add test/DynamicWind.java

test/DynamicWind.java

@@ -0,0 +1,305 @@
+import static avian.Continuations.callWithCurrentContinuation;
+import static avian.Continuations.dynamicWind;
+
+import avian.CallbackReceiver;
+import avian.Callback;
+
+import java.util.concurrent.Callable;
+
+public class DynamicWind {
+  private int before;
+  private int task;
+  private int after;
+  private int continuationCount;
+  private Callback<Integer> continuationReference;
+
+  private static void expect(boolean v) {
+    if (! v) throw new RuntimeException();
+  }
+
+  private void unwindTest(final Callable<Integer> unwind) throws Exception {
+    try {
+    expect(dynamicWind(new Runnable() {
+          public void run() {
+            System.out.println("unwindTest before");
+
+            expect(before == 0);
+            expect(task == 0);
+            expect(after == 0);
+
+            before = 1;
+          }
+        }, new Callable<Integer>() {
+            public Integer call() throws Exception {
+              System.out.println("unwindTest thunk");
+            
+              expect(before == 1);
+              expect(task == 0);
+              expect(after == 0);
+              
+              task = 1;
+
+              return unwind.call();
+            }
+          },
+          new Runnable() {
+            public void run() {
+              System.out.println("unwindTest after");
+            
+              expect(before == 1);
+              expect(task == 1);
+              expect(after == 0);
+
+              after = 1;
+            }
+          }) == 42);
+    } catch (MyException e) {
+      e.printStackTrace();
+    }
+
+    expect(before == 1);
+    expect(task == 1);
+    expect(after == 1);
+  }
+
+  private void normalUnwind() throws Exception {
+    unwindTest(new Callable<Integer>() {
+        public Integer call() {
+          return 42;
+        }
+      });
+  }
+
+  private void exceptionUnwind() throws Exception {
+    unwindTest(new Callable<Integer>() {
+        public Integer call() throws Exception {
+          throw new MyException();
+        }
+      });
+  }
+
+  private void continuationUnwindTest(final CallbackReceiver<Integer> receiver)
+    throws Exception
+  {
+    try {
+      expect(callWithCurrentContinuation(new CallbackReceiver<Integer>() {
+            public Integer receive(final Callback<Integer> continuation)
+              throws Exception
+            {
+              unwindTest(new Callable<Integer>() {
+                  public Integer call() throws Exception {
+                    return receiver.receive(continuation);
+                  }
+                });
+              throw new AssertionError();
+            }
+          }) == 42);
+    } catch (MyException e) {
+      e.printStackTrace();
+    }
+    
+    expect(before == 1);
+    expect(task == 1);
+    expect(after == 1);
+  }
+
+  private void continuationResultUnwind() throws Exception {
+    continuationUnwindTest(new CallbackReceiver<Integer>() {
+          public Integer receive(final Callback<Integer> continuation) {
+            continuation.handleResult(42);
+            throw new AssertionError();
+          }
+      });
+  }
+
+  private void continuationExceptionUnwind() throws Exception {
+    continuationUnwindTest(new CallbackReceiver<Integer>() {
+          public Integer receive(final Callback<Integer> continuation) {
+            continuation.handleException(new MyException());
+            throw new AssertionError();
+          }
+      });
+  }
+
+  private void rewindTest(final Callable<Integer> unwind, Runnable rewind)
+    throws Exception
+  {
+    int value;
+    try {
+      value = dynamicWind(new Runnable() {
+          public void run() {
+            expect(before == continuationCount);
+            expect(task == 0);
+            expect(after == 0);
+          
+            ++ before;
+          }
+        }, new Callable<Integer>() {
+          public Integer call() throws Exception {
+            expect(before == 1);
+            expect(task == 0);
+            expect(after == 0);
+          
+            task = 1;
+        
+            return callWithCurrentContinuation
+            (new CallbackReceiver<Integer>() {
+              public Integer receive(final Callback<Integer> continuation)
+                throws Exception
+              {
+                continuationReference = continuation;
+                return unwind.call();
+              }
+            });
+          }
+        }, new Runnable() {
+            public void run() {
+              expect(before == continuationCount + 1);
+              expect(task == 1);
+              expect(after == continuationCount);
+            
+              ++ after;
+            }
+          });
+    } catch (MyException e) {
+      value = e.value;
+    }
+
+    expect(value == continuationCount);
+    
+    if (value == 0) {
+      expect(before == 1);
+      expect(task == 1);
+      expect(after == 1);
+
+      continuationCount = 1;
+      rewind.run();
+      throw new AssertionError();
+    } else {
+      expect(value == 1);
+      expect(before == 2);
+      expect(task == 1);
+      expect(after == 2);
+    }
+  }
+
+  private void continuationResultRewind() throws Exception {
+    rewindTest(new Callable<Integer>() {
+        public Integer call() {
+          return 0;
+        }
+      }, new Runnable() {
+          public void run() {
+            continuationReference.handleResult(1);
+          }
+        });
+  }
+
+  private void continuationExceptionRewind() throws Exception {
+    rewindTest(new Callable<Integer>() {
+        public Integer call() throws Exception {
+          throw new MyException(0);
+        }
+      }, new Runnable() {
+          public void run() {
+            continuationReference.handleException(new MyException(1));
+          }
+        });
+  }
+
+  private void continuationResultUnwindAndRewind() throws Exception {
+    rewindTest(new Callable<Integer>() {
+        public Integer call() {
+          return 0;
+        }
+      }, new Runnable() {
+          public void run() {
+            try {
+              new DynamicWind().unwindTest(new Callable<Integer>() {
+                  public Integer call() {
+                    continuationReference.handleResult(1);
+                    throw new AssertionError();
+                  }
+              });
+            } catch (Exception e) {
+              throw new RuntimeException(e);
+            }
+          }
+        });
+  }
+
+  private void continuationExceptionUnwindAndRewind() throws Exception {
+    rewindTest(new Callable<Integer>() {
+        public Integer call() throws Exception {
+          throw new MyException(0);
+        }
+      }, new Runnable() {
+          public void run() {
+            try {
+              new DynamicWind().unwindTest(new Callable<Integer>() {
+                  public Integer call() {
+                    continuationReference.handleException(new MyException(1));
+                    throw new AssertionError();
+                  }
+              });
+            } catch (Exception e) {
+              throw new RuntimeException(e);
+            }
+          }
+        });
+  }
+
+  private void continuationResultUnwindAndRewindWithShared() throws Exception {
+    unwindTest(new Callable<Integer>() {
+        public Integer call() throws Exception {
+          new DynamicWind().continuationResultUnwindAndRewind();
+          return 42;
+        }
+      });
+  }
+
+  private void continuationExceptionUnwindAndRewindWithShared()
+    throws Exception
+  {
+    unwindTest(new Callable<Integer>() {
+        public Integer call() throws Exception {
+          new DynamicWind().continuationExceptionUnwindAndRewind();
+          return 42;
+        }
+      });
+  }
+
+  public static void main(String[] args) throws Exception {
+    new DynamicWind().normalUnwind();
+
+    new DynamicWind().exceptionUnwind();
+
+    new DynamicWind().continuationResultUnwind();
+
+    new DynamicWind().continuationExceptionUnwind();
+
+    new DynamicWind().continuationResultRewind();
+
+    new DynamicWind().continuationExceptionRewind();
+
+    new DynamicWind().continuationResultUnwindAndRewind();
+
+    new DynamicWind().continuationExceptionUnwindAndRewind();
+
+    new DynamicWind().continuationResultUnwindAndRewindWithShared();
+
+    new DynamicWind().continuationExceptionUnwindAndRewindWithShared();
+  }
+
+  private static class MyException extends Exception { 
+    public final int value;
+
+    public MyException() {
+      this(0);
+    }
+
+    public MyException(int value) {
+      this.value = value;
+    }
+  }
+}