resolves asciidoctor#2034 only indent paragraph that follows an adjac…

…ent paragraph if prose-adjacent-text-indent key is set in theme

CHANGELOG.adoc

@@ -81,6 +81,7 @@ Enhancements::
 * log error and skip table instead of raising error if cell content cannot fit into column width of table (#2009)
 * extract `arrange_section` method to compute whether section title should be advanced to next page (#2023)
 * introduce `callout-list` category in theme to control font properties and item spacing of callout lists (#1722)
+* only indent inner paragraphs (paragraphs that follow an adjacent paragraph) if `prose-inner-text-indent` key is set in theme (#2034)
 
 Bug Fixes::
 

docs/theming-guide.adoc

@@ -2371,10 +2371,17 @@ The bottom margin is only added if the block is followed by an adjacent block wi
 (default: _not set_)
 |prose:
   text-indent: 18
+
+|inner-text-indent^[2]^
+|<<measurement-units,Measurement>> +
+(default: _not set_)
+|prose:
+  inner-text-indent: 18
 |===
 
 1. Controls the margin between adjacent paragraphs.
 Useful when using indented paragraphs.
+2. Only applied to inner paragraphs (paragraphs that follow an adjacent paragraph).
 
 [#keys-block]
 === Block

lib/asciidoctor/pdf/converter.rb

@@ -460,6 +460,7 @@ def prepare_theme theme
         theme.heading_margin_top ||= 0
         theme.heading_margin_bottom ||= 0
         theme.prose_text_indent ||= 0
+        theme.prose_inner_text_indent ||= 0
         theme.prose_margin_bottom ||= 0
         theme.block_margin_bottom ||= 0
         theme.list_indent ||= 0
@@ -813,7 +814,9 @@ def convert_paragraph node
           roles -= TextAlignmentRoles
         end
 
-        if (text_indent = @theme.prose_text_indent) > 0
+        if (text_indent = @theme.prose_text_indent) > 0 ||
+            ((text_indent = @theme.prose_inner_text_indent) > 0 &&
+            (self_idx = (siblings = node.parent.blocks).index node) > 0 && siblings[self_idx - 1].context == :paragraph)
           prose_opts[:indent_paragraphs] = text_indent
         end
 

spec/paragraph_spec.rb

@@ -81,6 +81,32 @@
     (expect (pdf.text[3][:y] - list_item_text[:y]).round 2).to eql 27.78
   end
 
+  it 'should indent first line of inner paragraphs if prose_inner_text_indent key is set in theme' do
+    left_margin = (to_pdf 'text', analyze: true).text[0][:x]
+    pdf_theme = {
+      prose_inner_text_indent: 10.5,
+      prose_margin_inner: 0,
+    }
+    pdf = to_pdf <<~EOS, analyze: true, pdf_theme: pdf_theme
+    #{lorem_ipsum '2-sentences-1-paragraph'}
+
+    #{lorem_ipsum '2-sentences-1-paragraph'}
+
+    > blockquote
+
+    #{lorem_ipsum '2-sentences-1-paragraph'}
+
+    #{lorem_ipsum '2-sentences-1-paragraph'}
+    EOS
+
+    lorem_texts = pdf.find_text %r/^Lorem/
+    (expect lorem_texts).to have_size 4
+    (expect lorem_texts[0][:x]).to eql left_margin
+    (expect lorem_texts[1][:x]).to be > left_margin
+    (expect lorem_texts[2][:x]).to eql left_margin
+    (expect lorem_texts[3][:x]).to be > left_margin
+  end
+
   it 'should allow text alignment to be controlled using text-align document attribute' do
     pdf = to_pdf <<~'EOS', analyze: true
     = Document Title