From 2d2882cdfeb47c20bc6e1435abda268114e913b5 Mon Sep 17 00:00:00 2001
From: Gian Merlino <gianmerlino@gmail.com>
Date: Wed, 18 Sep 2024 16:08:47 -0700
Subject: [PATCH] Add test for exceptions in FutureUtils.transformAsync.
 (#17106)

Adds an additional test case to FutureUtilsTest.
---
 .../druid/common/guava/FutureUtilsTest.java   | 26 +++++++++++++++++++
 1 file changed, 26 insertions(+)

diff --git a/processing/src/test/java/org/apache/druid/common/guava/FutureUtilsTest.java b/processing/src/test/java/org/apache/druid/common/guava/FutureUtilsTest.java
index 52be34e78f9..9c261c7935f 100644
--- a/processing/src/test/java/org/apache/druid/common/guava/FutureUtilsTest.java
+++ b/processing/src/test/java/org/apache/druid/common/guava/FutureUtilsTest.java
@@ -243,6 +243,32 @@ public class FutureUtilsTest
     );
   }
 
+  @Test
+  public void test_transformAsync_exceptionInFunction()
+  {
+    final ListenableFuture<Object> f = FutureUtils.transformAsync(
+        Futures.immediateFuture("x"),
+        s -> {
+          throw new ISE("error!");
+        }
+    );
+
+    final ExecutionException e = Assert.assertThrows(
+        ExecutionException.class,
+        f::get
+    );
+
+    MatcherAssert.assertThat(
+        e,
+        ThrowableCauseMatcher.hasCause(CoreMatchers.instanceOf(ISE.class))
+    );
+
+    MatcherAssert.assertThat(
+        e,
+        ThrowableCauseMatcher.hasCause(ThrowableMessageMatcher.hasMessage(CoreMatchers.containsString("error!")))
+    );
+  }
+
   @Test
   public void test_coalesce_allOk() throws Exception
   {