/*
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance
* with the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing,
* software distributed under the License is distributed on an
* "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
* KIND, either express or implied. See the License for the
* specific language governing permissions and limitations
* under the License.
*/
package org.apache.groovy.parser.antlr4;
import org.antlr.v4.runtime.CharStream;
import org.antlr.v4.runtime.Token;
import org.antlr.v4.runtime.TokenStream;
import java.util.Collections;
import java.util.Set;
import static org.apache.groovy.parser.antlr4.GroovyParser.*;
/**
* Some semantic predicates for altering the behaviour of the lexer and parser
*
* @author <a href="mailto:realbluesun@hotmail.com">Daniel.Sun</a>
* Created on 2016/08/20
*/
public class SemanticPredicates {
public static boolean isFollowedByWhiteSpaces(CharStream cs) {
for (int index = 1, c = cs.LA(index); !('\r' == c || '\n' == c || CharStream.EOF == c); index++, c = cs.LA(index)) {
if (String.valueOf((char) c).matches("\\S+?")) {
return false;
}
}
return true;
}
public static boolean isFollowedBy(CharStream cs, char... chars) {
int c1 = cs.LA(1);
for (char c : chars) {
if (c1 == c) {
return true;
}
}
return false;
}
public static boolean isFollowedByJavaLetterInGString(CharStream cs) {
int c1 = cs.LA(1);
if ('$' == c1) { // single $ is not a valid identifier
return false;
}
String str1 = String.valueOf((char) c1);
if (str1.matches("[a-zA-Z_{]")) {
return true;
}
if (str1.matches("[^\u0000-\u007F\uD800-\uDBFF]")
&& Character.isJavaIdentifierPart(c1)) {
return true;
}
int c2 = cs.LA(2);
String str2 = String.valueOf((char) c2);
if (str1.matches("[\uD800-\uDBFF]")
&& str2.matches("[\uDC00-\uDFFF]")
&& Character.isJavaIdentifierPart(Character.toCodePoint((char) c1, (char) c2))) {
return true;
}
return false;
}
/**
* Check whether following a method name of command expression.
* Method name should not end with "2: arguments" and "3: closure"
*
* @param t the type of pathExpression
* @return
*/
public static boolean isFollowingMethodName(int t) {
return !(2 == t || 3 == t);
}
/**
* Distinguish between method declaration and method call/constructor declaration
*/
public static boolean isInvalidMethodDeclaration(TokenStream ts) {
int tokenType = ts.LT(1).getType();
return (Identifier == tokenType || CapitalizedIdentifier == tokenType || StringLiteral == tokenType)
&& LPAREN == (ts.LT(2).getType());
}
private static final Set<Integer> MODIFIER_SET =
Collections.unmodifiableSet(ModifierNode.MODIFIER_OPCODE_MAP.keySet());
/**
* Distinguish between local variable declaration and method call, e.g. `a b`
*/
public static boolean isInvalidLocalVariableDeclaration(TokenStream ts) {
int index = 2;
Token token;
int tokenType;
int tokenType2 = ts.LT(index).getType();
int tokenType3;
if (DOT == tokenType2) {
int tokeTypeN = tokenType2;
do {
index = index + 2;
tokeTypeN = ts.LT(index).getType();
} while (DOT == tokeTypeN);
if (LT == tokeTypeN || LBRACK == tokeTypeN) {
return false;
}
index = index - 1;
tokenType2 = ts.LT(index + 1).getType();
} else {
index = 1;
}
token = ts.LT(index);
tokenType = token.getType();
tokenType3 = ts.LT(index + 2).getType();
return //VOID == tokenType ||
!(BuiltInPrimitiveType == tokenType || MODIFIER_SET.contains(tokenType))
&& Character.isLowerCase(token.getText().codePointAt(0))
&& !(ASSIGN == tokenType3 || (LT == tokenType2 || LBRACK == tokenType2));
}
}