/*
* Copyright (C) 2009-2010 Mathias Doenitz
*
* Licensed 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.parboiled.errors;
import org.parboiled.common.Formatter;
import org.parboiled.common.StringUtils;
import org.parboiled.matchers.AnyOfMatcher;
import org.parboiled.matchers.Matcher;
import org.parboiled.support.MatcherPath;
import java.util.ArrayList;
import java.util.List;
/**
* A {@link Formatter} for {@link InvalidInputError}s that automatically creates the correct "expected" text
* for the error.
*/
public class DefaultInvalidInputErrorFormatter implements Formatter<InvalidInputError> {
public String format(InvalidInputError error) {
if (error == null) return "";
String errorMessage = String.format("Invalid input '%s%s'", StringUtils.escape(String.valueOf(
error.getInputBuffer().charAt(error.getStartIndex()))),
error.getEndIndex() - error.getStartIndex() > 1 ? "..." : ""
);
String expectedString = getExpectedString(error);
return StringUtils.isEmpty(expectedString) ? errorMessage : errorMessage + ", expected " + expectedString;
}
public String getExpectedString(InvalidInputError error) {
// In non recovery-mode there is no complexity in the error and start indices since they are all stable.
// However, in recovery-mode the RecoveringParseRunner inserts characters into the InputBuffer, which requires
// for all indices taken before to be shifted. The RecoveringParseRunner does this by changing the indexDelta
// of the parse runner. All users of the ParseError will then automatically see shifted start and end indices
// matching the state of the underlying InputBuffer. However, since the failed MatcherPaths still carry the
// "original" indices we need to unapply the IndexDelta in order to be able to compare with them.
int pathStartIndex = error.getStartIndex() - error.getIndexDelta();
List<String> labelList = new ArrayList<String>();
for (MatcherPath path : error.getFailedMatchers()) {
Matcher labelMatcher = ErrorUtils.findProperLabelMatcher(path, pathStartIndex);
if (labelMatcher == null) continue;
String[] labels = getLabels(labelMatcher);
for (String label : labels) {
if (label != null && !labelList.contains(label)) {
labelList.add(label);
}
}
}
return join(labelList);
}
/**
* Gets the labels corresponding to the given matcher, AnyOfMatchers are treated specially in that their
* label is constructed as a list of their contents
*
* @param matcher the matcher
* @return the labels
*/
public String[] getLabels(Matcher matcher) {
if (matcher instanceof AnyOfMatcher) {
AnyOfMatcher cMatcher = (AnyOfMatcher) matcher;
if (!cMatcher.characters.isSubtractive()) {
String[] labels = new String[cMatcher.characters.getChars().length];
for (int i = 0; i < labels.length; i++) {
labels[i] = '\'' + String.valueOf(cMatcher.characters.getChars()[i]) + '\'';
}
return labels;
}
}
return new String[] {matcher.getLabel()};
}
public String join(List<String> labelList) {
StringBuilder sb = new StringBuilder();
for (int i = 0; i < labelList.size(); i++) {
if (i > 0) sb.append(i < labelList.size() - 1 ? ", " : " or ");
sb.append(labelList.get(i));
}
return StringUtils.escape(sb.toString());
}
}