regexp: a named character is a character too

RegExpSupport/src/org/intellij/lang/regexp/psi/RegExpChar.java

@@ -18,22 +18,30 @@ package org.intellij.lang.regexp.psi;
 import org.jetbrains.annotations.NotNull;
 
 /**
- * Represents a simple or escaped character
+ * Represents a simple, escaped, encoded or named character
  */
 public interface RegExpChar extends RegExpAtom, RegExpClassElement, RegExpCharRange.Endpoint {
-    /**
-     * Character type enumeration. Represents either a plain character ("a"),
-     * a hex encoded character value ("\x61"),
-     * an octal encoded character value ("\0141"), or
-     * a unicode escape character ("\u0061")
-     */
+    /** Character type */
     enum Type {
-        CHAR, HEX, OCT, UNICODE, INVALID
+        /** a plain character ("a") */
+        CHAR,
+
+        /** a hex encoded character value ("\x61") */
+        HEX,
+
+        /** an octal encoded character value ("\0141") */
+        OCT,
+
+        /** a unicode escape character ("\u0061") */
+        UNICODE,
+
+        /** a named character (\N{LATIN SMALL LETTER A}) */
+        NAMED,
     }
 
     /**
      * Returns the type of this character.
-     * @see org.intellij.lang.regexp.psi.RegExpChar.Type
+     * @see Type
      */
     @NotNull
     Type getType();

RegExpSupport/src/org/intellij/lang/regexp/psi/RegExpElementVisitor.java

@@ -20,6 +20,7 @@ import com.intellij.psi.PsiElementVisitor;
 public class RegExpElementVisitor extends PsiElementVisitor {
 
     public void visitRegExpElement(RegExpElement element) {
+        visitElement(element);
     }
 
     public void visitRegExpChar(RegExpChar ch) {
@@ -51,7 +52,7 @@ public class RegExpElementVisitor extends PsiElementVisitor {
     }
 
     public void visitRegExpNamedCharacter(RegExpNamedCharacter namedCharacter) {
-        visitRegExpElement(namedCharacter);
+        visitRegExpChar(namedCharacter);
     }
 
     public void visitRegExpBranch(RegExpBranch branch) {

RegExpSupport/src/org/intellij/lang/regexp/psi/RegExpNamedCharacter.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2000-2016 JetBrains s.r.o.
+ * Copyright 2000-2017 JetBrains s.r.o.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -21,7 +21,7 @@ import org.jetbrains.annotations.Nullable;
 /**
  * @author Bas Leijdekkers
  */
-public interface RegExpNamedCharacter extends RegExpAtom, RegExpClassElement {
+public interface RegExpNamedCharacter extends RegExpChar {
 
   @Nullable
   ASTNode getNameNode();

RegExpSupport/src/org/intellij/lang/regexp/psi/impl/RegExpCharImpl.java

@@ -17,7 +17,6 @@ package org.intellij.lang.regexp.psi.impl;
 
 import com.intellij.lang.ASTNode;
 import com.intellij.psi.StringEscapesTokenTypes;
-import com.intellij.psi.TokenType;
 import com.intellij.psi.tree.IElementType;
 import com.intellij.psi.tree.TokenSet;
 import org.intellij.lang.regexp.RegExpTT;
@@ -47,8 +46,8 @@ public class RegExpCharImpl extends RegExpElementImpl implements RegExpChar {
             return Type.HEX;
         } else if (UNICODE_CHARS.contains(t)) {
             return Type.UNICODE;
-        } else if (t == TokenType.ERROR_ELEMENT) {
-            return Type.INVALID;
+        } else if (t == RegExpTT.NAMED_CHARACTER) {
+            return Type.NAMED;
         } else {
             return Type.CHAR;
         }
@@ -92,6 +91,15 @@ public class RegExpCharImpl extends RegExpElementImpl implements RegExpChar {
                         return '\b';
                     case 'c':
                         return (char)(ch ^ 64);
+                    case 'N':
+                        if (length < idx + 3 || s.charAt(idx + 1) != '{' || s.charAt(length - 1) != '}') {
+                            return -1;
+                        }
+                        final int codePoint = UnicodeCharacterNames.getCodePoint(s.substring(idx + 2, length - 1));
+                        if (codePoint == -1) {
+                            return -1;
+                        }
+                        return codePoint;
                     case 'x':
                       if (length <= idx + 1) return -1;
                       if (s.charAt(idx + 1) == '{') {

RegExpSupport/src/org/intellij/lang/regexp/psi/impl/RegExpNamedCharacterImpl.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2000-2016 JetBrains s.r.o.
+ * Copyright 2000-2017 JetBrains s.r.o.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -24,7 +24,8 @@ import org.jetbrains.annotations.Nullable;
 /**
  * @author Bas Leijdekkers
  */
-public class RegExpNamedCharacterImpl extends RegExpElementImpl implements RegExpNamedCharacter {
+public class RegExpNamedCharacterImpl extends RegExpCharImpl implements RegExpNamedCharacter {
+
   public RegExpNamedCharacterImpl(ASTNode node) {
     super(node);
   }

RegExpSupport/src/org/intellij/lang/regexp/validation/RegExpAnnotator.java

@@ -477,12 +477,6 @@ public final class RegExpAnnotator extends RegExpElementVisitor implements Annot
       myLength++;
     }
 
-    @Override
-    public void visitRegExpNamedCharacter(RegExpNamedCharacter namedCharacter) {
-      super.visitRegExpNamedCharacter(namedCharacter);
-      myLength++;
-    }
-
     @Override
     public void visitRegExpBackref(RegExpBackref backref) {
       super.visitRegExpBackref(backref);