code: /*
   * Licensed to the Apache Software Foundation (ASF) under one or more
   * contributor license agreements.  See the NOTICE file distributed with
   * this work for additional information regarding copyright ownership.
   * The ASF licenses this file to You 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 org.apache.skywalking.oap.server.core.alarm.provider.expression;
  
  import com.google.common.collect.Sets;
  import org.junit.jupiter.api.BeforeEach;
  import org.junit.jupiter.api.Test;
  import org.mvel2.CompileException;
  
  import java.util.HashMap;
  import java.util.Map;
  import java.util.Set;
  
  import static org.assertj.core.api.AssertionsForClassTypes.assertThat;
  import static org.junit.jupiter.api.Assertions.assertNotNull;
  import static org.junit.jupiter.api.Assertions.assertNull;
  import static org.junit.jupiter.api.Assertions.assertThrows;
  
  public class ExpressionTest {
      private Expression expression;
  
      @BeforeEach
      public void init() {
          expression = new Expression(new ExpressionContext());
      }
  
      @Test
      public void testEval() {
          String expr = " a && b ";
          Map<String, Object> dataMap = new HashMap();
          dataMap.put("a", Boolean.TRUE);
          Object flag = expression.eval(expr, dataMap);
          assertNull(flag);
          dataMap.put("b", Boolean.TRUE);
          flag = expression.eval(expr, dataMap);
          assertThat(flag).isEqualTo(true);
      }
  
      @Test
      public void testAnalysisInputs() {
          String expr = " a && b ";
          Set<String> inputs = expression.analysisInputs(expr);
          assertThat(inputs.size()).isEqualTo(2);
          assertThat(inputs).isEqualTo(Sets.newHashSet("a", "b"));
      }
  
      @Test
      public void testEvalWithEmptyContext() {
          String expr = " a && b ";
          Object flag = expression.eval(expr);
          assertNull(flag);
          flag = expression.eval(" 1 > 0");
          assertThat(flag).isEqualTo(true);
      }
  
      @Test
      public void testCompile() {
          String expr = " a && b ";
          ExpressionContext context = new ExpressionContext();
          Object compiledExpression = expression.compile(expr, context);
          assertNotNull(compiledExpression);
          Object sameExpression = expression.compile(expr, context);
          assertThat(compiledExpression).isEqualTo(sameExpression);
      }
  
      @Test
      public void testCompileWithException() {
          assertThrows(CompileException.class, () -> {
              String expr = " a && * b ";
              ExpressionContext context = new ExpressionContext();
              expression.compile(expr, context);
          });
      }
  }
  