com.google.errorprone.bugpatterns.ExpectedExceptionChecker.java Source code

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Here is the source code for com.google.errorprone.bugpatterns.ExpectedExceptionChecker.java

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/*
 * Copyright 2017 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.bugpatterns;

import static com.google.common.collect.ImmutableList.toImmutableList;
import static com.google.common.collect.Iterables.getLast;
import static com.google.errorprone.BugPattern.Category.JUNIT;
import static com.google.errorprone.BugPattern.SeverityLevel.WARNING;
import static com.google.errorprone.matchers.Description.NO_MATCH;

import com.google.common.collect.ImmutableList;
import com.google.common.collect.Lists;
import com.google.errorprone.BugPattern;
import com.google.errorprone.VisitorState;
import com.google.errorprone.fixes.Fix;
import com.google.errorprone.matchers.Description;
import com.google.errorprone.matchers.JUnitMatchers;
import com.sun.source.tree.MethodTree;
import com.sun.source.tree.StatementTree;
import com.sun.source.tree.Tree;
import java.util.List;

/** @author cushon@google.com (Liam Miller-Cushon) */
@BugPattern(name = "ExpectedExceptionChecker", category = JUNIT, summary = "Calls to ExpectedException#expect should always be followed by exactly one statement.", severity = WARNING)
public class ExpectedExceptionChecker extends AbstractExpectedExceptionChecker {

    @Override
    protected Description handleMatch(MethodTree tree, VisitorState state, List<Tree> expectations,
            List<StatementTree> suffix) {
        if (suffix.size() <= 1) {
            // for now, allow ExpectedException as long as it's testing that exactly one statement throws
            return NO_MATCH;
        }
        BaseFix baseFix = buildBaseFix(state, expectations);
        // provide fixes to wrap each of the trailing statements in a lambda
        // skip statements that look like assertions
        List<Fix> fixes = Lists.reverse(suffix).stream().filter(t -> !JUnitMatchers.containsTestMethod(t))
                .map(t -> baseFix.build(ImmutableList.of(t))).collect(toImmutableList());
        if (fixes.isEmpty()) {
            fixes.add(baseFix.build(ImmutableList.of(getLast(suffix))));
        }
        return buildDescription(tree).addAllFixes(fixes).build();
    }
}