From 39cfe2035d8af4ec1edecccb2974d778dedc79b8 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?L=C3=A9ana=20=E6=B1=9F?= <leana.jiang+git@icloud.com>
Date: Wed, 24 Sep 2025 11:01:52 +0000
Subject: [PATCH] test: freeze the callstack for better failure messages (#1)
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This would make the function `shouldLexTo` be transparent in the error reporting! Before all errors would point to this line.

Reviewed-on: https://git.elland.me/elland/haddock2/pulls/1
Co-authored-by: Léana 江 <leana.jiang+git@icloud.com>
Co-committed-by: Léana 江 <leana.jiang+git@icloud.com>
---
 test/Spec.hs | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/test/Spec.hs b/test/Spec.hs
index d202ac2..0a7653d 100644
--- a/test/Spec.hs
+++ b/test/Spec.hs
@@ -11,6 +11,7 @@ import Types
 import Data.String (IsString (..))
 import Data.Text (Text)
 import Text.Parsec.Pos
+import GHC.Stack
 
 main :: IO ()
 main = hspec $ do
@@ -185,6 +186,7 @@ instance IsString (Doc String) where
 
 shouldLexTo :: String -> [(Int, Int, Token)] -> Expectation
 shouldLexTo input expected =
+   withFrozenCallStack $
     case lexer input of
         Right tokens -> do
             let actual = map (\(pos, tok) -> (sourceLine pos, sourceColumn pos, tok)) tokens