IDEA-51134: Refactor / rename could work for JSP taglib prefix

xml/impl/src/com/intellij/codeInsight/daemon/impl/analysis/XmlUnboundNsPrefixInspection.java

@@ -116,7 +116,7 @@ public class XmlUnboundNsPrefixInspection extends XmlSuppressableInspectionTool
     if (!HighlightLevelUtil.shouldInspect(containingFile)) return;
 
     final XmlExtension extension = XmlExtension.getExtension(containingFile);
-    if (extension.isPrefixDeclared(context, namespacePrefix)) {
+    if (extension.getPrefixDeclaration(context, namespacePrefix) != null) {
       return;
     }
 

xml/impl/src/com/intellij/psi/impl/source/xml/SchemaPrefix.java

@@ -20,6 +20,7 @@ import com.intellij.psi.impl.RenameableFakePsiElement;
 import com.intellij.psi.search.LocalSearchScope;
 import com.intellij.psi.search.SearchScope;
 import com.intellij.psi.xml.XmlAttribute;
+import com.intellij.psi.xml.XmlFile;
 import com.intellij.util.Icons;
 import org.jetbrains.annotations.NotNull;
 
@@ -73,6 +74,7 @@ public class SchemaPrefix extends RenameableFakePsiElement {
   @NotNull
   @Override
   public SearchScope getUseScope() {
-    return new LocalSearchScope(getDeclaration().getParent());
+    XmlAttribute declaration = getDeclaration();
+    return new LocalSearchScope(declaration.isNamespaceDeclaration() ? declaration.getParent() : ((XmlFile)declaration.getContainingFile()).getDocument());
   }
 }

xml/impl/src/com/intellij/psi/impl/source/xml/SchemaPrefixReference.java

@@ -19,12 +19,13 @@ import com.intellij.openapi.util.NullableLazyValue;
 import com.intellij.openapi.util.TextRange;
 import com.intellij.psi.PsiElement;
 import com.intellij.psi.PsiReferenceBase;
-import com.intellij.psi.xml.XmlAttribute;
-import com.intellij.psi.xml.XmlElement;
-import com.intellij.psi.xml.XmlTag;
+import com.intellij.psi.search.LocalSearchScope;
+import com.intellij.psi.search.SearchScope;
+import com.intellij.psi.util.PsiTreeUtil;
+import com.intellij.psi.xml.*;
 import com.intellij.util.ArrayUtil;
 import com.intellij.util.IncorrectOperationException;
-import com.intellij.xml.util.XmlUtil;
+import com.intellij.xml.XmlExtension;
 import org.jetbrains.annotations.NotNull;
 
 /**
@@ -35,16 +36,26 @@ public class SchemaPrefixReference extends PsiReferenceBase<XmlElement> {
   private final NullableLazyValue<SchemaPrefix> myPrefix = new NullableLazyValue<SchemaPrefix>() {
     @Override
     protected SchemaPrefix compute() {
-      if (myElement instanceof XmlAttribute && ((XmlAttribute)myElement).isNamespaceDeclaration()) {
+      if (myElement instanceof XmlAttribute && (((XmlAttribute)myElement).isNamespaceDeclaration())) {
         return new SchemaPrefix((XmlAttribute)myElement, getRangeInElement(), myName);
       }
+      else if (myElement instanceof XmlAttributeValue &&
+               ((XmlAttribute)((XmlAttributeValue)myElement).getParent()).getLocalName().equals("prefix")) {
+        return new SchemaPrefix((XmlAttribute)myElement.getParent(), getRangeInElement().shiftRight(myElement.getStartOffsetInParent()), myName) {
+          @NotNull
+          @Override
+          public SearchScope getUseScope() {
+            return new LocalSearchScope(((XmlFile)myElement.getContainingFile()).getDocument());
+          }
+        };
+      }
       else {
-        final PsiElement declaration = XmlUtil.findNamespaceDeclaration(myElement, myName);
-        if (declaration instanceof XmlAttribute) {
-          final XmlAttribute attribute = (XmlAttribute)declaration;
-          final String prefix = attribute.getNamespacePrefix();
+        XmlExtension extension = XmlExtension.getExtension(myElement.getContainingFile());
+        final XmlAttribute declaration = extension.getPrefixDeclaration(PsiTreeUtil.getParentOfType(myElement, XmlTag.class, false), myName);
+        if (declaration != null) {
+          final String prefix = declaration.getNamespacePrefix();
           final TextRange textRange = TextRange.from(prefix.length() + 1, myName.length());
-          return new SchemaPrefix(attribute, textRange, myName);
+          return new SchemaPrefix(declaration, textRange, myName);
         }
       }
       return null;
@@ -56,7 +67,6 @@ public class SchemaPrefixReference extends PsiReferenceBase<XmlElement> {
   public SchemaPrefixReference(XmlElement element, TextRange range, String name) {
     super(element, range, true);
     myName = name;
-
   }
 
   public String getNamespacePrefix() {

xml/impl/src/com/intellij/xml/DefaultXmlExtension.java

@@ -242,15 +242,16 @@ public class DefaultXmlExtension extends XmlExtension {
     }
   }
 
-  public boolean isPrefixDeclared(final XmlTag context, String namespacePrefix) {
+  public XmlAttribute getPrefixDeclaration(final XmlTag context, String namespacePrefix) {
     @NonNls String nsDeclarationAttrName = null;
     for(XmlTag t = context; t != null; t = t.getParentTag()) {
       if (t.hasNamespaceDeclarations()) {
         if (nsDeclarationAttrName == null) nsDeclarationAttrName = namespacePrefix.length() > 0 ? "xmlns:"+namespacePrefix:"xmlns";
-        if (t.getAttributeValue(nsDeclarationAttrName) != null) return true;
+        XmlAttribute attribute = t.getAttribute(nsDeclarationAttrName);
+        if (attribute != null) return attribute;
       }
     }
-    return false;
+    return null;
   }
 
   private static Set<String> guessNamespace(final PsiFile file, String tagName) {

xml/impl/src/com/intellij/xml/XmlExtension.java

@@ -153,7 +153,8 @@ public abstract class XmlExtension {
     return HighlightInfoType.ERROR;
   }
 
-  public abstract boolean isPrefixDeclared(final XmlTag context, String namespacePrefix);
+  @Nullable
+  public abstract XmlAttribute getPrefixDeclaration(final XmlTag context, String namespacePrefix);
 
   public boolean shouldBeHighlightedAsTag(XmlTag tag) {
     return true;