resolves #1246 don't crash when adding indentation guards to source highlighted with Pygments (PR #1248)

3 files changed, 31 insertions, 9 deletions

diff --git a/CHANGELOG.adoc b/CHANGELOG.adoc
index 14a8acea..2a4e0bde 100644
--- a/CHANGELOG.adoc
+++ b/CHANGELOG.adoc
@@ -8,6 +8,7 @@ For a detailed view of what has changed, refer to the {uri-repo}/commits/master[
 == Unreleased
 
 * allow font catalog and font fallbacks to be defined as flat keys in the theme file (#1243)
+* don't crash when adding indentation guards to source highlighted with Pygments (#1246)
 
 == 1.5.0.beta.3 (2019-08-30) - @mojavelinux
 
diff --git a/lib/asciidoctor-pdf/converter.rb b/lib/asciidoctor-pdf/converter.rb
index c848a157..9a36a096 100644
--- a/lib/asciidoctor-pdf/converter.rb
+++ b/lib/asciidoctor-pdf/converter.rb
@@ -1808,8 +1808,7 @@ class Converter < ::Prawn::Document
     # append conums to appropriate lines, then flatten to an array of fragments
     lines.flat_map.with_index do |line, cur_line_num|
       last_line = cur_line_num == last_line_num
-      # NOTE use ::String.new to ensure string is not frozen
-      line.unshift text: (::String.new %(#{(cur_line_num + linenums).to_s.rjust pad_size} )), color: linenum_color if linenums
+      line.unshift text: %(#{(cur_line_num + linenums).to_s.rjust pad_size} ), color: linenum_color if linenums
       if (conums = conum_mapping.delete cur_line_num)
         line << { text: ' ' * num_trailing_spaces } if last_line && num_trailing_spaces > 0
         conum_text = conums.map {|num| conum_glyph num }.join ' '
@@ -3480,10 +3479,10 @@ class Converter < ::Prawn::Document
     arranger = ::Prawn::Text::Formatted::Arranger.new self
     by_line = arranger.consumed = []
     fragments.each do |fragment|
-      if (txt = fragment[:text]) == LF
+      if (text = fragment[:text]) == LF
         by_line << fragment
-      elsif txt.include? LF
-        txt.scan(LineScanRx) do |line|
+      elsif text.include? LF
+        text.scan(LineScanRx) do |line|
           by_line << (line == LF ? { text: LF } : (fragment.merge text: line))
         end
       else
@@ -3576,8 +3575,11 @@ class Converter < ::Prawn::Document
     start_of_line = true
     fragments.each do |fragment|
       next if (text = fragment[:text]).empty?
-      text[0] = GuardedIndent if start_of_line && (text.start_with? ' ')
-      text.gsub! InnerIndent, GuardedInnerIndent if text.include? InnerIndent
+      if start_of_line && (text.start_with? ' ')
+        fragment[:text] = GuardedIndent + (((text = text.slice 1, text.length).include? InnerIndent) ? (text.gsub InnerIndent, GuardedInnerIndent) : text)
+      elsif text.include? InnerIndent
+        fragment[:text] = text.gsub InnerIndent, GuardedInnerIndent
+      end
       start_of_line = text.end_with? LF
     end
     fragments
diff --git a/spec/source_spec.rb b/spec/source_spec.rb
index 38c7e49e..16fd5e76 100644
--- a/spec/source_spec.rb
+++ b/spec/source_spec.rb
@@ -142,7 +142,7 @@ describe 'Asciidoctor::PDF::Converter - Source' do
   end
 
   context 'Pygments' do
-    it 'should highlight source using CodeRay if source-highlighter is coderay' do
+    it 'should highlight source using Pygments if source-highlighter is pygments' do
       pdf = to_pdf <<~'EOS', analyze: true
       :source-highlighter: pygments
 
@@ -158,9 +158,28 @@ describe 'Asciidoctor::PDF::Converter - Source' do
       (expect hello_text[:font_name]).to eql 'mplus1mn-regular'
     end
 
+    it 'should not crash when adding indentation guards' do
+      (expect {
+        pdf = to_pdf <<~EOS, analyze: true
+        :source-highlighter: pygments
+
+        [source,yaml]
+        ---
+        category:
+          hash:
+            key: "value"
+        ---
+        EOS
+        (expect pdf.find_text 'category:').to have_size 1
+        (expect pdf.find_text %(\u00a0 hash:)).to have_size 1
+        (expect pdf.find_text %(\u00a0   key: )).to have_size 1
+        (expect pdf.find_text '"value"').to have_size 1
+      }).not_to raise_exception
+    end
+
     it 'should not crash when aligning line numbers' do
       (expect {
-        to_pdf <<~'EOS', analyze: true
+        to_pdf <<~'EOS'
         :source-highlighter: pygments
 
         [source,xml,linenums]