[ruby/erb] Fix line numbers after multi-line <%#

(https://github.com/ruby/erb/pull/42)

https://github.com/ruby/erb/commit/526885923e

lib/erb/compiler.rb

@@ -384,7 +384,7 @@ class ERB::Compiler # :nodoc:
     when '<%='
       add_insert_cmd(out, content)
     when '<%#'
-      # commented out
+      out.push("\n" * content.count("\n")) # only adjust lineno
     end
   end
 

test/erb/test_erb.rb

@@ -713,6 +713,18 @@ EOS
     erb = Marshal.load(Marshal.dump(erb))
     assert_raise(ArgumentError) {erb.result}
   end
+
+  def test_multi_line_comment_lineno
+    erb = ERB.new(<<~EOS)
+      <%= __LINE__ %>
+      <%#
+      %><%= __LINE__ %>
+    EOS
+    assert_equal <<~EOS, erb.result
+      1
+      3
+    EOS
+  end
 end
 
 class TestERBCoreWOStrScan < TestERBCore