plugins/InspectionGadgets/InspectionGadgetsAnalysis/src/com/siyeh/ig/junit/TestMethodWithoutAssertionInspectionBase.java

/*
 * Copyright 2000-2014 JetBrains s.r.o.
 *
 * 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.siyeh.ig.junit;

import com.intellij.openapi.util.InvalidDataException;
import com.intellij.openapi.util.WriteExternalException;
import com.intellij.psi.*;
import com.intellij.psi.util.InheritanceUtil;
import com.siyeh.InspectionGadgetsBundle;
import com.siyeh.ig.BaseInspection;
import com.siyeh.ig.BaseInspectionVisitor;
import com.siyeh.ig.psiutils.TestUtils;
import org.jdom.Element;
import org.jetbrains.annotations.NonNls;
import org.jetbrains.annotations.NotNull;

import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import java.util.regex.Matcher;
import java.util.regex.Pattern;
import java.util.regex.PatternSyntaxException;

public class TestMethodWithoutAssertionInspectionBase extends BaseInspection {
  protected final List<String> methodNamePatterns = new ArrayList<String>();
  protected final List<String> classNames = new ArrayList<String>();
  /**
   * @noinspection PublicField
   */
  @NonNls public String assertionMethods =
    "org.junit.Assert,assert.*|fail.*," +
    "junit.framework.Assert,assert.*|fail.*," +
    "org.mockito.Mockito,verify.*," +
    "org.mockito.InOrder,verify," +
    "org.junit.rules.ExpectedException,expect.*," +
    "org.hamcrest.MatcherAssert,assertThat";
  @SuppressWarnings({"PublicField"})
  public boolean assertKeywordIsAssertion = false;
  private Map<String, Pattern> patternCache = null;

  public TestMethodWithoutAssertionInspectionBase() {
    parseString(assertionMethods, classNames, methodNamePatterns);
  }

  @Override
  @NotNull
  public String getID() {
    return "JUnitTestMethodWithNoAssertions";
  }

  @Override
  @NotNull
  public String getDisplayName() {
    return InspectionGadgetsBundle.message("test.method.without.assertion.display.name");
  }

  @Override
  @NotNull
  protected String buildErrorString(Object... infos) {
    return InspectionGadgetsBundle.message("test.method.without.assertion.problem.descriptor");
  }

  @Override
  public void readSettings(@NotNull Element element) throws InvalidDataException {
    super.readSettings(element);
    parseString(assertionMethods, classNames, methodNamePatterns);
  }

  @Override
  public void writeSettings(@NotNull Element element) throws WriteExternalException {
    assertionMethods = formatString(classNames, methodNamePatterns);
    super.writeSettings(element);
  }

  @Override
  public BaseInspectionVisitor buildVisitor() {
    return new TestMethodWithoutAssertionVisitor();
  }

  private boolean methodNamesMatch(String methodName, String methodNamePattern) {
    Pattern pattern;
    if (patternCache != null) {
      pattern = patternCache.get(methodNamePattern);
    }
    else {
      patternCache = new HashMap<String, Pattern>(methodNamePatterns.size());
      pattern = null;
    }
    if (pattern == null) {
      try {
        pattern = Pattern.compile(methodNamePattern);
        patternCache.put(methodNamePattern, pattern);
      }
      catch (PatternSyntaxException ignore) {
        return false;
      }
      catch (NullPointerException ignore) {
        return false;
      }
    }
    if (pattern == null) {
      return false;
    }
    final Matcher matcher = pattern.matcher(methodName);
    return matcher.matches();
  }

  private class TestMethodWithoutAssertionVisitor
    extends BaseInspectionVisitor {

    @Override
    public void visitMethod(@NotNull PsiMethod method) {
      super.visitMethod(method);
      if (!TestUtils.isJUnitTestMethod(method)) {
        return;
      }
      if (hasExpectedExceptionAnnotation(method)) {
        return;
      }
      if (containsAssertion(method)) {
        return;
      }
      if (lastStatementIsCallToMethodWithAssertion(method)) {
        return;
      }
      registerMethodError(method);
    }

    private boolean lastStatementIsCallToMethodWithAssertion(PsiMethod method) {
      final PsiCodeBlock body = method.getBody();
      if (body == null) {
        return false;
      }
      final PsiStatement[] statements = body.getStatements();
      if (statements.length <= 0) {
        return false;
      }
      final PsiStatement lastStatement = statements[0];
      if (!(lastStatement instanceof PsiExpressionStatement)) {
        return false;
      }
      final PsiExpressionStatement expressionStatement = (PsiExpressionStatement)lastStatement;
      final PsiExpression expression = expressionStatement.getExpression();
      if (!(expression instanceof PsiMethodCallExpression)) {
        return false;
      }
      final PsiMethodCallExpression methodCallExpression = (PsiMethodCallExpression)expression;
      final PsiReferenceExpression methodExpression = methodCallExpression.getMethodExpression();
      final PsiExpression qualifierExpression = methodExpression.getQualifierExpression();
      if (qualifierExpression != null && !(qualifierExpression instanceof PsiThisExpression)) {
        return false;
      }
      final PsiMethod targetMethod = methodCallExpression.resolveMethod();
      return containsAssertion(targetMethod);
    }

    private boolean containsAssertion(PsiElement element) {
      if (element == null) {
        return false;
      }
      final ContainsAssertionVisitor
        visitor = new ContainsAssertionVisitor();
      element.accept(visitor);
      return visitor.containsAssertion();
    }

    private boolean hasExpectedExceptionAnnotation(PsiMethod method) {
      final PsiModifierList modifierList = method.getModifierList();
      final PsiAnnotation testAnnotation = modifierList.findAnnotation("org.junit.Test");
      if (testAnnotation == null) {
        return false;
      }
      final PsiAnnotationParameterList parameterList = testAnnotation.getParameterList();
      final PsiNameValuePair[] nameValuePairs = parameterList.getAttributes();
      for (PsiNameValuePair nameValuePair : nameValuePairs) {
        @NonNls final String parameterName = nameValuePair.getName();
        if ("expected".equals(parameterName)) {
          return true;
        }
      }
      return false;
    }
  }

  private class ContainsAssertionVisitor extends JavaRecursiveElementVisitor {

    private boolean containsAssertion = false;

    @Override
    public void visitElement(@NotNull PsiElement element) {
      if (!containsAssertion) {
        super.visitElement(element);
      }
    }

    @Override
    public void visitMethodCallExpression(@NotNull PsiMethodCallExpression call) {
      if (containsAssertion) {
        return;
      }
      super.visitMethodCallExpression(call);
      final PsiReferenceExpression methodExpression = call.getMethodExpression();
      @NonNls final String methodName = methodExpression.getReferenceName();
      if (methodName == null) {
        return;
      }
      final int methodNamesSize = methodNamePatterns.size();
      for (int i = 0; i < methodNamesSize; i++) {
        final String pattern = methodNamePatterns.get(i);
        if (!methodNamesMatch(methodName, pattern)) {
          continue;
        }
        final PsiMethod method = call.resolveMethod();
        if (method == null || method.isConstructor()) {
          continue;
        }
        final PsiClass aClass = method.getContainingClass();
        if (!InheritanceUtil.isInheritor(aClass, classNames.get(i))) {
          continue;
        }
        containsAssertion = true;
        break;
      }
    }

    @Override
    public void visitAssertStatement(PsiAssertStatement statement) {
      if (containsAssertion) {
        return;
      }
      super.visitAssertStatement(statement);
      if (!assertKeywordIsAssertion) {
        return;
      }
      containsAssertion = true;
    }

    public boolean containsAssertion() {
      return containsAssertion;
    }
  }
}