feat: re-implement relevant checks from the ctc package in core handlers

src/main/java/com/adobe/epubcheck/messages/DefaultSeverities.java

@@ -324,7 +324,7 @@ private void initialize()
     severities.put(MessageId.RSC_015, Severity.ERROR);
     severities.put(MessageId.RSC_016, Severity.FATAL);
     severities.put(MessageId.RSC_017, Severity.WARNING);
-    severities.put(MessageId.RSC_018, Severity.WARNING);
+    severities.put(MessageId.RSC_018, Severity.SUPPRESSED); // Reported as RSC-007
     severities.put(MessageId.RSC_019, Severity.WARNING);
     severities.put(MessageId.RSC_020, Severity.ERROR);
     severities.put(MessageId.RSC_021, Severity.ERROR);

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

@@ -212,6 +212,9 @@ else if (".".equals(href))
         }
       }
     }
+    if ("file".equals(uri.getScheme())) {
+      report.message(MessageId.HTM_053, parser.getLocation(), uri);
+    }
 
     /*
      * mgy 20120417 adding check for base to initial if clause as part of

src/main/java/com/adobe/epubcheck/ops/OPSHandler30.java

@@ -3,6 +3,7 @@
 import java.util.Collections;
 import java.util.EnumSet;
 import java.util.HashSet;
+import java.util.List;
 import java.util.Locale;
 import java.util.Map;
 import java.util.Set;
@@ -43,6 +44,7 @@
 import com.adobe.epubcheck.xml.XMLElement;
 import com.adobe.epubcheck.xml.XMLParser;
 import com.google.common.base.Joiner;
+import com.google.common.base.Splitter;
 import com.google.common.base.Strings;
 import com.google.common.collect.ImmutableMap;
 import com.google.common.collect.ImmutableSet;
@@ -63,6 +65,8 @@ public class OPSHandler30 extends OPSHandler
   private static Map<String, Vocab> KNOWN_VOCAB_URIS = ImmutableMap.of(MagazineNavigationVocab.URI,
       MagazineNavigationVocab.VOCAB, ForeignVocabs.PRISM_URI, ForeignVocabs.PRISM_VOCAB);
   private static Set<String> DEFAULT_VOCAB_URIS = ImmutableSet.of(StructureVocab.URI);
+
+  private static final Splitter TOKENIZER = Splitter.onPattern("\\s+").omitEmptyStrings();
 
   private Map<String, Vocab> vocabs = RESERVED_VOCABS;
 
@@ -87,6 +91,7 @@ public class OPSHandler30 extends OPSHandler
   protected boolean isOutermostSVGAlreadyProcessed = false;
   protected boolean hasAltorAnnotation = false;
   protected boolean hasTitle = false;
+  protected boolean hasViewport = false;
 
   static protected final String[] scriptEventsStrings = { "onafterprint", "onbeforeprint",
       "onbeforeunload", "onerror", "onhaschange", "onload", "onmessage", "onoffline", "onpagehide",
@@ -312,6 +317,9 @@ public void startElement()
           KNOWN_VOCAB_URIS, DEFAULT_VOCAB_URIS, report,
           EPUBLocation.create(path, parser.getLineNumber(), parser.getColumnNumber()));
     }
+    else if (EpubConstants.HtmlNamespaceUri.equals(e.getNamespace()) && name.equals("meta")) {
+      processMeta(e);
+    }
     else if (name.equals("link"))
     {
       processLink(e);
@@ -325,6 +333,11 @@ else if (name.equals("math"))
       requiredProperties.add(ITEM_PROPERTIES.MATHML);
       inMathML = true;
       hasAltorAnnotation = (null != e.getAttribute("alttext"));
+      String altimg = e.getAttribute("altimg");
+      if (altimg != null) {
+        super.checkImage(e, null, "altimg");
+      }
+
     }
     else if (name.equals("svg"))
     {
@@ -679,6 +692,31 @@ else if (!isOutermostSVGAlreadyProcessed)
     }
   }
 
+  protected void processMeta(XMLElement e)
+  {
+    if (EpubConstants.HtmlNamespaceUri.equals(e.getNamespace()))
+    {
+      String name = e.getAttribute("name");
+      if ("viewport".equals(name))
+      {
+        hasViewport = true;
+        // For a fixed-layout document:
+        // check that the vieport declares both height and width
+        if (context.opfItem.isPresent() && context.opfItem.get().isFixedLayout())
+        {
+          String contentAttribute = e.getAttribute("content");
+          if (contentAttribute == null || !contentAttribute.contains("width=")
+              || !contentAttribute.contains("height="))
+          {
+            report.message(MessageId.HTM_047,
+                EPUBLocation.create(path, parser.getLineNumber(), parser.getColumnNumber()));
+          }
+        }
+      }
+    }
+  }
+
+
   protected void processTable(XMLElement e)
   {
     context.featureReport.report(FeatureEnum.TABLE, parser.getLocation());
@@ -802,6 +840,9 @@ else if (name.equals("svg"))
     {
       inSvg = false;
     }
+    else if (EpubConstants.HtmlNamespaceUri.equals(e.getNamespace()) && name.equals("head")) {
+      checkHead();
+    }
   }
 
   /*
@@ -859,4 +900,31 @@ protected void checkProperties()
           .join(PackageVocabs.ITEM_VOCAB.getNames(uncheckedProperties)));
     }
   }
+
+  protected void checkHead()
+  {
+    if (context.opfItem.isPresent() && context.opfItem.get().isFixedLayout() && !hasViewport)
+    {
+      report.message(MessageId.HTM_046,
+          EPUBLocation.create(path, parser.getLineNumber(), parser.getColumnNumber()));
+    }
+  }
+
+  @Override
+  protected void checkLink(XMLElement e, String attrNS, String attr)
+  {
+    super.checkLink(e, attrNS, attr);
+    String rel = e.getAttributeNS(attrNS, "rel");
+    if (rel != null)
+    {
+      String title = e.getAttributeNS(attrNS, "title");
+      List<String> linkTypes = TOKENIZER.splitToList(rel);
+      if (linkTypes.contains("alternate") && linkTypes.contains("stylesheet")
+          && Strings.isNullOrEmpty(title))
+      {
+        report.message(MessageId.CSS_015,
+            EPUBLocation.create(path, parser.getLineNumber(), parser.getColumnNumber()));
+      }
+    }
+  }
 }

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

@@ -242,6 +242,11 @@ Feature: EPUB 3 ▸ Content Documents ▸ XHTML Document Checks
     When checking document 'link-rel-stylesheet-alternate-valid.xhtml'
     Then no errors or warnings are reported
 
+  Scenario: Report `link` element defining an alternative stylesheet with no title
+    When checking document 'link-rel-stylesheet-alternate-no-title-error.xhtml'
+    Then error CSS-015 is reported 2 times (one for a missing title, one for an empty title)
+    And no other errors or warnings are reported
+
 
   ####  Lists
 

src/test/resources/epub3/content-publication.feature

@@ -182,7 +182,7 @@ Feature: EPUB 3 ▸ Content Documents ▸ Full Publication Checks
 
   Scenario: Report a MathML formula with an alternative image that cannot be found
     When checking EPUB 'content-xhtml-mathml-altimg-not-found-warning'
-    Then warning RSC-018 is reported
+    Then error RSC-007 is reported
     And no other errors or warnings are reported
 
 

src/test/resources/epub3/files/content-document-xhtml/link-rel-stylesheet-alternate-no-title-error.xhtml

@@ -0,0 +1,12 @@
+<!DOCTYPE html>
+<html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en" lang="en">
+	<head>
+		<meta charset="utf-8" />
+		<title>Test</title>
+		<link href="tite-empty.css" rel="alternate stylesheet" type="text/css" title="" />
+		<link href="title-missing.css" rel="alternate stylesheet" type="text/css" />
+	</head>
+	<body>
+		<h1>Test</h1>
+	</body>
+</html>