fix: allow ARIA headings in EDUPUB (legacy profile)

rdeltour · rdeltour · commit da4f5412ee5e · 2023-04-22T01:11:44.000+02:00
This commit fixes the legacy EDUPUB checks by allowing ARIA headings along with native h1-h6 headings. Note: EDUPUB support is a legacy feature of EPUBCheck, since the standard is not actively maintained. Fix #1483
diff --git a/src/main/resources/com/adobe/epubcheck/schema/30/edupub/edu-structure.sch b/src/main/resources/com/adobe/epubcheck/schema/30/edupub/edu-structure.sch
@@ -2,92 +2,148 @@
 <schema xmlns="https://purl.oclc.org/dsdl/schematron" queryBinding="xslt2">
 	<ns uri="https://www.idpf.org/2007/ops" prefix="epub"/>
 	<ns uri="https://www.w3.org/1999/xhtml" prefix="html"/>
-	
+
 	<!-- following variable declarations are used to test h# nesting depth -->
 	<!-- checks if the body contains anything other than a single section or article - i.e., is it an implied section 
 		- previously tested if >1 article/section children with : or count(//html:body/child::html:*[self::html:article or self::html:section]) &gt; 1
 		  but ambiguous whether multiple section elements is an implied body or just a weird breakup of the file
 	-->
-	<let name="body-is-section" value="exists(//html:body/(html:* except (html:article|html:section)))"/>
-	
+	<let name="body-is-section"
+		value="exists(//html:body/(html:* except (html:article | html:section)))"/>
+
 	<!-- check if implied heading -->
 	<let name="body-label-len" value="string-length(normalize-space(//html:body/@aria-label))"/>
-	
+
 	<!-- finds the topmost heading in the file that is the descendant of the body (not sectioning element ancestors) or the first descendant of a section or article -->
-	<let name="topmost-heading" value="//html:body//(html:h1|html:h2|html:h3|html:h4|html:h5|html:h6)[not(ancestor::html:aside|ancestor::html:nav) and count(ancestor::html:section|ancestor::html:article) le 1]"/>
-	
+	<let name="topmost-heading"
+		value="//html:body//(html:h1 | html:h2 | html:h3 | html:h4 | html:h5 | html:h6 | html:*[@role = 'heading'])[not(ancestor::html:aside | ancestor::html:nav) and count(ancestor::html:section | ancestor::html:article) le 1]"/>
+
 	<!-- extract the starting rank from the topmost-heading -->
-	<let name="topmost-heading-rank" value="if ($body-label-len &gt; 0) then 1 else if (exists($topmost-heading)) then number(substring(name($topmost-heading[1]),2)) else 1"/>
-	
+	<let name="topmost-heading-rank" value="
+			if ($body-label-len &gt; 0) then
+				1
+			else
+				if (exists($topmost-heading)) then
+					if ($topmost-heading[1][@role = 'heading']) then
+						if ($topmost-heading[1]/@aria-level) then
+							number($topmost-heading[1]/@aria-level)
+						else
+							2
+					else
+						number(substring(name($topmost-heading[1]), 2))
+				else
+					1"/>
+
 	<!-- find the nesting depth of the topmost heading (0 if body, 1 if a section or article around it) -->
-	<let name="topmost-heading-nest" value="if ($body-label-len &gt; 0) then 0 else if (empty($topmost-heading[1]/(ancestor::html:section|ancestor::html:article|ancestor::html:nav))) then 0 else 1"/>
-	
-	
+	<let name="topmost-heading-nest" value="
+			if ($body-label-len &gt; 0) then
+				0
+			else
+				if (empty($topmost-heading[1]/(ancestor::html:section | ancestor::html:article | ancestor::html:nav))) then
+					0
+				else
+					1"/>
+
+
 	<pattern id="edupub.headings">
-		<rule context="html:body[html:* except (html:article|html:section|html:aside|html:nav)]">
-			<let name="headings" value=".//(html:h1|html:h2|html:h3|html:h4|html:h5|html:h6)[empty(ancestor::html:section|ancestor::html:aside|ancestor::html:article|ancestor::html:nav)]"/>
-			
+		<rule context="html:body[html:* except (html:article | html:section | html:aside | html:nav)]">
+			<let name="headings"
+				value=".//(html:h1 | html:h2 | html:h3 | html:h4 | html:h5 | html:h6 | html:*[@role = 'heading'])[empty(ancestor::html:section | ancestor::html:aside | ancestor::html:article | ancestor::html:nav)]"/>
+
 			<report test="@aria-label and $body-label-len = 0">Empty aria-label attribute found.</report>
-			
-			<assert test="$body-label-len &gt; 0 or count($headings) &gt; 0">The body element requires a heading when it is used as an implied section.</assert>
-			
+
+			<assert test="$body-label-len &gt; 0 or count($headings) &gt; 0">The body element requires a
+				heading when it is used as an implied section.</assert>
+
 			<!-- <report test="$arialabel-len &gt; 0 and count($headings) &gt; 0">The aria-label attribute must not be mixed with ranked headings.</report> -->
-			
-			<report test="count($headings) &gt; 1">More than one ranked heading found as direct descendant of body.</report>
-			
-			<report test="count($headings) = 1 and string-length(normalize-space(string-join($headings|$headings/html:img/@alt|$headings//@aria-label))) = 0">Empty ranked heading detected.</report>
-			
-			<report test="@aria-label and (normalize-space($headings) = normalize-space(@aria-label))">The value of the "aria-label" attribute must not be the same as the content of the heading.</report>
+
+			<report test="count($headings) &gt; 1">More than one ranked heading found as direct descendant
+				of body.</report>
+
+			<report
+				test="count($headings) = 1 and string-length(normalize-space(string-join($headings | $headings/html:img/@alt | $headings//@aria-label))) = 0"
+				>Empty ranked heading detected.</report>
+
+			<report test="@aria-label and (normalize-space($headings) = normalize-space(@aria-label))">The
+				value of the "aria-label" attribute must not be the same as the content of the
+				heading.</report>
 		</rule>
-		
-		
-		<rule context="html:section|html:article">
+
+
+		<rule context="html:section | html:article">
 			<let name="arialabel-len" value="string-length(normalize-space(@aria-label))"/>
-			<let name="headings" value=".//(html:h1|html:h2|html:h3|html:h4|html:h5|html:h6)[(ancestor::html:section|ancestor::html:article|ancestor::html:aside|ancestor::html:nav)[last()] = current()]"/>
-			
+			<let name="headings"
+				value=".//(html:h1 | html:h2 | html:h3 | html:h4 | html:h5 | html:h6 | html:*[@role = 'heading'])[(ancestor::html:section | ancestor::html:article | ancestor::html:aside | ancestor::html:nav)[last()] = current()]"/>
+
 			<report test="@aria-label and $arialabel-len = 0">Empty aria-label attribute found.</report>
-			
-			<assert test="$arialabel-len &gt; 0 or count($headings) &gt; 0"><value-of select="name()"/> does not have a heading.</assert>
-			
+
+			<assert test="$arialabel-len &gt; 0 or count($headings) &gt; 0"><value-of select="name()"/>
+				does not have a heading.</assert>
+
 			<!-- <report test="$arialabel-len &gt; 0 and count($headings) &gt; 0">The aria-label attribute must not be mixed with ranked headings.</report> -->
-			
-			<report test="count($headings) &gt; 1">More than one ranked heading found as direct descendant of <value-of select="name()"/>.</report>
-			
-			<report test="count($headings) = 1 and string-length(normalize-space(string-join($headings|$headings/html:img/@alt|$headings//@aria-label))) = 0">Empty ranked heading detected.</report>
-			
-			<report test="@aria-label and (normalize-space($headings) = normalize-space(@aria-label))">The value of the "aria-label" attribute must not be the same as the content of the heading.</report>
+
+			<report test="count($headings) &gt; 1">More than one ranked heading found as direct descendant
+				of <value-of select="name()"/>.</report>
+
+			<report
+				test="count($headings) = 1 and string-length(normalize-space(string-join($headings | $headings/html:img/@alt | $headings//@aria-label))) = 0"
+				>Empty ranked heading detected.</report>
+
+			<report test="@aria-label and (normalize-space($headings) = normalize-space(@aria-label))">The
+				value of the "aria-label" attribute must not be the same as the content of the
+				heading.</report>
 		</rule>
-		
-		<rule context="html:h1|html:h2|html:h3|html:h4|html:h5|html:h6">
+
+		<rule
+			context="html:h1 | html:h2 | html:h3 | html:h4 | html:h5 | html:h6 | html:*[@role = 'heading']">
 			<!-- get the # from the h# tag found -->
-			<let name="current-rank" value="number(substring(name(current()),2))"/>
-			
+			<let name="current-rank" value="
+					if (current()[@role = 'heading']) then
+						if (current()/@aria-level) then
+							number(current()/@aria-level)
+						else
+							2
+					else
+						number(substring(name(current()), 2))"/>
+
 			<!-- find nesting depth -->
-			<let name="current-nesting" value="count(ancestor::html:section|ancestor::html:article|ancestor::html:aside|ancestor::html:nav)"/>
-			
+			<let name="current-nesting"
+				value="count(ancestor::html:section | ancestor::html:article | ancestor::html:aside | ancestor::html:nav)"/>
+
 			<!-- derive the expected rank of this heading from the implied body or sectioning -->
-			<let name="expected-rank" value="if ($body-is-section) then $topmost-heading-rank - $topmost-heading-nest + $current-nesting else $topmost-heading-rank + $current-nesting - 1"/>
-			
+			<let name="expected-rank" value="
+					if ($body-is-section) then
+						$topmost-heading-rank - $topmost-heading-nest + $current-nesting
+					else
+						$topmost-heading-rank + $current-nesting - 1"/>
+
 			<!-- report ranked headings in sectioning roots -->
-			<report test="ancestor::html:figure or ancestor::html:blockquote">Ranked headings are not valid in figure or blockquote</report>
-			
+			<report test="ancestor::html:figure or ancestor::html:blockquote">Ranked headings are not
+				valid in figure or blockquote</report>
+
 			<!-- if the expected rank is below 6, check that it matches what is expected -->
-			<report test="$expected-rank &lt; 6 and not($current-rank = $expected-rank)">The heading rank h<value-of select="$current-rank"/> does not match the current nesting level (<value-of select="$expected-rank"/>).</report>
-			
+			<report test="$expected-rank &lt; 6 and not($current-rank = $expected-rank)">The heading rank
+					h<value-of select="$current-rank"/> does not match the current nesting level (<value-of
+					select="$expected-rank"/>).</report>
+
 			<!-- otherwise, just stop testing after 5 and report any headings that aren't six, since no higher exist -->
-			<report test="$expected-rank &gt; 5 and $current-rank &lt; 6">The current heading rank should be h6.</report>
+			<report test="$expected-rank &gt; 5 and $current-rank &lt; 6">The current heading rank should
+				be h6.</report>
 		</rule>
 	</pattern>
-	
+
 	<pattern id="edupub.sectioning">
 		<rule context="*[parent::html:body or parent::html:section][not(self::html:section)]">
-			<report test="preceding-sibling::html:section">Non-section elements not allowed between or after section elements.</report>
+			<report test="preceding-sibling::html:section">Non-section elements not allowed between or
+				after section elements.</report>
 		</rule>
 	</pattern>
-	
+
 	<pattern id="edupub.subtitles">
-		<rule context="html:p[@epub:type='subtitle'][preceding-sibling::*[self::html:h1|self::html:h2|self::html:h3|self::html:h4|self::html:h5|self::html:h6]]">
-			<assert test="ancestor::html:header">Section subtitles must be wrapped in a header element.</assert>
+		<rule
+			context="html:p[@epub:type = 'subtitle'][preceding-sibling::*[self::html:h1 | self::html:h2 | self::html:h3 | self::html:h4 | self::html:h5 | self::html:h6]]">
+			<assert test="ancestor::html:header">Section subtitles must be wrapped in a header
+				element.</assert>
 		</rule>
 	</pattern>
 </schema>
diff --git a/src/test/resources/epub-edupub/edupub-content-document-xhtml.feature b/src/test/resources/epub-edupub/edupub-content-document-xhtml.feature
@@ -41,6 +41,25 @@ Feature: EPUB for Education ▸ XHTML Content Document Checks
     And the message contains 'The body element requires a heading when it is used as an implied section'
     And no other errors or warnings are reported
 
+  Scenario: Report a missing section heading
+    When checking document 'edupub-heading-missing-error.xhtml'
+    Then error RSC-005 is reported
+    And the message contains 'section does not have a heading'
+    But no other errors or warnings are reported
+
+  Scenario: Allow a section heading specified as ARIA heading role
+    When checking document 'edupub-heading-aria-role-valid.xhtml'
+    Then no errors or warnings are reported
+    
+  Scenario: Verify a heading with only an `img` that has alternative text
+    When checking document 'edupub-heading-img-alt-valid.xhtml'
+    Then no errors or warnings are reported
+
+  Scenario: Report a heading with only an `img` without alternative text
+    When checking document 'edupub-heading-img-no-alt-error.xhtml'
+    Then error RSC-005 is reported
+    And the message contains 'Empty ranked heading detected'
+    And no other errors or warnings are reported
 
   ##  4.3 Titles and Headings
   
@@ -84,15 +103,3 @@ Feature: EPUB for Education ▸ XHTML Content Document Checks
     And no other errors or warnings are reported
 
 
-  #  No matching section
-
-  Scenario: Verify a heading with only an `img` that has alternative text
-    When checking document 'edupub-heading-img-alt-valid.xhtml'
-    Then no errors or warnings are reported
-
-  Scenario: Report a heading with only an `img` without alternative text
-    When checking document 'edupub-heading-img-no-alt-error.xhtml'
-    Then error RSC-005 is reported
-    And the message contains 'Empty ranked heading detected'
-    And no other errors or warnings are reported
-
diff --git a/src/test/resources/epub-edupub/files/content-document-xhtml/edupub-heading-aria-role-valid.xhtml b/src/test/resources/epub-edupub/files/content-document-xhtml/edupub-heading-aria-role-valid.xhtml
@@ -0,0 +1,12 @@
+<!DOCTYPE html>
+<html xmlns="https://www.w3.org/1999/xhtml" xml:lang="en" lang="en">
+    <head>
+        <title>Test</title>
+        <meta charset="UTF-8" />
+    </head>
+    <body>
+    	<section>
+    	    <span aria-level="1" role="heading">Heading</span>
+    	</section>
+    </body>
+</html>
diff --git a/src/test/resources/epub-edupub/files/content-document-xhtml/edupub-heading-missing-error.xhtml b/src/test/resources/epub-edupub/files/content-document-xhtml/edupub-heading-missing-error.xhtml
@@ -0,0 +1,12 @@
+<!DOCTYPE html>
+<html xmlns="https://www.w3.org/1999/xhtml" xml:lang="en" lang="en">
+    <head>
+        <title>Test</title>
+        <meta charset="UTF-8" />
+    </head>
+    <body>
+    	<section>
+    		<!--<h1>Test</h1>-->
+    	</section>
+    </body>
+</html>
