/*
* Copyright 2014 Google Inc. All Rights Reserved.
*
* 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.matchers;
import static org.junit.Assert.assertTrue;
import com.google.errorprone.Scanner;
import com.google.errorprone.VisitorState;
import com.sun.source.tree.ExpressionTree;
import com.sun.source.tree.MethodInvocationTree;
import org.junit.Test;
import org.junit.runner.RunWith;
import org.junit.runners.JUnit4;
/**
* @author deminguyen@google.com (Demi Nguyen)
*/
@RunWith(JUnit4.class)
public class MethodReturnsNonNullNextTokenTest extends CompilerBasedAbstractTest {
@Test
public void shouldMatch() {
writeFile("A.java",
"import java.util.StringTokenizer;",
"public class A {",
" public void testNextToken() {",
" StringTokenizer st = new StringTokenizer(\"test string\");",
" st.nextToken();",
" }",
"}"
);
assertCompiles(methodInvocationMatches(true, Matchers.methodReturnsNonNull()));
}
@Test
public void shouldNotMatchOtherMethod() {
writeFile("A.java",
"import java.util.StringTokenizer;",
"public class A {",
" public void testOtherMethod() {",
" StringTokenizer st = new StringTokenizer(\"test string\");",
" st.hasMoreTokens();",
" }",
"}"
);
assertCompiles(methodInvocationMatches(false, Matchers.methodReturnsNonNull()));
}
@Test
public void shouldNotMatchOverridenMethod() {
writeFile("A.java",
"import java.util.StringTokenizer;",
"public class A extends StringTokenizer {",
" public A(String str, String delim, boolean returnDelims) {",
" super(str, delim, returnDelims);",
" }",
" @Override",
" public String nextToken() {",
" return \"overridden method\";",
" }",
" public void testOverridenNextToken() {",
" nextToken();",
" }",
"}"
);
assertCompiles(methodInvocationMatches(false, Matchers.methodReturnsNonNull()));
}
private Scanner methodInvocationMatches(
final boolean shouldMatch, final Matcher<ExpressionTree> toMatch) {
return new Scanner() {
@Override
public Void visitMethodInvocation(MethodInvocationTree node, VisitorState visitorState) {
ExpressionTree methodSelect = node.getMethodSelect();
if (!methodSelect.toString().equals("super")) {
assertTrue(methodSelect.toString(), !shouldMatch ^ toMatch.matches(node, visitorState));
}
return super.visitMethodInvocation(node, visitorState);
}
};
}
}