From f0ba8d8d7711ff8ef60f4f3e529c18a435d5e92d Mon Sep 17 00:00:00 2001
From: Mrmaxmeier <Mrmaxmeier@gmail.com>
Date: Wed, 3 Dec 2025 16:45:39 +0100
Subject: [PATCH] haskellPackages.threads: add workaround for flaky test

---
 .../haskell-modules/configuration-nix.nix           |  3 +++
 .../patches/threads-flaky-test.patch                | 13 +++++++++++++
 2 files changed, 16 insertions(+)
 create mode 100644 pkgs/development/haskell-modules/patches/threads-flaky-test.patch

diff --git a/pkgs/development/haskell-modules/configuration-nix.nix b/pkgs/development/haskell-modules/configuration-nix.nix
index 24d363c906f0..2921711e97c9 100644
--- a/pkgs/development/haskell-modules/configuration-nix.nix
+++ b/pkgs/development/haskell-modules/configuration-nix.nix
@@ -2129,4 +2129,7 @@ builtins.intersectAttrs super {
   cpython = doJailbreak super.cpython;
 
   botan-bindings = super.botan-bindings.override { botan = pkgs.botan3; };
+
+  # Workaround for flaky test: https://github.com/basvandijk/threads/issues/10
+  threads = appendPatch ./patches/threads-flaky-test.patch super.threads;
 }
diff --git a/pkgs/development/haskell-modules/patches/threads-flaky-test.patch b/pkgs/development/haskell-modules/patches/threads-flaky-test.patch
new file mode 100644
index 000000000000..afbdf0dc4c76
--- /dev/null
+++ b/pkgs/development/haskell-modules/patches/threads-flaky-test.patch
@@ -0,0 +1,13 @@
+diff --git a/test/test.hs b/test/test.hs
+index 0251552..dc799a7 100644
+--- a/test/test.hs
++++ b/test/test.hs
+@@ -214,7 +214,7 @@ wrap :: (ThreadGroup -> Fork a) -> (Fork a -> IO b) -> IO b
+ wrap doFork test = ThreadGroup.new >>= test . doFork
+ 
+ test_group_single_wait :: (ThreadGroup -> Fork ()) -> Assertion
+-test_group_single_wait doFork = assert $ fmap isJustTrue $ timeout (10 * a_moment) $ do
++test_group_single_wait doFork = assert $ fmap isJustTrue $ timeout (100 * a_moment) $ do
+   tg <- ThreadGroup.new
+   r <- newIORef False
+   _ <- doFork tg $ do