package com.atlassian.vcache.internal.core;
   
   import com.atlassian.vcache.internal.RequestContext;
   import org.junit.Rule;
   import org.junit.Test;
   import org.junit.rules.ExpectedException;
   
   import java.util.HashMap;
   import java.util.Map;
  
  import static org.hamcrest.Matchers.is;
  import static org.junit.Assert.assertThat;
  
  public class DefaultRequestContextTest {
      @Rule
      public ExpectedException thrown = ExpectedException.none();
  
      @Test
      public void partitionIdentifier() throws Exception {
          final RequestContext rc = new DefaultRequestContext(() -> "tenant");
  
          assertThat(rc.partitionIdentifier(), is("tenant"));
      }
  
      @Test
      public void computeIfAbsent_normal() throws Exception {
          final RequestContext rc = new DefaultRequestContext(() -> "ignored");
          final String missing = rc.computeIfAbsent("missing", () -> "generated");
  
          assertThat(missing, is("generated"));
  
          final String exists = rc.computeIfAbsent("missing", () -> "wtf");
  
          assertThat(exists, is("generated"));
      }
  
      @Test
      public void computeIfAbsent_cast_error() throws Exception {
          final RequestContext rc = new DefaultRequestContext(() -> "ignored");
          rc.computeIfAbsent("key", () -> "value");
  
          thrown.expect(ClassCastException.class);
  
          final Integer i = rc.computeIfAbsent("key", () -> 42);
      }
  
      @Test
      public void verifyComputeIfAbsent() {
          // If this test fails, it means that Oracle have fixed https://bugs.openjdk.java.net/browse/JDK-8071667.
          // If so, consider fixing the implementation of `com.atlassian.vcache.internal.RequestContext.computeIfAbsent`.
  
          final int LIMIT = 64;
          final Map<String, String> map = new HashMap<>();
          final String KEY = "key";
  
          map.computeIfAbsent(KEY, k -> {
              for (int i = 0; i < LIMIT; ++i) {
                  map.put(i + "", "junk");
              }
              return "value";
          });
  
          // Should actually by true.
          assertThat(map.containsKey(KEY), is(false));
      }
  }