Add support for GHC 9.10

Fixes #79

.github/workflows/ci.yml

@@ -69,11 +69,11 @@ jobs:
           - os: windows-latest
             ghc: 8.8.4
 
-        # # Uncomment if testing with an unreleased GHC. Make sure to edit the
-        # #  "Setup Haskell (head)" step too.
-        # include:
-        #   - os: ubuntu-22.04
-        #     ghc: head
+        # Uncomment if testing with an unreleased GHC. Make sure to edit the
+        #  "Setup Haskell (head)" step too.
+        include:
+          - os: ubuntu-22.04
+            ghc: head
       fail-fast: false
     steps:
       - name: Checkout
@@ -93,8 +93,9 @@ jobs:
           sudo apt-get update
           sudo apt-get install -y build-essential curl libffi-dev libffi8ubuntu1 libgmp-dev libgmp10 libncurses-dev libncurses5 libtinfo5
           curl --proto '=https' --tlsv1.2 -sSf https://get-ghcup.haskell.org | sh
-          ghcup install -u https://downloads.haskell.org/ghc/9.6.1/ghc-9.6.1-x86_64-deb9-linux.tar.xz ghc-head
-          ghcup set ghc ghc-head
+          ghcup config add-release-channel https://raw.githubusercontent.com/haskell/ghcup-metadata/master/ghcup-prereleases-0.0.8.yaml
+          ghcup install ghc 9.10.0.20240328
+          ghcup set ghc 9.10.0.20240328
           echo "cabal-store=$HOME/.cabal/store" >> $GITHUB_OUTPUT
 
       - name: Setup CI

cabal.project

@@ -3,7 +3,10 @@ packages:
 
 write-ghc-environment-files: always
 
+source-repository-package
+  type: git
+  location: https://github.com/haskell-unordered-containers/unordered-containers.git
+  tag: d52a0fd10bfa701cbbc9d7ac06bd7eb7664b3972
 
 allow-newer:
-    *:base
-  , *:ghc-bignum
+  unordered-containers:template-haskell

doctest-parallel.cabal

@@ -26,6 +26,7 @@ tested-with:
   , GHC == 9.4.7
   , GHC == 9.6.3
   , GHC == 9.8.1
+  , GHC == 9.10.1
 
 extra-source-files:
     example/example.cabal
@@ -102,7 +103,7 @@ library
     , directory
     , exceptions
     , filepath
-    , ghc >=8.2 && <9.9
+    , ghc >=8.2 && <9.11
     , ghc-paths >=0.1.0.9
     , process
     , random >= 1.2

src/Test/DocTest/Internal/Extract.hs

@@ -329,8 +329,10 @@ extractLit loc = \case
 #else
 #if __GLASGOW_HASKELL__ < 904
   HsPar _ (L l e) -> extractLit (locA l) e
-#else
+#elif __GLASGOW_HASKELL__ < 909
   HsPar _ _ (L l e) _ -> extractLit (locA l) e
+#else
+  HsPar _ (L l e) -> extractLit (locA l) e
 #endif
 #if __GLASGOW_HASKELL__ < 807
   ExprWithTySig _ (L l e) -> extractLit l e

src/Test/DocTest/Internal/Interpreter.hs

@@ -18,6 +18,9 @@ import System.Directory (getPermissions, executable)
 import Control.Monad
 import Control.Exception hiding (handle)
 import Data.Char
+#if __GLASGOW_HASKELL__ > 906
+import Data.List (unsnoc)
+#endif
 import GHC.Paths (ghc)
 
 import Test.DocTest.Internal.GhciWrapper
@@ -27,6 +30,19 @@ import Test.DocTest.Internal.Logging (DebugLogger)
 -- >>> import Test.DocTest.Internal.GhciWrapper (eval)
 -- >>> import Test.DocTest.Internal.Logging (noLogger)
 
+#if __GLASGOW_HASKELL__ <= 906
+-- | If the list is empty returns 'Nothing', otherwise returns the 'init' and the 'last'.
+--
+-- > unsnoc "test" == Just ("tes",'t')
+-- > unsnoc ""     == Nothing
+-- > \xs -> unsnoc xs == if null xs then Nothing else Just (init xs, last xs)
+unsnoc :: [a] -> Maybe ([a], a)
+unsnoc [] = Nothing
+unsnoc [x] = Just ([], x)
+unsnoc (x:xs) = Just (x:a, b)
+    where Just (a,b) = unsnoc xs
+#endif
+
 haveInterpreterKey :: String
 haveInterpreterKey = "Have interpreter"
 
@@ -76,13 +92,13 @@ safeEvalIt repl = either (return . Left) (fmap Right . evalIt repl) . filterExpr
 
 filterExpression :: String -> Either String String
 filterExpression e =
-  case lines e of
+  case map strip (lines e) of
     [] -> Right e
-    l  -> if firstLine == ":{" && lastLine /= ":}" then fail_ else Right e
-      where
-        firstLine = strip $ head l
-        lastLine  = strip $ last l
-        fail_ = Left "unterminated multiline command"
+    (firstLine:ls) ->
+      let lastLine = maybe firstLine snd (unsnoc ls) in
+      if firstLine == ":{" && lastLine /= ":}" then fail_ else Right e
   where
+    fail_ = Left "unterminated multiline command"
+
     strip :: String -> String
     strip = dropWhile isSpace . reverse . dropWhile isSpace . reverse

src/Test/DocTest/Internal/Runner/Example.hs

@@ -27,7 +27,7 @@ mkResult expected_ actual_ =
     -- use show to escape special characters in output lines if any output line
     -- contains any unsafe character
     escapeOutput
-      | any (not . isSafe) $ concat (expectedAsString ++ actual_) = init . tail . show . stripEnd
+      | any (not . isSafe) $ concat (expectedAsString ++ actual_) = init . drop 1 . show . stripEnd
       | otherwise = id
 
     actual :: [String]