Fix steep:ignore does not work with CR/LF

lib/steep/ast/ignore.rb

@@ -93,15 +93,14 @@ def ignored_diagnostics
       def self.parse(comment, buffer)
         return unless comment.inline?
 
-        comment_location = RBS::Location.new(buffer, comment.loc.expression.begin_pos, comment.loc.expression.end_pos)
+        begin_pos = buffer.loc_to_pos([comment.loc.line, comment.loc.column])
+        end_pos = buffer.loc_to_pos([comment.loc.last_line, comment.loc.last_column])
+        comment_location = RBS::Location.new(buffer, begin_pos, end_pos)
         scanner = BufferScanner.new(comment_location)
 
         scanner.scan(/#/)
         scanner.skip(/\s*/)
 
-        begin_pos = comment.location.expression.begin_pos
-        end_pos = comment.location.expression.end_pos
-
         case
         when loc = scanner.scan(/steep:ignore:start\b/)
           scanner.skip(/\s*/)

test/ast/ignore_test.rb

@@ -108,4 +108,19 @@ def test_parse_ignore__diagnostics
       assert_equal "steep:ignore Foo, Bar,", ignore.location.source
     end
   end
+
+  def test_parse_ignore__crlf
+    _, comments, buf = parse(<<~RUBY)
+      \r
+      # steep:ignore Foo
+      # steep:ignore Foo, Bar,
+    RUBY
+    Steep::AST::Ignore.parse(comments[0], buf).tap do |ignore|
+      assert_instance_of Ignore::IgnoreLine, ignore
+    end
+
+    Steep::AST::Ignore.parse(comments[1], buf).tap do |ignore|
+      assert_instance_of Ignore::IgnoreLine, ignore
+    end
+  end
 end