preprocess second line of setext section title; add test (PR #2321)

3 files changed, 17 insertions, 4 deletions

diff --git a/lib/asciidoctor/parser.rb b/lib/asciidoctor/parser.rb
index 257eb3d8..376e6428 100644
--- a/lib/asciidoctor/parser.rb
+++ b/lib/asciidoctor/parser.rb
@@ -1599,7 +1599,9 @@ class Parser
     if (style = attributes[1]) && (style.start_with? 'discrete', 'float') && (DiscreteHeadingStyleRx.match? style)
       return
     elsif reader.has_more_lines?
-      Compliance.underline_style_section_titles ? is_section_title?(*reader.peek_lines(2, true)) : is_single_line_section_title?(reader.peek_line)
+      Compliance.underline_style_section_titles ?
+          is_section_title?(*reader.peek_lines(2, style ? style == 'comment' : false)) :
+          is_single_line_section_title?(reader.peek_line)
     end
   end
 
diff --git a/test/blocks_test.rb b/test/blocks_test.rb
index cb03e25a..37690f5c 100644
--- a/test/blocks_test.rb
+++ b/test/blocks_test.rb
@@ -198,9 +198,9 @@ line should not be rendered
       assert_xpath '//p', output, 0
     end
 
-    # WARNING if first line of content is a directive, it will get interpretted before we know it's a comment block
-    # it happens because we always look a line ahead...not sure what we can do about it
-    test 'preprocessor directives should not be processed within comment paragraph' do
+    # WARNING this assertion fails if the directive is the first line of the paragraph instead of the second
+    # it happens because we always look a line ahead; not sure what we can do about it
+    test 'preprocessor directives should not be processed on subsequent lines of a comment paragraph' do
       input = <<-EOS
 [comment]
 first line of content
diff --git a/test/sections_test.rb b/test/sections_test.rb
index fc1c2994..1825abfb 100644
--- a/test/sections_test.rb
+++ b/test/sections_test.rb
@@ -396,6 +396,17 @@ My Section
       assert_includes result, '----^^----'
     end
 
+    test 'should preprocess second line of setext section title' do
+      input = <<-EOS
+Section Title
+ifdef::asciidoctor[]
+-------------
+endif::[]
+      EOS
+      result = render_embedded_string input
+      assert_xpath '//h2', result, 1
+    end
+
     test "heading title with multiline syntax cannot begin with a dot" do
       title = ".My Title"
       chars = "-" * title.length