Merge pull request #11929 from cabalism/fix/cabal-doctest-ghc-9.12

Running cabal doctest with ghc-9.12

Author: mergify[bot]

.github/workflows/quick-jobs.yml

@@ -15,7 +15,7 @@ on:
       - created
 
 env:
-  GHC_FOR_QUICK_JOBS: 9.10.3
+  GHC_FOR_QUICK_JOBS: 9.12.2
 
 jobs:
   meta:

Makefile

@@ -151,15 +151,21 @@ ghcid-cli: ## Run ghcid for the cabal-install executable.
 
 .PHONY: doctest
 doctest: ## Run doctests.
+	cabal --numeric-version
 	cd Cabal-syntax && $(DOCTEST)
 	cd Cabal-described && $(DOCTEST)
 	cd Cabal && $(DOCTEST)
 	cd cabal-install-solver && $(DOCTEST)
 	cd cabal-install && $(DOCTEST)
 
+# If we pin and periodically bump the version of doctest, we get more
+# reproducible testing. Initially we pinned to doctest-0.25.0 to avoid failures
+# with doctest-0.24.3 but `cabal install doctest` depends on index state that
+# itself gets bumped when `cabal update --ignore-project` is run.
+# SEE: https://github.com/haskell/cabal/issues/11493#issuecomment-4615438425
 .PHONY: doctest-install
 doctest-install: ## Install doctest tool needed for running doctests.
-	cabal install doctest --overwrite-policy=always --ignore-project --flag cabal-doctest
+	cabal install doctest-0.25.0 --overwrite-policy=always --ignore-project --flag cabal-doctest
 
 # tests