[ViewVC] Diff of: jsr166/jsr166/src/test/tck/CompletableFutureTest.java

Comparing jsr166/src/test/tck/CompletableFutureTest.java (file contents):
Revision 1.122 by jsr166, Sun Sep 6 22:21:07 2015 UTC vs.
Revision 1.130 by jsr166, Sun Nov 15 17:21:44 2015 UTC

+import static java.util.concurrent.TimeUnit.MILLISECONDS;
+import static java.util.concurrent.TimeUnit.SECONDS;
-+
+import static java.util.concurrent.CompletableFuture.completedFuture;
-+
+import static java.util.concurrent.CompletableFuture.failedFuture;
-+
-+
+import java.lang.reflect.Method;
-+
+import java.lang.reflect.Modifier;
-+
-+
+import java.util.stream.Collectors;
-+
+import java.util.stream.Stream;
+import java.util.ArrayList;
-+
+import java.util.Arrays;
+import java.util.List;
+import java.util.Objects;
-+
+import java.util.Set;
+import java.util.concurrent.Callable;
+import java.util.concurrent.CancellationException;
+import java.util.concurrent.CompletableFuture;
+import java.util.function.BiFunction;
+import java.util.function.Consumer;
+import java.util.function.Function;
-+
+import java.util.function.Predicate;
+import java.util.function.Supplier;
-+
+import junit.framework.AssertionFailedError;
+import junit.framework.Test;
+import junit.framework.TestSuite;
+        if (!createIncomplete) assertTrue(f.complete(v1));
+        final CompletableFuture<Integer> g = f.exceptionally
+            ((Throwable t) -> {
-–
+                // Should not be called
+                a.getAndIncrement();
-<
+                throw new AssertionError();
->
+                threadFail("should not be called");
->
+                return null;            // unreached
+            });
+        if (createIncomplete) assertTrue(f.complete(v1));
+     * whenComplete action executes on normal completion, propagating
+     * source result.
+     */
-<
+    public void testWhenComplete_normalCompletion1() {
->
+    public void testWhenComplete_normalCompletion() {
+        for (ExecutionMode m : ExecutionMode.values())
+        for (boolean createIncomplete : new boolean[] { true, false })
+        for (Integer v1 : new Integer[] { 1, null })
+    }}
-+
+    /**
-+
+     * Minimal completion stages throw UOE for all non-CompletionStage methods
-+
+     */
-+
+    public void testMinimalCompletionStage_minimality() {
-+
+        if (!testImplementationDetails) return;
-+
+        Function<Method, String> toSignature =
-+
+            (method) -> method.getName() + Arrays.toString(method.getParameterTypes());
-+
+        Predicate<Method> isNotStatic =
-+
+            (method) -> (method.getModifiers() & Modifier.STATIC) == 0;
-+
+        List<Method> minimalMethods =
-+
+            Stream.of(Object.class, CompletionStage.class)
-+
+            .flatMap((klazz) -> Stream.of(klazz.getMethods()))
-+
+            .filter(isNotStatic)
-+
+            .collect(Collectors.toList());
-+
+        // Methods from CompletableFuture permitted NOT to throw UOE
-+
+        String[] signatureWhitelist = {
-+
+            "newIncompleteFuture[]",
-+
+            "defaultExecutor[]",
-+
+            "minimalCompletionStage[]",
-+
+            "copy[]",
-+
+        };
-+
+        Set<String> permittedMethodSignatures =
-+
+            Stream.concat(minimalMethods.stream().map(toSignature),
-+
+                          Stream.of(signatureWhitelist))
-+
+            .collect(Collectors.toSet());
-+
+        List<Method> allMethods = Stream.of(CompletableFuture.class.getMethods())
-+
+            .filter(isNotStatic)
-+
+            .filter((method) -> !permittedMethodSignatures.contains(toSignature.apply(method)))
-+
+            .collect(Collectors.toList());
-+
-+
+        CompletionStage<Integer> minimalStage =
-+
+            new CompletableFuture<Integer>().minimalCompletionStage();
-+
-+
+        List<Method> bugs = new ArrayList<>();
-+
+        for (Method method : allMethods) {
-+
+            Class<?>[] parameterTypes = method.getParameterTypes();
-+
+            Object[] args = new Object[parameterTypes.length];
-+
+            // Manufacture boxed primitives for primitive params
-+
+            for (int i = 0; i < args.length; i++) {
-+
+                Class<?> type = parameterTypes[i];
-+
+                if (parameterTypes[i] == boolean.class)
-+
+                    args[i] = false;
-+
+                else if (parameterTypes[i] == int.class)
-+
+                    args[i] = 0;
-+
+                else if (parameterTypes[i] == long.class)
-+
+                    args[i] = 0L;
-+
+            }
-+
+            try {
-+
+                method.invoke(minimalStage, args);
-+
+                bugs.add(method);
-+
+            }
-+
+            catch (java.lang.reflect.InvocationTargetException expected) {
-+
+                if (! (expected.getCause() instanceof UnsupportedOperationException)) {
-+
+                    bugs.add(method);
-+
+                    // expected.getCause().printStackTrace();
-+
+                }
-+
+            }
-+
+            catch (ReflectiveOperationException bad) { throw new Error(bad); }
-+
+        }
-+
+        if (!bugs.isEmpty())
-+
+            throw new Error("Methods did not throw UOE: " + bugs.toString());
-+
+    }
-+
-+
+    static class Monad {
-+
+        static class MonadError extends Error {
-+
+            public MonadError() { super("monadic zero"); }
-+
+        }
-+
+        // "return", "unit"
-+
+        static <T> CompletableFuture<T> unit(T value) {
-+
+            return completedFuture(value);
-+
+        }
-+
+        // monadic zero ?
-+
+        static <T> CompletableFuture<T> zero() {
-+
+            return failedFuture(new MonadError());
-+
+        }
-+
+        // >=>
-+
+        static <T,U,V> Function<T, CompletableFuture<V>> compose
-+
+            (Function<T, CompletableFuture<U>> f,
-+
+             Function<U, CompletableFuture<V>> g) {
-+
+            return (x) -> f.apply(x).thenCompose(g);
-+
+        }
-+
-+
+        static void assertZero(CompletableFuture<?> f) {
-+
+            try {
-+
+                f.getNow(null);
-+
+                throw new AssertionFailedError("should throw");
-+
+            } catch (CompletionException success) {
-+
+                assertTrue(success.getCause() instanceof MonadError);
-+
+            }
-+
+        }
-+
-+
+        static <T> void assertFutureEquals(CompletableFuture<T> f,
-+
+                                           CompletableFuture<T> g) {
-+
+            T fval = null, gval = null;
-+
+            Throwable fex = null, gex = null;
-+
-+
+            try { fval = f.get(); }
-+
+            catch (ExecutionException ex) { fex = ex.getCause(); }
-+
+            catch (Throwable ex) { fex = ex; }
-+
-+
+            try { gval = g.get(); }
-+
+            catch (ExecutionException ex) { gex = ex.getCause(); }
-+
+            catch (Throwable ex) { gex = ex; }
-+
-+
+            if (fex != null || gex != null)
-+
+                assertSame(fex.getClass(), gex.getClass());
-+
+            else
-+
+                assertEquals(fval, gval);
-+
+        }
-+
-+
+        static class PlusFuture<T> extends CompletableFuture<T> {
-+
+            AtomicReference<Throwable> firstFailure = new AtomicReference<>(null);
-+
+        }
-+
-+
+        // Monadic "plus"
-+
+        static <T> CompletableFuture<T> plus(CompletableFuture<? extends T> f,
-+
+                                             CompletableFuture<? extends T> g) {
-+
+            PlusFuture<T> plus = new PlusFuture<T>();
-+
+            BiConsumer<T, Throwable> action = (T result, Throwable ex) -> {
-+
+                if (ex == null) {
-+
+                    if (plus.complete(result))
-+
+                        if (plus.firstFailure.get() != null)
-+
+                            plus.firstFailure.set(null);
-+
+                }
-+
+                else if (plus.firstFailure.compareAndSet(null, ex)) {
-+
+                    if (plus.isDone())
-+
+                        plus.firstFailure.set(null);
-+
+                } else {
-+
+                    // prefer failing with first failure
-+
+                    plus.completeExceptionally(plus.firstFailure.getAndSet(null));
-+
+                }
-+
+            };
-+
+            f.whenComplete(action);
-+
+            g.whenComplete(action);
-+
+            return plus;
-+
+        }
-+
+    }
-+
-+
+    /**
-+
+     * CompletableFuture is an additive monad - sort of.
-+
+     * https://en.wikipedia.org/wiki/Monad_(functional_programming)#Additive_monads
-+
+     */
-+
+    public void testAdditiveMonad() throws Throwable {
-+
+        Function<Long, CompletableFuture<Long>> unit = Monad::unit;
-+
+        CompletableFuture<Long> zero = Monad.zero();
-+
-+
+        // Some mutually non-commutative functions
-+
+        Function<Long, CompletableFuture<Long>> triple
-+
+            = (x) -> Monad.unit(3 * x);
-+
+        Function<Long, CompletableFuture<Long>> inc
-+
+            = (x) -> Monad.unit(x + 1);
-+
-+
+        // unit is a right identity: m >>= unit === m
-+
+        Monad.assertFutureEquals(inc.apply(5L).thenCompose(unit),
-+
+                                 inc.apply(5L));
-+
+        // unit is a left identity: (unit x) >>= f === f x
-+
+        Monad.assertFutureEquals(unit.apply(5L).thenCompose(inc),
-+
+                                 inc.apply(5L));
-+
-+
+        // associativity: (m >>= f) >>= g === m >>= ( \x -> (f x >>= g) )
-+
+        Monad.assertFutureEquals(
-+
+            unit.apply(5L).thenCompose(inc).thenCompose(triple),
-+
+            unit.apply(5L).thenCompose((x) -> inc.apply(x).thenCompose(triple)));
-+
-+
+        // The case for CompletableFuture as an additive monad is weaker...
-+
-+
+        // zero is a monadic zero
-+
+        Monad.assertZero(zero);
-+
-+
+        // left zero: zero >>= f === zero
-+
+        Monad.assertZero(zero.thenCompose(inc));
-+
+        // right zero: f >>= (\x -> zero) === zero
-+
+        Monad.assertZero(inc.apply(5L).thenCompose((x) -> zero));
-+
-+
+        // f plus zero === f
-+
+        Monad.assertFutureEquals(Monad.unit(5L),
-+
+                                 Monad.plus(Monad.unit(5L), zero));
-+
+        // zero plus f === f
-+
+        Monad.assertFutureEquals(Monad.unit(5L),
-+
+                                 Monad.plus(zero, Monad.unit(5L)));
-+
+        // zero plus zero === zero
-+
+        Monad.assertZero(Monad.plus(zero, zero));
-+
+        {
-+
+            CompletableFuture<Long> f = Monad.plus(Monad.unit(5L),
-+
+                                                   Monad.unit(8L));
-+
+            // non-determinism
-+
+            assertTrue(f.get() == 5L || f.get() == 8L);
-+
+        }
-+
-+
+        CompletableFuture<Long> godot = new CompletableFuture<>();
-+
+        // f plus godot === f (doesn't wait for godot)
-+
+        Monad.assertFutureEquals(Monad.unit(5L),
-+
+                                 Monad.plus(Monad.unit(5L), godot));
-+
+        // godot plus f === f (doesn't wait for godot)
-+
+        Monad.assertFutureEquals(Monad.unit(5L),
-+
+                                 Monad.plus(godot, Monad.unit(5L)));
-+
+    }
-+
-+
+//     static <U> U join(CompletionStage<U> stage) {
-+
+//         CompletableFuture<U> f = new CompletableFuture<>();
-+
+//         stage.whenComplete((v, ex) -> {
-+
+//             if (ex != null) f.completeExceptionally(ex); else f.complete(v);
-+
+//         });
-+
+//         return f.join();
-+
+//     }
-+
-+
+//     static <U> boolean isDone(CompletionStage<U> stage) {
-+
+//         CompletableFuture<U> f = new CompletableFuture<>();
-+
+//         stage.whenComplete((v, ex) -> {
-+
+//             if (ex != null) f.completeExceptionally(ex); else f.complete(v);
-+
+//         });
-+
+//         return f.isDone();
-+
+//     }
-+
-+
+//     static <U> U join2(CompletionStage<U> stage) {
-+
+//         return stage.toCompletableFuture().copy().join();
-+
+//     }
-+
-+
+//     static <U> boolean isDone2(CompletionStage<U> stage) {
-+
+//         return stage.toCompletableFuture().copy().isDone();
-+
+//     }
-+

Diff Legend

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+Removed lines
-+
+Added lines
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+Changed lines
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+Changed lines

Comparing jsr166/src/test/tck/CompletableFutureTest.java (file contents): Revision 1.122 by jsr166, Sun Sep 6 22:21:07 2015 UTC vs. Revision 1.130 by jsr166, Sun Nov 15 17:21:44 2015 UTC

Diff Legend

Comparing jsr166/src/test/tck/CompletableFutureTest.java (file contents):
Revision 1.122 by jsr166, Sun Sep 6 22:21:07 2015 UTC vs.
Revision 1.130 by jsr166, Sun Nov 15 17:21:44 2015 UTC