resolves #1983 prevent scientific notation ending up in generated PDF…

… (PR #1984)

CHANGELOG.adoc

@@ -12,6 +12,10 @@ Enhancements::
 * show URL of link for any media type when show-link-uri is set (#951)
 * do not show URL of link when media type is screen or prepress when show-link-uri is unset (#951)
 
+Bug Fixes::
+
+* update patches for `PDF::Core.real` and `PDF::Core.real_params` to prevent scientific notation ending up in PDF (#1983) (@rillbert)
+
 == 1.6.1 (2021-09-04) - @mojavelinux
 
 Enhancements::

lib/asciidoctor/pdf/ext/pdf-core.rb

@@ -3,13 +3,15 @@
 module PDF::Core
   class << self
     alias _initial_real real
-    def real num
-      num.to_f.round 4
+
+    # NOTE Makes v1.6.x work with the modified precision settings (0.5f) in Prawn 2.4 while preserving existing behavior
+    def real num, precision = 4
+      ("%.#{precision}f" % num).sub(/((?<!\.)0)+\z/, '')
     end
 
     alias _initial_real_params real_params
     def real_params array
-      return array.map {|it| it.to_f.round 5 }.join ' ' if (caller_locations 1, 1)[0].base_label == 'transformation_matrix'
+      return array.map {|e| real e, 5 }.join(' ') if (caller_locations 1, 1)[0].base_label == 'transformation_matrix'
       _initial_real_params array
     end
   end

spec/image_spec.rb

@@ -244,6 +244,12 @@
       (expect to_file).to visually_match 'image-svg-scale-to-fit-bounds.pdf'
     end
 
+    it 'should output fixed precision numbers even when set width differs to viewBox with small amount', visual: true do
+      to_file = to_pdf_file 'image::green-bar-width-diff.svg[]', 'image-svg-fixed-precision.pdf'
+
+      (expect to_file).to visually_match 'image-svg-fixed-precision.pdf'
+    end
+
     it 'should display text inside link' do
       pdf = to_pdf <<~'EOS', analyze: true
       image::svg-with-link.svg[]