Action registry: run delayed actions in FIFO order instead of LIFO

Say we have two delayed actions we want to register in the following order:
close a file handle, and remove the corresponding file. When the action registry
is committed, then previously we would run the actions in LIFO order. This leads
to an error because we can't remove a file while we also have an open handle to
that file. Now that we run the actions in FIFO order, it works correctly.

Author: jorisdral

src-control/Control/ActionRegistry.hs

@@ -142,9 +142,12 @@ modifyWithActionRegistry_ getSt putSt action =
   can register delayed (commit) and rollback actions. The delayed actions are
   all executed at the end if the transaction scope is exited successfully, but
   if an exception is thrown (sync or async) then the rollback actions are
-  executed instead, and the exception is propagated. Delay or rollback actions
-  are executed in the reverse order in which they were registered, which is the
-  natural nesting order when considered as bracketing.
+  executed instead, and the exception is propagated.
+
+  * Rollback actions are executed in the reverse order in which they were
+  registered, which is the natural nesting order when considered as bracketing.
+
+  * Delayed actions are executed in the same order in which they are registered.
 -}
 
 -- | Registry of monadic actions supporting rollback actions and delayed actions
@@ -247,8 +250,8 @@ unsafeFinaliseActionRegistry reg ec = case ec of
 unsafeCommitActionRegistry :: (PrimMonad m, MonadCatch m) => ActionRegistry m -> m ()
 unsafeCommitActionRegistry reg = do
     as <- readMutVar (registryDelay reg)
-    -- Run actions in LIFO order
-    r <- runActions as
+    -- Run actions in FIFO order
+    r <- runActions (reverse as)
     case NE.nonEmpty r of
       Nothing         -> pure ()
       Just exceptions -> throwIO (CommitActionRegistryError exceptions)