Unwrap the ExecutionException in TimeLimiter and rethrow the cause at decorateFutureSupplier function (ReactiveX#529)

Author: MrRee1995

resilience4j-timelimiter/src/main/java/io/github/resilience4j/timelimiter/TimeLimiter.java

@@ -3,10 +3,7 @@
 import io.github.resilience4j.timelimiter.internal.TimeLimiterImpl;
 
 import java.time.Duration;
-import java.util.concurrent.Callable;
-import java.util.concurrent.Future;
-import java.util.concurrent.TimeUnit;
-import java.util.concurrent.TimeoutException;
+import java.util.concurrent.*;
 import java.util.function.Supplier;
 
 /**
@@ -66,6 +63,15 @@ static <T, F extends Future<T>> Callable<T> decorateFutureSupplier(TimeLimiter t
                     future.cancel(true);
                 }
                 throw e;
+            } catch (ExecutionException e){
+                Throwable t = e.getCause();
+                if (t == null){
+                    throw e;
+                }
+                if (t instanceof Error){
+                    throw (Error) t;
+                }
+                throw (Exception) t;
             }
         };
     }

resilience4j-timelimiter/src/test/java/io/github/resilience4j/timelimiter/TimeLimiterTest.java

@@ -79,4 +79,17 @@ public void shouldReturnResult() throws Exception {
         result = timeLimiter.decorateFutureSupplier(supplier).call();
         Assertions.assertThat(result).isEqualTo(42);
     }
+
+    @Test
+    public void unwrapExecutionException() {
+        TimeLimiter timeLimiter = TimeLimiter.ofDefaults();
+        ExecutorService executorService = Executors.newSingleThreadExecutor();
+
+        Supplier<Future<Integer>> supplier = () -> executorService.submit(() -> {throw new RuntimeException();});
+        Callable<Integer> decorated = TimeLimiter.decorateFutureSupplier(timeLimiter, supplier);
+
+        Try<Integer> decoratedResult = Try.ofCallable(decorated);
+
+        Assertions.assertThat(decoratedResult.getCause() instanceof RuntimeException).isTrue();
+    }
 }