https://github.com/haskellari/time-compat/pull/33

From 9f7aa0a5937b800402359c3e82f4bee296ae8e06 Mon Sep 17 00:00:00 2001
From: matoro <matoro@users.noreply.github.com>
Date: Fri, 16 Sep 2022 11:19:20 -0400
Subject: [PATCH] Backport 6516a35 "fix resolution test" from time

The upstream version of time was incorrect in newer versions until
https://github.com/haskell/time/commit/6516a35b3d8cad14a21a559a5d2fc22ddda32fcc.
Because the compat implementation was correct and the upstream version
of time is now logically identical, simply replace both versions with
the current upstream time implementation.

See https://github.com/haskellari/time-compat/issues/31 for details on
which platforms the distinction matters.  Does NOT close that issue
though, because the original issue is for platforms on which the actual
resolution is less precise than the expected, and this will only fix
platforms on which the actual resolution is more precise.
---
 test/main/Test/Clock/Resolution.hs | 9 +++------
 1 file changed, 3 insertions(+), 6 deletions(-)

diff --git a/test/main/Test/Clock/Resolution.hs b/test/main/Test/Clock/Resolution.hs
index aab756b..4c0b1dd 100644
--- a/test/main/Test/Clock/Resolution.hs
+++ b/test/main/Test/Clock/Resolution.hs
@@ -25,7 +25,7 @@ gcdAll :: Real a => [a] -> a
 gcdAll = foldr gcd' 0
 
 testResolution :: (Show dt, Real dt) => String -> (at -> at -> dt) -> (dt, IO at) -> TestTree
-testResolution name timeDiff (res, getTime) =
+testResolution name timeDiff (reportedRes, getTime) =
     testCase name $ do
         t0 <- getTime
         times0 <-
@@ -53,11 +53,8 @@ testResolution name timeDiff (res, getTime) =
                 threadDelay 1000 -- 1ms
                 getTime
         let times = fmap (\t -> timeDiff t t0) $ times0 ++ times1 ++ times2 ++ times3 ++ times4
-#if MIN_VERSION_time(1,8,0)
-        assertEqual "resolution" res $ gcdAll times
-#else
-        assertBool ("resolution " ++ show (res, gcdAll times)) (res >= gcdAll times)
-#endif
+            foundGrid = gcdAll times
+        assertBool ("resolution " ++ show (reportedRes, foundGrid)) (foundGrid <= reportedRes)
 
 testResolutions :: TestTree
 testResolutions =