Add ProcessedSource#each_comment_in_lines

Deprecate `ProcessedSource#comments_before_line`

CHANGELOG.md

@@ -8,6 +8,7 @@
 * [#85](https://github.com/rubocop-hq/rubocop-ast/pull/85): Add `IntNode#value` and `FloatNode#value`. ([@fatkodima][])
 * [#82](https://github.com/rubocop-hq/rubocop-ast/pull/82): `NodePattern`: Allow comments ([@marcandre][])
 * [#83](https://github.com/rubocop-hq/rubocop-ast/pull/83): Add `ProcessedSource#comment_at_line` ([@marcandre][])
+* [#83](https://github.com/rubocop-hq/rubocop-ast/pull/83): Add `ProcessedSource#each_comment_in_lines` ([@marcandre][])
 
 ### Bug fixes
 

lib/rubocop/ast/processed_source.rb

@@ -76,7 +76,7 @@ def each_comment(&block)
         comments.each(&block)
       end
 
-      # @deprecated Use `comments.find` or `comment_at_line`
+      # @deprecated Use `comment_at_line`, `each_comment_in_lines`, or `comments.find`
       def find_comment(&block)
         comments.find(&block)
       end
@@ -109,17 +109,29 @@ def line_with_comment?(line)
         comment_index.include?(line)
       end
 
+      # Enumerates on the comments contained with the given `line_range`
+      def each_comment_in_lines(line_range)
+        return to_enum(:each_comment_in_lines, line_range) unless block_given?
+
+        line_range.each do |line|
+          if (comment = comment_index[line])
+            yield comment
+          end
+        end
+      end
+
       # @return [Boolean] if any of the lines in the given `source_range` has a comment.
+      # Consider using `each_comment_in_lines` instead
       def contains_comment?(source_range)
-        (source_range.line..source_range.last_line).any? do |line|
-          line_with_comment?(line)
-        end
+        each_comment_in_lines(source_range.line..source_range.last_line).any?
       end
       # @deprecated use contains_comment?
       alias commented? contains_comment?
 
+      # @deprecated Use `each_comment_in_lines`
+      # Should have been called `comments_before_or_at_line`. Doubtful it has of any valid use.
       def comments_before_line(line)
-        comments.select { |c| c.location.line <= line }
+        each_comment_in_lines(0..line).to_a
       end
 
       def start_with?(string)

spec/rubocop/ast/processed_source_spec.rb

@@ -268,6 +268,15 @@ def some_method
       end
     end
 
+    describe '#each_comment_in_lines' do
+      it 'yields the comments' do
+        enum = processed_source.each_comment_in_lines(1..4)
+        expect(enum.is_a?(Enumerable)).to be(true)
+        expect(enum.to_a).to eq processed_source.comments
+        expect(processed_source.each_comment_in_lines(2..5).map(&:text)).to eq ['# comment two']
+      end
+    end
+
     describe '#line_with_comment?' do
       it 'returns true for lines with comments' do
         expect(processed_source.line_with_comment?(1)).to be true