org.antlr.v4.semantics.AttributeChecks Maven / Gradle / Ivy
Go to download
Show more of this group Show more artifacts with this name
Show all versions of antlr4 Show documentation
Show all versions of antlr4 Show documentation
The ANTLR 4 grammar compiler.
/*
* [The "BSD license"]
* Copyright (c) 2012 Terence Parr
* Copyright (c) 2012 Sam Harwell
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. The name of the author may not be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
package org.antlr.v4.semantics;
import org.antlr.runtime.ANTLRStringStream;
import org.antlr.runtime.Token;
import org.antlr.v4.parse.ActionSplitter;
import org.antlr.v4.parse.ActionSplitterListener;
import org.antlr.v4.tool.Alternative;
import org.antlr.v4.tool.ErrorManager;
import org.antlr.v4.tool.ErrorType;
import org.antlr.v4.tool.Grammar;
import org.antlr.v4.tool.LabelElementPair;
import org.antlr.v4.tool.LabelType;
import org.antlr.v4.tool.Rule;
import org.antlr.v4.tool.ast.ActionAST;
import org.antlr.v4.tool.ast.GrammarAST;
import java.util.List;
/** Trigger checks for various kinds of attribute expressions.
* no side-effects.
*/
public class AttributeChecks implements ActionSplitterListener {
public Grammar g;
public Rule r; // null if action outside of rule
public Alternative alt; // null if action outside of alt; could be in rule
public ActionAST node;
public Token actionToken; // token within action
public ErrorManager errMgr;
public AttributeChecks(Grammar g, Rule r, Alternative alt, ActionAST node, Token actionToken) {
this.g = g;
this.r = r;
this.alt = alt;
this.node = node;
this.actionToken = actionToken;
this.errMgr = g.tool.errMgr;
}
public static void checkAllAttributeExpressions(Grammar g) {
for (ActionAST act : g.namedActions.values()) {
AttributeChecks checker = new AttributeChecks(g, null, null, act, act.token);
checker.examineAction();
}
for (Rule r : g.rules.values()) {
for (ActionAST a : r.namedActions.values()) {
AttributeChecks checker = new AttributeChecks(g, r, null, a, a.token);
checker.examineAction();
}
for (int i=1; i<=r.numberOfAlts; i++) {
Alternative alt = r.alt[i];
for (ActionAST a : alt.actions) {
AttributeChecks checker =
new AttributeChecks(g, r, alt, a, a.token);
checker.examineAction();
}
}
for (GrammarAST e : r.exceptions) {
ActionAST a = (ActionAST)e.getChild(1);
AttributeChecks checker = new AttributeChecks(g, r, null, a, a.token);
checker.examineAction();
}
if ( r.finallyAction!=null ) {
AttributeChecks checker =
new AttributeChecks(g, r, null, r.finallyAction, r.finallyAction.token);
checker.examineAction();
}
}
}
public void examineAction() {
//System.out.println("examine "+actionToken);
ANTLRStringStream in = new ANTLRStringStream(actionToken.getText());
in.setLine(actionToken.getLine());
in.setCharPositionInLine(actionToken.getCharPositionInLine());
ActionSplitter splitter = new ActionSplitter(in, this);
// forces eval, triggers listener methods
node.chunks = splitter.getActionTokens();
}
// LISTENER METHODS
@Override
public void setQualifiedAttr(String expr, Token x, Token y, Token rhs) {
qualifiedAttr(expr, x, y);
new AttributeChecks(g, r, alt, node, rhs).examineAction();
}
// $x.y
@Override
public void qualifiedAttr(String expr, Token x, Token y) {
if ( g.isLexer() ) {
errMgr.grammarError(ErrorType.ATTRIBUTE_IN_LEXER_ACTION,
g.fileName, x, x.getText()+"."+y.getText(), expr);
return;
}
if ( node.resolver.resolveToAttribute(x.getText(), node)!=null ) {
// must be a member access to a predefined attribute like $ctx.foo
attr(expr, x);
return;
}
if ( node.resolver.resolveToAttribute(x.getText(), y.getText(), node)==null ) {
Rule rref = isolatedRuleRef(x.getText());
if ( rref!=null ) {
if ( rref.args!=null && rref.args.get(y.getText())!=null ) {
g.tool.errMgr.grammarError(ErrorType.INVALID_RULE_PARAMETER_REF,
g.fileName, y, y.getText(), rref.name, expr);
}
else {
errMgr.grammarError(ErrorType.UNKNOWN_RULE_ATTRIBUTE,
g.fileName, y, y.getText(), rref.name, expr);
}
}
else if ( !node.resolver.resolvesToAttributeDict(x.getText(), node) ) {
errMgr.grammarError(ErrorType.UNKNOWN_SIMPLE_ATTRIBUTE,
g.fileName, x, x.getText(), expr);
}
else {
errMgr.grammarError(ErrorType.UNKNOWN_ATTRIBUTE_IN_SCOPE,
g.fileName, y, y.getText(), expr);
}
}
}
@Override
public void setAttr(String expr, Token x, Token rhs) {
if ( g.isLexer() ) {
errMgr.grammarError(ErrorType.ATTRIBUTE_IN_LEXER_ACTION,
g.fileName, x, x.getText(), expr);
return;
}
if ( node.resolver.resolveToAttribute(x.getText(), node)==null ) {
ErrorType errorType = ErrorType.UNKNOWN_SIMPLE_ATTRIBUTE;
if ( node.resolver.resolvesToListLabel(x.getText(), node) ) {
// $ids for ids+=ID etc...
errorType = ErrorType.ASSIGNMENT_TO_LIST_LABEL;
}
errMgr.grammarError(errorType,
g.fileName, x, x.getText(), expr);
}
new AttributeChecks(g, r, alt, node, rhs).examineAction();
}
@Override
public void attr(String expr, Token x) {
if ( g.isLexer() ) {
errMgr.grammarError(ErrorType.ATTRIBUTE_IN_LEXER_ACTION,
g.fileName, x, x.getText(), expr);
return;
}
if ( node.resolver.resolveToAttribute(x.getText(), node)==null ) {
if ( node.resolver.resolvesToToken(x.getText(), node) ) {
return; // $ID for token ref or label of token
}
if ( node.resolver.resolvesToListLabel(x.getText(), node) ) {
return; // $ids for ids+=ID etc...
}
if ( isolatedRuleRef(x.getText())!=null ) {
errMgr.grammarError(ErrorType.ISOLATED_RULE_REF,
g.fileName, x, x.getText(), expr);
return;
}
errMgr.grammarError(ErrorType.UNKNOWN_SIMPLE_ATTRIBUTE,
g.fileName, x, x.getText(), expr);
}
}
@Override
public void nonLocalAttr(String expr, Token x, Token y) {
Rule r = g.getRule(x.getText());
if ( r==null ) {
errMgr.grammarError(ErrorType.UNDEFINED_RULE_IN_NONLOCAL_REF,
g.fileName, x, x.getText(), y.getText(), expr);
}
else if ( r.resolveToAttribute(y.getText(), null)==null ) {
errMgr.grammarError(ErrorType.UNKNOWN_RULE_ATTRIBUTE,
g.fileName, y, y.getText(), x.getText(), expr);
}
}
@Override
public void setNonLocalAttr(String expr, Token x, Token y, Token rhs) {
Rule r = g.getRule(x.getText());
if ( r==null ) {
errMgr.grammarError(ErrorType.UNDEFINED_RULE_IN_NONLOCAL_REF,
g.fileName, x, x.getText(), y.getText(), expr);
}
else if ( r.resolveToAttribute(y.getText(), null)==null ) {
errMgr.grammarError(ErrorType.UNKNOWN_RULE_ATTRIBUTE,
g.fileName, y, y.getText(), x.getText(), expr);
}
}
@Override
public void text(String text) { }
// don't care
public void templateInstance(String expr) { }
public void indirectTemplateInstance(String expr) { }
public void setExprAttribute(String expr) { }
public void setSTAttribute(String expr) { }
public void templateExpr(String expr) { }
// SUPPORT
public Rule isolatedRuleRef(String x) {
if ( node.resolver instanceof Grammar ) return null;
if ( x.equals(r.name) ) return r;
List labels = null;
if ( node.resolver instanceof Rule ) {
labels = r.getElementLabelDefs().get(x);
}
else if ( node.resolver instanceof Alternative ) {
labels = ((Alternative)node.resolver).labelDefs.get(x);
}
if ( labels!=null ) { // it's a label ref. is it a rule label?
LabelElementPair anyLabelDef = labels.get(0);
if ( anyLabelDef.type==LabelType.RULE_LABEL ) {
return g.getRule(anyLabelDef.element.getText());
}
}
if ( node.resolver instanceof Alternative ) {
if ( ((Alternative)node.resolver).ruleRefs.get(x)!=null ) {
return g.getRule(x);
}
}
return null;
}
}