resolves #4552 add support for scaledwidth and scale attributes on in…

…line image macro in DocBook output (PR #4554)

CHANGELOG.adoc

@@ -42,6 +42,7 @@ Compliance::
   * Turn off system-dependent newline conversion when writing files; don't convert line feeds to system-dependent newline (#4550)
   * Support logger in Ruby 3.3 by instantiating super class (#4493) (*@mtasaka*)
   * Don't promote level-0 special section at start of document to document title (#4151)
+  * Add support for `scaledwidth` and `scale` attributes on inline image macro in DocBook output (#4552)
   * Disallow the use of dot (`.`) in the name of a named element attribute (#4147)
   * Disallow the use of the left square bracket in an attribute list on formatted text (#4306)
   * Update stylesheet to use break-after in place of page-break-before/after/inside (#3466)

lib/asciidoctor/converter/docbook5.rb

@@ -195,27 +195,11 @@ def convert_floating_title node
   end
 
   def convert_image node
-    # NOTE according to the DocBook spec, content area, scaling, and scaling to fit are mutually exclusive
-    # See http://tdg.docbook.org/tdg/4.5/imagedata-x.html#d0e79635
-    if node.attr? 'scaledwidth'
-      width_attribute = %( width="#{node.attr 'scaledwidth'}")
-      depth_attribute = ''
-      scale_attribute = ''
-    elsif node.attr? 'scale'
-      # QUESTION should we set the viewport using width and depth? (the scaled image would be contained within this box)
-      #width_attribute = (node.attr? 'width') ? %( width="#{node.attr 'width'}") : ''
-      #depth_attribute = (node.attr? 'height') ? %( depth="#{node.attr 'height'}") : ''
-      scale_attribute = %( scale="#{node.attr 'scale'}")
-    else
-      width_attribute = (node.attr? 'width') ? %( contentwidth="#{node.attr 'width'}") : ''
-      depth_attribute = (node.attr? 'height') ? %( contentdepth="#{node.attr 'height'}") : ''
-      scale_attribute = ''
-    end
     align_attribute = (node.attr? 'align') ? %( align="#{node.attr 'align'}") : ''
 
     mediaobject = %(<mediaobject>
 <imageobject>
-<imagedata fileref="#{node.image_uri node.attr 'target'}"#{width_attribute}#{depth_attribute}#{scale_attribute}#{align_attribute}/>
+<imagedata fileref="#{node.image_uri node.attr 'target'}"#{image_size_attributes node.attributes}#{align_attribute}/>
 </imageobject>
 <textobject><phrase>#{node.alt}</phrase></textobject>
 </mediaobject>)
@@ -553,11 +537,9 @@ def convert_inline_footnote node
   end
 
   def convert_inline_image node
-    width_attribute = (node.attr? 'width') ? %( contentwidth="#{node.attr 'width'}") : ''
-    depth_attribute = (node.attr? 'height') ? %( contentdepth="#{node.attr 'height'}") : ''
     %(<inlinemediaobject#{common_attributes nil, node.role}>
 <imageobject>
-<imagedata fileref="#{node.type == 'icon' ? (node.icon_uri node.target) : (node.image_uri node.target)}"#{width_attribute}#{depth_attribute}/>
+<imagedata fileref="#{node.type == 'icon' ? (node.icon_uri node.target) : (node.image_uri node.target)}"#{image_size_attributes node.attributes}/>
 </imageobject>
 <textobject><phrase>#{node.alt}</phrase></textobject>
 </inlinemediaobject>)
@@ -665,6 +647,23 @@ def common_attributes id, role = nil, reftext = nil
     end
   end
 
+  def image_size_attributes attributes
+    # NOTE according to the DocBook spec, content area, scaling, and scaling to fit are mutually exclusive
+    # See http://tdg.docbook.org/tdg/4.5/imagedata-x.html#d0e79635
+    if attributes.key? 'scaledwidth'
+      %( width="#{attributes['scaledwidth']}")
+    elsif attributes.key? 'scale'
+      # QUESTION should we set the viewport using width and depth? (the scaled image would be contained within this box)
+      #width_attribute = (attributes.key? 'width') ? %( width="#{attributes['width']}") : ''
+      #depth_attribute = (attributes.key? 'height') ? %( depth="#{attributes['height']}") : ''
+      %( scale="#{attributes['scale']}")
+    else
+      width_attribute = (attributes.key? 'width') ? %( contentwidth="#{attributes['width']}") : ''
+      depth_attribute = (attributes.key? 'height') ? %( contentdepth="#{attributes['height']}") : ''
+      %(#{width_attribute}#{depth_attribute})
+    end
+  end
+
   def author_tag doc, author
     result = []
     result << '<author>'
@@ -785,26 +784,18 @@ def title_tag node, optional = true
 
   def cover_tag doc, face, use_placeholder = false
     if (cover_image = doc.attr %(#{face}-cover-image))
-      width_attr = ''
-      depth_attr = ''
       if (cover_image.include? ':') && ImageMacroRx =~ cover_image
-        attrlist = $2
-        cover_image = doc.image_uri $1
-        if attrlist
-          attrs = (AttributeList.new attrlist).parse %w(alt width height)
-          if attrs.key? 'scaledwidth'
-            # NOTE scalefit="1" is the default in this case
-            width_attr = %( width="#{attrs['scaledwidth']}")
-          else
-            width_attr = %( contentwidth="#{attrs['width']}") if attrs.key? 'width'
-            depth_attr = %( contentdepth="#{attrs['height']}") if attrs.key? 'height'
-          end
-        end
+        target, attrlist = $1, $2
+        cover_image = doc.image_uri target
+        # NOTE scalefit="1" is the default for a cover image
+        size_attrs = image_size_attributes (AttributeList.new attrlist).parse %w(alt width height) if attrlist
+      else
+        size_attrs = ''
       end
       %(<cover role="#{face}">
 <mediaobject>
 <imageobject>
-<imagedata fileref="#{cover_image}"#{width_attr}#{depth_attr}/>
+<imagedata fileref="#{cover_image}"#{size_attrs}/>
 </imageobject>
 </mediaobject>
 </cover>)

test/substitutions_test.rb

@@ -849,6 +849,18 @@
         para.sub_macros(para.source).gsub(/>\s+</, '><')
     end
 
+    test 'a single-line image macro with scaledwidth attribute should be supported in docbook' do
+      para = block_from_string 'image:tiger.png[Tiger,scaledwidth=25%]', backend: 'docbook'
+      assert_equal '<inlinemediaobject><imageobject><imagedata fileref="tiger.png" width="25%"/></imageobject><textobject><phrase>Tiger</phrase></textobject></inlinemediaobject>',
+        para.sub_macros(para.source).gsub(/>\s+</, '><')
+    end
+
+    test 'a single-line image macro with scaled attribute should be supported in docbook' do
+      para = block_from_string 'image:tiger.png[Tiger,scale=200]', backend: 'docbook'
+      assert_equal '<inlinemediaobject><imageobject><imagedata fileref="tiger.png" scale="200"/></imageobject><textobject><phrase>Tiger</phrase></textobject></inlinemediaobject>',
+        para.sub_macros(para.source).gsub(/>\s+</, '><')
+    end
+
     test 'should pass through role on image macro to DocBook output' do
       para = block_from_string 'image:tiger.png[Tiger,200,role=animal]', backend: 'docbook'
       result = para.sub_macros para.source