com.google.errorprone.bugpatterns.flogger.FloggerWithoutCause 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.flogger;
import static com.google.errorprone.matchers.method.MethodMatchers.instanceMethod;
import com.google.common.collect.Lists;
import com.google.errorprone.BugPattern;
import com.google.errorprone.VisitorState;
import com.google.errorprone.bugpatterns.BugChecker;
import com.google.errorprone.fixes.SuggestedFix;
import com.google.errorprone.matchers.Description;
import com.google.errorprone.matchers.Matcher;
import com.google.errorprone.util.ASTHelpers;
import com.sun.source.tree.ExpressionTree;
import com.sun.source.tree.MethodInvocationTree;
import com.sun.source.tree.Tree;
import com.sun.source.util.TreeScanner;
import com.sun.tools.javac.code.Type;
import java.util.concurrent.atomic.AtomicBoolean;
import javax.annotation.Nullable;
import javax.lang.model.type.TypeKind;
/**
* Detects Flogger log statements that pass Exceptions to the log method instead of using withCause.
*/
@BugPattern(
summary = "Use withCause to associate Exceptions with log statements",
severity = BugPattern.SeverityLevel.WARNING)
public class FloggerWithoutCause extends BugChecker
implements BugChecker.MethodInvocationTreeMatcher {
private static final Matcher LOG_METHOD =
instanceMethod().onDescendantOf("com.google.common.flogger.LoggingApi").named("log");
private static final Matcher WITH_CAUSE =
instanceMethod().onDescendantOf("com.google.common.flogger.LoggingApi").named("withCause");
@Override
public Description matchMethodInvocation(MethodInvocationTree tree, VisitorState state) {
if (!LOG_METHOD.matches(tree, state)) {
return Description.NO_MATCH;
}
Tree exception = getExceptionArg(tree, state);
if (exception == null) {
return Description.NO_MATCH;
}
AtomicBoolean withCause = new AtomicBoolean(false);
tree.accept(
new TreeScanner() {
@Override
public Void visitMethodInvocation(MethodInvocationTree tree, Void unused) {
if (WITH_CAUSE.matches(tree, state)) {
withCause.set(true);
}
return super.visitMethodInvocation(tree, null);
}
},
null);
if (withCause.get()) {
return Description.NO_MATCH;
}
return describeMatch(
tree,
SuggestedFix.postfixWith(
ASTHelpers.getReceiver(tree),
String.format(".withCause(%s)", state.getSourceForNode(exception))));
}
@Nullable
private static Tree getExceptionArg(MethodInvocationTree tree, VisitorState state) {
for (Tree arg : Lists.reverse(tree.getArguments())) {
try {
Type argType = ASTHelpers.getType(arg);
if (argType != null
&& argType.getKind() != TypeKind.NULL
&& ASTHelpers.isSubtype(argType, state.getSymtab().throwableType, state)) {
return arg;
}
} catch (RuntimeException t) {
// ignore completion failures
}
}
return null;
}
}