@ def to_single_line(source)
             .gsub(/" *\\\n\s*'/, %q(" + ')) # Double quote, backslash, and then single quote
             .gsub(/' *\\\n\s*"/, %q(' + ")) # Single quote, backslash, and then double quote
             .gsub(/(["']) *\\\n\s*\1/, '')  # Double or single quote, backslash, then same quote
+            .gsub(/\n\s*(?=\.\w)/, '')      # Extra space within method chaining
             .gsub(/\s*\\?\n\s*/, ' ')       # Any other line break, with or without backslash
         end
 

lib/rubocop/cop/mixin/heredoc.rb

@@ -21,9 +21,7 @@ def on_heredoc(_node)
       private
 
       def indent_level(str)
-        indentations = str.lines
-                          .map { |line| line[/^\s*/] }
-                          .reject { |line| line.end_with?("\n") }
+        indentations = str.lines.map { |line| line[/^\s*/] }.reject { |line| line.end_with?("\n") }
         indentations.empty? ? 0 : indentations.min_by(&:size).size
       end
 

spec/rubocop/config_loader_spec.rb

@@ -1010,8 +1010,7 @@ class Loop < Cop
           gem_class = Struct.new(:gem_dir)
           %w[gemone gemtwo].each do |gem_name|
             mock_spec = gem_class.new(File.join(gem_root, gem_name))
-            allow(Gem::Specification).to receive(:find_by_name)
-              .with(gem_name).and_return(mock_spec)
+            allow(Gem::Specification).to receive(:find_by_name).with(gem_name).and_return(mock_spec)
           end
           allow(Gem).to receive(:path).and_return([gem_root])
         end

spec/rubocop/config_spec.rb

@@ -192,8 +192,7 @@
       end
 
       it 'raises validation error' do
-        expect { configuration.validate }
-          .to raise_error(RuboCop::ValidationError, /trailing_comma/)
+        expect { configuration.validate }.to raise_error(RuboCop::ValidationError, /trailing_comma/)
       end
     end
 

spec/rubocop/cop/layout/case_indentation_spec.rb

@@ -2,8 +2,7 @@
 
 RSpec.describe RuboCop::Cop::Layout::CaseIndentation, :config do
   let(:config) do
-    merged = RuboCop::ConfigLoader
-             .default_configuration['Layout/CaseIndentation'].merge(cop_config)
+    merged = RuboCop::ConfigLoader.default_configuration['Layout/CaseIndentation'].merge(cop_config)
     RuboCop::Config.new('Layout/CaseIndentation' => merged,
                         'Layout/IndentationWidth' => { 'Width' => 2 })
   end

spec/rubocop/cop/layout/redundant_line_break_spec.rb

@@ -271,6 +271,60 @@ def resolve_inheritance_from_gems(hash)
             m(7 + 8 + 9)
         RUBY
       end
+
+      context 'method chains' do
+        it 'properly corrects a method chain on multiple lines' do
+          expect_offense(<<~RUBY)
+            foo(' .x')
+            ^^^^^^^^^^ Redundant line break detected.
+              .bar
+              .baz
+          RUBY
+
+          expect_correction(<<~RUBY)
+            foo(' .x').bar.baz
+          RUBY
+        end
+
+        it 'registers an offense and corrects with a arguments on multiple lines' do
+          expect_offense(<<~RUBY)
+            foo(x,
+            ^^^^^^ Redundant line break detected.
+                y,
+                z)
+              .bar
+              .baz
+          RUBY
+
+          expect_correction(<<~RUBY)
+            foo(x, y, z).bar.baz
+          RUBY
+        end
+
+        it 'registers an offense and corrects with a string argument on multiple lines' do
+          expect_offense(<<~RUBY)
+            foo('....' \\
+            ^^^^^^^^^^^^ Redundant line break detected.
+                '....')
+              .bar
+              .baz
+          RUBY
+
+          expect_correction(<<~RUBY)
+            foo('........').bar.baz
+          RUBY
+        end
+
+        it 'does not register an offense with a heredoc argument' do
+          expect_no_offenses(<<~RUBY)
+            foo(<<~EOS)
+              xyz
+            EOS
+              .bar
+              .baz
+          RUBY
+        end
+      end
     end
 
     context 'for an expression that does not fit on a single line' do

spec/rubocop/options_spec.rb

@@ -365,8 +365,7 @@ def abs(path)
       end
 
       it 'fails if given without --auto-gen-config' do
-        expect { options.parse %w[--exclude-limit 10] }
-          .to raise_error(RuboCop::OptionArgumentError)
+        expect { options.parse %w[--exclude-limit 10] }.to raise_error(RuboCop::OptionArgumentError)
       end
     end
 

spec/rubocop/result_cache_spec.rb

@@ -226,8 +226,7 @@ def abs(path)
             cache2.save(offenses)
 
             expect(cache2.valid?).to eq(true)
-            expect($stderr.string)
-              .not_to match(/Warning: .* is a symlink, which is not allowed.\n/)
+            expect($stderr.string).not_to match(/Warning: .* is a symlink, which is not allowed.\n/)
           end
         end
       end