com.google.errorprone.bugpatterns.UnnecessaryMethodInvocationMatcher Maven / Gradle / Ivy
/*
* Copyright 2019 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.WARNING;
import static com.google.errorprone.matchers.Description.NO_MATCH;
import static com.google.errorprone.matchers.Matchers.staticMethod;
import com.google.errorprone.BugPattern;
import com.google.errorprone.VisitorState;
import com.google.errorprone.bugpatterns.BugChecker.MethodInvocationTreeMatcher;
import com.google.errorprone.fixes.SuggestedFix;
import com.google.errorprone.matchers.Description;
import com.google.errorprone.matchers.Matcher;
import com.google.errorprone.matchers.Matchers;
import com.google.errorprone.matchers.method.MethodMatchers.MethodMatcher;
import com.google.errorprone.util.ASTHelpers;
import com.sun.source.tree.ExpressionTree;
import com.sun.source.tree.MethodInvocationTree;
import com.sun.tools.javac.code.Type;
import java.util.List;
/**
* {@link Matchers#methodInvocation(Matcher)} is not exactly deprecated, but it is legacy, and in
* particular is not needed when the argument is a MethodMatcher, since MethodMatcher already does
* the unwrapping that methodInvocation does.
*
* @author [email protected] (Alan Malloy)
*/
@BugPattern(
name = "UnnecessaryMethodInvocationMatcher",
summary = "It is not necessary to wrap a MethodMatcher with methodInvocation().",
severity = WARNING)
public class UnnecessaryMethodInvocationMatcher extends BugChecker
implements MethodInvocationTreeMatcher {
private static final String MATCHERS = Matchers.class.getCanonicalName();
private static final Matcher METHOD_INVOCATION =
staticMethod().onClass(MATCHERS).named("methodInvocation");
private static final Matcher COMBINATOR =
staticMethod().onClass(MATCHERS).namedAnyOf("allOf", "anyOf", "not");
@Override
public Description matchMethodInvocation(MethodInvocationTree tree, VisitorState state) {
if (!METHOD_INVOCATION.matches(tree, state)) {
return NO_MATCH;
}
List arguments = tree.getArguments();
if (arguments.size() != 1) {
// We can only unwrap if they haven't specified additional behavior.
return NO_MATCH;
}
Type methodMatcherType = state.getTypeFromString(MethodMatcher.class.getCanonicalName());
ExpressionTree argument = arguments.get(0);
if (!containsOnlyMethodMatchers(argument, methodMatcherType, state)) {
return NO_MATCH;
}
return describeMatch(tree, SuggestedFix.replace(tree, state.getSourceForNode(argument)));
}
private static boolean containsOnlyMethodMatchers(
ExpressionTree expressionTree, Type methodMatcherType, VisitorState state) {
if (ASTHelpers.isSubtype(ASTHelpers.getType(expressionTree), methodMatcherType, state)) {
return true;
}
if (!COMBINATOR.matches(expressionTree, state)) {
return false;
}
for (ExpressionTree argument : ((MethodInvocationTree) expressionTree).getArguments()) {
if (!containsOnlyMethodMatchers(argument, methodMatcherType, state)) {
return false;
}
}
return true;
}
}