com.google.errorprone.bugpatterns.TypeToString Maven / Gradle / Ivy
/*
* Copyright 2020 The Error Prone Authors.
*
* 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 com.google.errorprone.bugpatterns;
import static com.google.errorprone.BugPattern.SeverityLevel.SUGGESTION;
import static com.google.errorprone.matchers.Matchers.instanceMethod;
import static com.google.errorprone.matchers.Matchers.toType;
import static com.google.errorprone.predicates.TypePredicates.isDescendantOf;
import static com.google.errorprone.util.ASTHelpers.isBugCheckerCode;
import com.google.errorprone.BugPattern;
import com.google.errorprone.VisitorState;
import com.google.errorprone.fixes.Fix;
import com.google.errorprone.matchers.Matcher;
import com.google.errorprone.predicates.TypePredicate;
import com.sun.source.tree.ExpressionTree;
import com.sun.source.tree.MemberSelectTree;
import com.sun.source.tree.Tree;
import com.sun.tools.javac.code.Type;
import java.util.Optional;
/**
* Flags {@code com.sun.tools.javac.code.Type#toString} usage in {@link BugChecker}s.
*
* @author [email protected] (Sumit Bhagwani)
*/
@BugPattern(
name = "TypeToString",
summary = "Type#toString shouldn't be used for comparison as it is expensive and fragile.",
severity = SUGGESTION)
public class TypeToString extends AbstractToString {
private static final TypePredicate IS_TYPE = isDescendantOf("com.sun.tools.javac.code.Type");
private static final Matcher STRING_EQUALS =
toType(
MemberSelectTree.class,
instanceMethod().onExactClass("java.lang.String").named("equals"));
private static boolean typeToStringInBugChecker(Type type, VisitorState state) {
if (!isBugCheckerCode(state)) {
return false;
}
Tree parentTree = state.getPath().getParentPath().getLeaf();
return IS_TYPE.apply(type, state) && STRING_EQUALS.matches(parentTree, state);
}
@Override
protected TypePredicate typePredicate() {
return TypeToString::typeToStringInBugChecker;
}
@Override
protected Optional descriptionMessageForDefaultMatch(Type type, VisitorState state) {
return Optional.of("Type#toString shouldn't be used as it is expensive and fragile.");
}
@Override
protected Optional implicitToStringFix(ExpressionTree tree, VisitorState state) {
return Optional.empty();
}
@Override
protected Optional toStringFix(Tree parent, ExpressionTree tree, VisitorState state) {
return Optional.empty();
}
}