Implement choice for name classes on attributes

https://bugzilla.gnome.org/show_bug.cgi?id=710744

relaxng.c

@@ -9047,6 +9047,19 @@ xmlRelaxNGAttributeMatch(xmlRelaxNGValidCtxtPtr ctxt,
                 return (ret);
             list = list->next;
         }
+    } else if (define->type == XML_RELAXNG_CHOICE) {
+        xmlRelaxNGDefinePtr list;
+
+        list = define->nameClass;
+        while (list != NULL) {
+            ret = xmlRelaxNGAttributeMatch(ctxt, list, prop);
+            if (ret == 1)
+                return (1);
+            if (ret < 0)
+                return (ret);
+            list = list->next;
+        }
+        return (0);
     } else {
     TODO}
     return (1);

result/relaxng/710744_1.err

@@ -0,0 +1 @@
+./test/relaxng/710744_1.xml validates

result/relaxng/710744_2.err

@@ -0,0 +1,2 @@
+./test/relaxng/710744_2.xml:3: element test: Relax-NG validity error : Invalid attribute foo for element test
+./test/relaxng/710744_2.xml fails to validate

test/relaxng/710744.rng

@@ -0,0 +1,16 @@
+<?xml version="1.0"?>
+<grammar xmlns="http://relaxng.org/ns/structure/1.0">
+  <start>
+    <element name="test" ns="http://example.com/1/">
+      <zeroOrMore>
+        <attribute>
+          <choice>
+            <nsName ns="http://example.com/1/"/>
+            <nsName ns="http://example.com/2/"/>
+          </choice>
+          <text/>
+        </attribute>
+      </zeroOrMore>
+    </element>
+  </start>
+</grammar>

test/relaxng/710744_1.xml

@@ -0,0 +1,2 @@
+<ex1:test xmlns:ex1="http://example.com/1/"
+          ex1:foo="bar"/>

test/relaxng/710744_2.xml

@@ -0,0 +1,3 @@
+<ex1:test xmlns:ex1="http://example.com/1/"
+          xmlns:ex3="http://example.com/3/"
+          ex3:foo="bar"/>