com.google.errorprone.bugpatterns.ExtendingJUnitAssert Maven / Gradle / Ivy
/*
* Copyright 2018 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.Matchers.staticMethod;
import com.google.errorprone.BugPattern;
import com.google.errorprone.VisitorState;
import com.google.errorprone.bugpatterns.BugChecker.ClassTreeMatcher;
import com.google.errorprone.fixes.SuggestedFix;
import com.google.errorprone.matchers.Description;
import com.google.errorprone.matchers.Matcher;
import com.google.errorprone.suppliers.Supplier;
import com.google.errorprone.util.ASTHelpers;
import com.google.errorprone.util.ErrorProneToken;
import com.sun.source.tree.ClassTree;
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 com.sun.tools.javac.parser.Tokens.TokenKind;
import java.util.List;
/**
* @author [email protected] (Kayla Walker)
*/
@BugPattern(
summary =
"When only using JUnit Assert's static methods, "
+ "you should import statically instead of extending.",
severity = WARNING)
public class ExtendingJUnitAssert extends BugChecker implements ClassTreeMatcher {
private static final Matcher STATIC_ASSERT =
staticMethod().onClass("org.junit.Assert").withAnyName();
@Override
public Description matchClass(ClassTree tree, VisitorState state) {
Tree extendsClause = tree.getExtendsClause();
Type type = ASTHelpers.getType(extendsClause);
if (ASTHelpers.isSameType(type, ORG_JUNIT_ASSERT.get(state), state)) {
return describeMatch(extendsClause, fixAsserts(tree, state));
}
return Description.NO_MATCH;
}
private SuggestedFix fixAsserts(ClassTree tree, VisitorState state) {
SuggestedFix.Builder fix = SuggestedFix.builder();
tree.accept(
new TreeScanner() {
@Override
public Void visitMethodInvocation(MethodInvocationTree tree, Void unused) {
if (STATIC_ASSERT.matches(tree, state)) {
String assertType = ASTHelpers.getSymbol(tree).getSimpleName().toString();
fix.addStaticImport("org.junit.Assert." + assertType);
}
return super.visitMethodInvocation(tree, unused);
}
},
null);
Tree extendsClause = tree.getExtendsClause();
int endOfExtendsClause = state.getEndPosition(extendsClause);
List tokens = state.getOffsetTokensForNode(tree);
int startPos = 0;
for (ErrorProneToken token : tokens) {
if (token.pos() > endOfExtendsClause) {
break;
}
if (token.kind() == TokenKind.EXTENDS) {
int curr = token.pos();
if (curr > startPos) {
startPos = curr;
}
}
}
return fix.replace(startPos, endOfExtendsClause, "").build();
}
private static final Supplier ORG_JUNIT_ASSERT =
VisitorState.memoize(state -> state.getTypeFromString("org.junit.Assert"));
}