feat: enable informative (USAGE) checking of SVG content conformance

This commit re-enables SVG content conformance checking:
  * new NVDL and RelaxNG schema drivers will only check SVG content, and ignore other
    namespaces.
  * these informative schemas are enabled for both SVG and XHTML Content Documents
  * SVG content conformance, as before, is using RelaxNG schemas from the Nu HTML Checker.

src/main/java/com/adobe/epubcheck/ops/OPSChecker.java

@@ -56,11 +56,11 @@ public class OPSChecker extends PublicationResourceChecker
       .putAll(Predicates.and(mimetype("application/xhtml+xml"), version(EPUBVersion.VERSION_2)),
           XMLValidators.XHTML_20_NVDL, XMLValidators.XHTML_20_SCH, XMLValidators.IDUNIQUE_20_SCH)
       .putAll(Predicates.and(mimetype("application/xhtml+xml"), version(EPUBVersion.VERSION_3)),
-          XMLValidators.XHTML_30_RNC, XMLValidators.XHTML_30_SCH)
+          XMLValidators.XHTML_30_RNC, XMLValidators.XHTML_30_SCH, XMLValidators.SVG_INFORMATIVE_30_NVDL)
       .putAll(Predicates.and(mimetype("image/svg+xml"), version(EPUBVersion.VERSION_2)),
           XMLValidators.SVG_20_NVDL, XMLValidators.IDUNIQUE_20_SCH)
       .putAll(Predicates.and(mimetype("image/svg+xml"), version(EPUBVersion.VERSION_3)),
-          XMLValidators.SVG_30_NVDL)
+          XMLValidators.SVG_30_NVDL, XMLValidators.SVG_INFORMATIVE_30_NVDL)
       .putAll(
           and(or(profile(EPUBProfile.DICT), hasPubType(OPFData.DC_TYPE_DICT)),
               mimetype("application/xhtml+xml"), version(EPUBVersion.VERSION_3)),

src/main/java/com/adobe/epubcheck/xml/XMLValidators.java

@@ -39,6 +39,7 @@ public enum XMLValidators
   SVG_20_NVDL("schema/20/rng/ops20-svg.nvdl"),
   SVG_30_RNC("schema/30/epub-svg-30.rnc"),
   SVG_30_NVDL("schema/30/epub-svg-30.nvdl"),
+  SVG_INFORMATIVE_30_NVDL("schema/30/epub-svg-informative.nvdl", false),
   SVG_30_SCH("schema/30/epub-svg-30.sch"),
   XHTML_20_NVDL("schema/20/rng/ops20.nvdl"),
   XHTML_20_SCH("schema/20/sch/xhtml.sch"),

src/main/resources/com/adobe/epubcheck/schema/30/epub-svg-informative.nvdl

@@ -0,0 +1,12 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<rules xmlns="http://purl.oclc.org/dsdl/nvdl/ns/structure/1.0">
+	<namespace ns="http://www.w3.org/2000/svg">
+		<validate schema="epub-svg-informative.rnc" schemaType="application/relax-ng-compact-syntax"/>
+	</namespace>
+	<namespace ns="" match="attributes">
+		<attach/>
+	</namespace>
+	<anyNamespace match="elements attributes">
+		<allow/>
+	</anyNamespace>
+</rules>

src/main/resources/com/adobe/epubcheck/schema/30/epub-svg-informative.rnc

@@ -0,0 +1,30 @@
+namespace svg = "http://www.w3.org/2000/svg"
+
+include "./mod/epub-xhtml.rnc" {
+  # This schema applies both to XHTML and SVG documents
+  start = svg | html.elem
+}
+include "./mod/svg11/svg11-inc.rnc" {
+  # ID datatype is set here to the lower HTML requirements,
+  # proper checking is done by the normative schema
+  SVG.id.attrib = attribute id { datatype.html5.token }?
+}
+include "./mod/svg11/inkscape.rnc"
+
+## EPUB-specific additions:
+
+SVG.Core.attrib &= aria.global?
+SVG.Core.extra.attrib &= epub.type.attr?
+
+## Do not check restricted elements, they are checked in normative schemas
+SVG.foreignObject.content |= any.content
+SVG.title.content |= any.content
+
+## Anything
+
+## Any attribute from any namespace, other than the special cases
+any.attr = attribute * { text }*
+## Any element from any namespace, other than the special cases
+any.elem = element * { any.content & any.attr }
+## Any content from any namespace
+any.content = text & any.elem*

src/main/resources/com/adobe/epubcheck/schema/30/epub30-catalog.xml

@@ -18,6 +18,12 @@
    <system systemId="http://www.idpf.org/epub/30/schema/epub-svg-30.sch"
            uri="epub-svg-30.sch"/>
 
+   <system systemId="http://www.idpf.org/epub/30/schema/epub-svg-informative.nvdl"
+           uri="epub-svg-informative.nvdl"/>
+
+   <system systemId="http://www.idpf.org/epub/30/schema/epub-svg-informative.rnc"
+           uri="epub-svg-informative.rnc"/>
+
    <system systemId="http://www.idpf.org/epub/30/schema/epub-xhtml-30.nvdl"
            uri="epub-xhtml-30.nvdl"/>
 

src/test/resources/epub3/content-document-xhtml.feature

@@ -724,8 +724,8 @@ Feature: EPUB 3 ▸ Content Documents ▸ XHTML Document Checks
   Scenario: Verify that SVG validation erors are reported as USAGE
     Given the reporting level set to usage 
     When checking document 'svg-invalid-usage.xhtml'
-    #Then usage SVG-000 is reported 
-    #And the message contains 'element "foo" not allowed here'
+    Then usage RSC-025 is reported 
+    And the message contains 'element "foo" not allowed here'
     And no other errors or warnings are reported
 
   #TODO review if this warning is relevant