[ruby/syntax_suggest] Preserve whitespace in front of comments

When removing comments I previously replaced them with a newline. This loses some context and may affect the order of the indent search which in turn affects the final result. By preserving whitespace in front of the comment, we preserve the "natural" indentation order of the line while also allowing the parser/lexer to see and join naturally consecutive (method chain) lines.

close https://github.com/ruby/syntax_suggest/pull/177

lib/syntax_suggest/clean_document.rb

@@ -110,7 +110,7 @@ module SyntaxSuggest
       @document.join
     end
 
-    # Remove comments and whitespace only lines
+    # Remove comments
     #
     # replace with empty newlines
     #
@@ -156,8 +156,9 @@ module SyntaxSuggest
     #
     def clean_sweep(source:)
       source.lines.map do |line|
-        if line.match?(/^\s*(#[^{].*)?$/) # https://rubular.com/r/LLE10D8HKMkJvs
-          $/
+        if line.match?(/^\s*#([^{].*)?$/) # https://rubular.com/r/LLE10D8HKMkJvs
+          whitespace = /^(?<whitespace>\s*)#([^{].*)?$/.match(line).named_captures["whitespace"] || ""
+          whitespace + $/
         else
           line
         end

lib/syntax_suggest/code_line.rb

@@ -48,11 +48,9 @@ module SyntaxSuggest
       strip_line = line.dup
       strip_line.lstrip!
 
-      if strip_line.empty?
-        @empty = true
-        @indent = 0
+      if (@empty = strip_line.empty?)
+        @indent = line.length - 1 # Newline removed from strip_line is not "whitespace"
       else
-        @empty = false
         @indent = line.length - strip_line.length
       end
 

spec/syntax_suggest/integration/syntax_suggest_spec.rb

@@ -207,5 +207,32 @@ module SyntaxSuggest
         > 4  end
       EOM
     end
+
+    it "comment inside of a method" do
+      source = <<~'EOM'
+        class Dog
+          def bark
+            # todo
+          end
+
+          def sit
+            print "sit"
+          end
+        end
+        end # extra end
+      EOM
+
+      io = StringIO.new
+      SyntaxSuggest.call(
+        io: io,
+        source: source
+      )
+      out = io.string
+      expect(out).to include(<<~EOM)
+        >  1  class Dog
+        >  9  end
+        > 10  end # extra end
+      EOM
+    end
   end
 end

spec/syntax_suggest/unit/clean_document_spec.rb

@@ -72,6 +72,25 @@ module SyntaxSuggest
       EOM
     end
 
+
+    it "joins multi-line chained methods when separated by comments" do
+      source = <<~EOM
+        User.
+          # comment
+          where(name: 'schneems').
+          # another comment
+          first
+      EOM
+
+      doc = CleanDocument.new(source: source).join_consecutive!
+      code_lines = doc.lines
+
+      expect(code_lines[0].to_s.count($/)).to eq(5)
+      code_lines[1..-1].each do |line|
+        expect(line.to_s.strip.length).to eq(0)
+      end
+    end
+
     it "helper method: take_while_including" do
       source = <<~EOM
         User
@@ -92,27 +111,10 @@ module SyntaxSuggest
           # yolo
       EOM
 
-      out = CleanDocument.new(source: source).lines.join
-      expect(out.to_s).to eq(<<~EOM)
-
-        puts "what"
-
-      EOM
-    end
-
-    it "whitespace: removes whitespace" do
-      source = "  \n" + <<~EOM
-        puts "what"
-      EOM
-
-      out = CleanDocument.new(source: source).lines.join
-      expect(out.to_s).to eq(<<~EOM)
-
-        puts "what"
-      EOM
-
-      expect(source.lines.first.to_s).to_not eq("\n")
-      expect(out.lines.first.to_s).to eq("\n")
+      lines = CleanDocument.new(source: source).lines
+      expect(lines[0].to_s).to eq($/)
+      expect(lines[1].to_s).to eq('puts "what"' + $/)
+      expect(lines[2].to_s).to eq('  ' + $/)
     end
 
     it "trailing slash: does not join trailing do" do

spec/syntax_suggest/unit/code_line_spec.rb

@@ -48,6 +48,7 @@ module SyntaxSuggest
       # Indicates line 1 can join 2, 2 can join 3, but 3 won't join it's next line
       expect(code_lines.map(&:ignore_newline_not_beg?)).to eq([true, true, false, false])
     end
+
     it "trailing if" do
       code_lines = CodeLine.from_source(<<~'EOM')
         puts "lol" if foo

spec/syntax_suggest/unit/code_search_spec.rb

@@ -338,6 +338,7 @@ module SyntaxSuggest
             end
           EOM
           search.call
+          puts "done"
 
           expect(search.invalid_blocks.join).to eq(<<~'EOM')
             Foo.call do