resolves asciidoctor#3602 move abstract inside info tag in DocBook ou…

…tput

CHANGELOG.adoc

@@ -69,6 +69,7 @@ Bug Fixes::
 
   * Preserve paragraph breaks in normal table cell in manpage output (#4481)
   * Escape spaces in include target (using inline passthrough) when generating link from include directive (#4461)
+  * Move abstract to info in DocBook output (#3602)
 
 == 2.0.20 (2023-05-18) - @mojavelinux
 

lib/asciidoctor/converter/docbook5.rb

@@ -45,7 +45,8 @@ def convert_document node
     end
     root_tag_idx = result.size
     id = node.id
-    result << (document_info_tag node) unless node.noheader
+    abstract = extract_abstract node
+    result << (document_info_tag node, abstract) unless node.noheader
     if manpage
       result << '<refentry>'
       result << '<refmeta>'
@@ -71,6 +72,7 @@ def convert_document node
     # defer adding root tag in case document ID is auto-generated on demand
     result.insert root_tag_idx, %(<#{root_tag_name} xmlns="http://docbook.org/ns/docbook" xmlns:xl="http://www.w3.org/1999/xlink" version="5.0"#{lang_attribute}#{common_attributes id}>)
     result << %(</#{root_tag_name}>)
+    abstract.parent.blocks.insert 0, abstract if abstract
     result.join LF
   end
 
@@ -365,6 +367,7 @@ def convert_paragraph node
   end
 
   def convert_preamble node
+    return unless node.blocks?
     if node.document.doctype == 'book'
       %(<preface#{common_attributes node.id, node.role, node.reftext}>
 #{title_tag node, false}#{node.content}
@@ -663,7 +666,7 @@ def author_tag doc, author
     result.join LF
   end
 
-  def document_info_tag doc
+  def document_info_tag doc, abstract
     result = ['<info>']
     unless doc.notitle
       if (title = doc.doctitle partition: true, use_fallback: true).subtitle?
@@ -717,11 +720,24 @@ def document_info_tag doc
         result << docinfo_content
       end
     end
+    result << (convert_open abstract) if abstract
     result << '</info>'
 
     result.join LF
   end
 
+  def extract_abstract doc
+    return unless doc.blocks? && (first_block = doc.blocks[0]).context != :section
+    if first_block.context == :open
+      if first_block.style == 'abstract'
+        (abstract = first_block).parent.blocks.delete_at 0
+      end
+    elsif first_block.context == :preamble && (first_block = first_block.blocks[0]) && first_block.style == 'abstract' && first_block.context == :open
+      (abstract = first_block).parent.blocks.delete_at 0
+    end
+    abstract
+  end
+
   def get_root_document node
     while (node = node.document).nested?
       node = node.parent_document

test/blocks_test.rb

@@ -3681,8 +3681,8 @@ def names
       EOS
 
       output = convert_string input, backend: 'docbook'
-      assert_css 'abstract', output, 1
-      assert_css 'abstract > simpara', output, 2
+      assert_css 'info > abstract', output, 1
+      assert_css 'info > abstract > simpara', output, 2
     end
 
     test 'should make abstract on open block with title converted to DocBook' do
@@ -3697,9 +3697,9 @@ def names
       EOS
 
       output = convert_string input, backend: 'docbook'
-      assert_css 'abstract', output, 1
-      assert_css 'abstract > title', output, 1
-      assert_css 'abstract > title + simpara', output, 1
+      assert_css 'info > abstract', output, 1
+      assert_css 'info > abstract > title', output, 1
+      assert_css 'info > abstract > title + simpara', output, 1
     end
 
     test 'should allow abstract in document with title if doctype is book converted to DocBook' do
@@ -3712,7 +3712,8 @@ def names
       EOS
 
       output = convert_string input, backend: 'docbook'
-      assert_css 'abstract', output, 1
+      assert_css 'info > abstract', output, 1
+      assert_css 'preface', output, 0
     end
 
     test 'should not allow abstract as direct child of document if doctype is book converted to DocBook' do