001    /*
002     $Id: VerifierCodeVisitor.java 4032 2006-08-30 07:18:49Z mguillem $
003    
004     Copyright 2003 (C) James Strachan and Bob Mcwhirter. All Rights Reserved.
005    
006     Redistribution and use of this software and associated documentation
007     ("Software"), with or without modification, are permitted provided
008     that the following conditions are met:
009    
010     1. Redistributions of source code must retain copyright
011        statements and notices.  Redistributions must also contain a
012        copy of this document.
013    
014     2. Redistributions in binary form must reproduce the
015        above copyright notice, this list of conditions and the
016        following disclaimer in the documentation and/or other
017        materials provided with the distribution.
018    
019     3. The name "groovy" must not be used to endorse or promote
020        products derived from this Software without prior written
021        permission of The Codehaus.  For written permission,
022        please contact info@codehaus.org.
023    
024     4. Products derived from this Software may not be called "groovy"
025        nor may "groovy" appear in their names without prior written
026        permission of The Codehaus. "groovy" is a registered
027        trademark of The Codehaus.
028    
029     5. Due credit should be given to The Codehaus -
030        http://groovy.codehaus.org/
031    
032     THIS SOFTWARE IS PROVIDED BY THE CODEHAUS AND CONTRIBUTORS
033     ``AS IS'' AND ANY EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT
034     NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
035     FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL
036     THE CODEHAUS OR ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
037     INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
038     (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
039     SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
040     HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
041     STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
042     ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
043     OF THE POSSIBILITY OF SUCH DAMAGE.
044    
045     */
046    package org.codehaus.groovy.classgen;
047    
048    import java.util.Iterator;
049    import java.util.List;
050    
051    import org.codehaus.groovy.ast.ASTNode;
052    import org.codehaus.groovy.ast.CodeVisitorSupport;
053    import org.codehaus.groovy.ast.stmt.ForStatement;
054    import org.codehaus.groovy.ast.expr.BinaryExpression;
055    import org.codehaus.groovy.ast.expr.Expression;
056    import org.codehaus.groovy.ast.expr.ListExpression;
057    import org.codehaus.groovy.ast.expr.MapEntryExpression;
058    import org.codehaus.groovy.ast.expr.MethodCallExpression;
059    import org.codehaus.groovy.ast.expr.PropertyExpression;
060    import org.codehaus.groovy.ast.expr.FieldExpression;
061    import org.codehaus.groovy.ast.expr.VariableExpression;
062    import org.codehaus.groovy.syntax.RuntimeParserException;
063    import org.objectweb.asm.Opcodes;
064    
065    /**
066     * Verifies the method code
067     * 
068     * @author <a href="mailto:james@coredevelopers.net">James Strachan</a>
069     * @version $Revision: 4032 $
070     */
071    public class VerifierCodeVisitor extends CodeVisitorSupport implements Opcodes {
072    
073        private Verifier verifier;
074    
075        VerifierCodeVisitor(Verifier verifier) {
076            this.verifier = verifier;
077        }
078    
079        public void visitMethodCallExpression(MethodCallExpression call) {
080            super.visitMethodCallExpression(call);
081        }
082    
083        public void visitForLoop(ForStatement expression) {
084            assertValidIdentifier(expression.getVariable().getName(), "for loop variable name", expression);
085            super.visitForLoop(expression);
086        }
087    
088        public void visitPropertyExpression(PropertyExpression expression) {
089            // assertValidIdentifier(expression.getProperty(), "property name", expression);  // This has been commented out to fix the issue Groovy-843
090            super.visitPropertyExpression(expression);
091        }
092    
093        public void visitFieldExpression(FieldExpression expression) {
094            assertValidIdentifier(expression.getFieldName(), "field name", expression);
095            super.visitFieldExpression(expression);
096        }
097    
098        public void visitVariableExpression(VariableExpression expression) {
099            assertValidIdentifier(expression.getName(), "variable name", expression);
100            super.visitVariableExpression(expression);
101        }
102    
103        public void visitBinaryExpression(BinaryExpression expression) {
104            /*
105            if (verifier.getClassNode().isScript() && expression.getOperation().getType() == Token.EQUAL) {
106                // lets turn variable assignments into property assignments
107                Expression left = expression.getLeftExpression();
108                if (left instanceof VariableExpression) {
109                    VariableExpression varExp = (VariableExpression) left;
110    
111                    //System.out.println("Converting variable expression: " + varExp.getVariable());
112    
113                    PropertyExpression propExp =
114                        new PropertyExpression(VariableExpression.THIS_EXPRESSION, varExp.getVariable());
115                    expression.setLeftExpression(propExp);
116                }
117            }
118            */
119            super.visitBinaryExpression(expression);
120        }
121    
122        public static void assertValidIdentifier(String name, String message, ASTNode node) {
123            int size = name.length();
124            if (size <= 0) {
125                throw new RuntimeParserException("Invalid " + message + ". Identifier must not be empty", node);
126            }
127            char firstCh = name.charAt(0);
128            if (!Character.isJavaIdentifierStart(firstCh) || firstCh == '$') {
129                throw new RuntimeParserException("Invalid " + message + ". Must start with a letter but was: " + name, node);
130            }
131    
132            for (int i = 1; i < size; i++) {
133                char ch = name.charAt(i);
134                if (!Character.isJavaIdentifierPart(ch)) {
135                    throw new RuntimeParserException("Invalid " + message + ". Invalid character at position: " + (i + 1) + " of value:  " + ch + " in name: " + name, node);
136                }
137            }
138        }
139        
140        public void visitListExpression(ListExpression expression) {
141            List expressions = expression.getExpressions();
142            for (Iterator iter = expressions.iterator(); iter.hasNext();) {
143                Object element = iter.next();
144                if (element instanceof MapEntryExpression) {
145                    throw new RuntimeParserException ("no map entry allowed at this place",(Expression) element);
146                }
147            }
148            super.visitListExpression(expression);
149        }
150    }