From 2cd2341673144682569d9eb98915e12919bc4246 Mon Sep 17 00:00:00 2001
From: George Thomas <georgefsthomas@gmail.com>
Date: Tue, 30 Dec 2025 12:03:21 +0000
Subject: [PATCH] Share frame generation to avoid accidental quadratic
 complexity

Previously each test was computing all frames from scratch.
---
 haskell/Puzzles/Day4.hs | 10 +++++-----
 1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/haskell/Puzzles/Day4.hs b/haskell/Puzzles/Day4.hs
index 25f409b..ad758fe 100644
--- a/haskell/Puzzles/Day4.hs
+++ b/haskell/Puzzles/Day4.hs
@@ -26,11 +26,11 @@ puzzle =
                 t <- TL.readFile if isRealData then "../inputs/real/4" else "../inputs/examples/4"
                 input' <- input
                 t @=? drawGrid (mkGrid input' <&> \case InEmpty -> OutEmpty; InRoll -> OutRoll)
-            , testGroup
-                "frames"
-                let frames = Seq.fromList . takeUntil noneAccessible . fmap snd . generateFrames . mkGrid <$> input
-                    nFrames = if isRealData then 58 else 9
-                 in ( [0 .. nFrames] <&> \n ->
+            , withResource
+                (Seq.fromList . takeUntil noneAccessible . fmap snd . generateFrames . mkGrid <$> input)
+                mempty
+                \frames -> testGroup "frames" let nFrames = if isRealData then 58 else 9 in
+                    ( [0 .. nFrames] <&> \n ->
                         goldenVsStringDiff (show n) diffCommand (path <> "frames/" <> show n) $
                             TL.encodeUtf8 . maybe "frame list too short!" drawGrid . Seq.lookup n <$> frames
                     )