From 6fde2272737713a58d888ae39628ad838f28c45f Mon Sep 17 00:00:00 2001
From: Jerry Lee <oldratlee@gmail.com>
Date: Sun, 2 Jun 2024 19:54:19 +0800
Subject: [PATCH] =?UTF-8?q?feat:=20report=20exception=20info=20of=20hop=20?=
 =?UTF-8?q?handle,=20errors=20should=20never=20pass=20silently=20?=
 =?UTF-8?q?=F0=9F=92=A3=20=F0=9F=91=80?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

---
 .../cffu/CompletableFutureUtils.java          | 21 ++++++++++++-------
 1 file changed, 14 insertions(+), 7 deletions(-)

diff --git a/cffu-core/src/main/java/io/foldright/cffu/CompletableFutureUtils.java b/cffu-core/src/main/java/io/foldright/cffu/CompletableFutureUtils.java
index ae22c2e6..15c23879 100644
--- a/cffu-core/src/main/java/io/foldright/cffu/CompletableFutureUtils.java
+++ b/cffu-core/src/main/java/io/foldright/cffu/CompletableFutureUtils.java
@@ -1271,7 +1271,7 @@ C peek(C cf, BiConsumer<? super T, ? super Throwable> action) {
         requireNonNull(cf, "cf is null");
         requireNonNull(action, "action is null");
 
-        cf.whenComplete(action).exceptionally(CompletableFutureUtils::reportExceptionInfoOfPeekAction);
+        cf.whenComplete(action).exceptionally(ex -> reportException("Exception occurred in the action of peek:", ex));
         return cf;
     }
 
@@ -1321,16 +1321,17 @@ C peekAsync(C cf, BiConsumer<? super T, ? super Throwable> action, Executor exec
         requireNonNull(action, "action is null");
         requireNonNull(executor, "executor is null");
 
-        cf.whenCompleteAsync(action, executor).exceptionally(CompletableFutureUtils::reportExceptionInfoOfPeekAction);
+        cf.whenCompleteAsync(action, executor).exceptionally(ex ->
+                reportException("Exception occurred in the action of peekAsync:", ex));
         return cf;
     }
 
     @Nullable
-    private static <T> T reportExceptionInfoOfPeekAction(Throwable ex) {
+    private static <T> T reportException(String msg, Throwable ex) {
         StringWriter sw = new StringWriter(4096);
         PrintWriter writer = new PrintWriter(sw);
 
-        writer.println("Exception occurred in the action of peek:");
+        writer.println(msg);
         ex.printStackTrace(writer);
 
         System.err.println(sw);
@@ -1642,14 +1643,20 @@ private static <C extends CompletableFuture<?>> C hopExecutorIfAtCfDelayerThread
             if (!atCfDelayerThread()) completeCf(ret, v, ex);
             else delayedExecutor(0, TimeUnit.SECONDS, asyncExecutor)
                     .execute(() -> completeCf(ret, v, ex));
-        });
+        }).exceptionally(ex -> reportException("Exception occurred in the input cf whenComplete of hop executor:", ex));
 
         return (C) ret;
     }
 
     private static void completeCf(CompletableFuture<Object> cf, Object value, @Nullable Throwable ex) {
-        if (ex == null) cf.complete(value);
-        else cf.completeExceptionally(ex);
+        try {
+            if (ex == null) cf.complete(value);
+            else cf.completeExceptionally(ex);
+        } catch (Throwable t) {
+            if (ex != null) t.addSuppressed(ex);
+            reportException("Exception occurred in completeCf:", t);
+            throw t; // rethrow exception, report to caller
+        }
     }
 
     //# Advanced methods of CompletionStage