Support dhall on GHC 9.8 (#253)

.github/workflows/ci.yml

@@ -36,8 +36,6 @@ jobs:
             largeRecords: true
           - compiler: ghc982
             largeRecords: true
-          - compiler: ghc982
-            dhall: true
           - compiler: ghc902
             os: macos-latest
     runs-on: ${{ matrix.os }}

CHANGELOG.md

@@ -1,5 +1,6 @@
 # 0.8.1
 * Fix support for dhall-1.42.
+* Support dhall on GHC 9.8.
 * Fix aeson upper bound in library target (was correct in test target).
 * Fix default compiler version in shell.nix.
 * Test with GHC 9.8.2 instead of GHC 9.8.1 and GHC 9.6.5 instead of GHC 9.6.2.

README.md

@@ -23,8 +23,8 @@ for more details.
 
 #### GHC 9.8
 
-We do not support features making use of the "dhall" or "large-records"
-libraries because neither library currently builds on GHC 9.8, and
+We do not support features making use of the "large-records"
+library because it does not currently build on GHC 9.8, and
 therefore we cannot test our support.
 
 Otherwise we support GHC 9.8 on Linux and Darwin.

nix/overlays/haskell-packages.nix

@@ -118,6 +118,12 @@ in {
           half =
             pkgsNew.haskell.lib.doJailbreak haskellPackagesOld.half;
 
+          # With nixpkgs-24.05 and ghc982, we observed a non-reproducible
+          # failure of the hedgehog tests.  Rather than risk occasional
+          # failures building this test dependency, we skip its tests.
+          hedgehog =
+            pkgsNew.haskell.lib.dontCheck haskellPackagesOld.hedgehog;
+
           # With nixpkgs-23.11 and ghc981, hourglass does not support the version
           # of the time package that is provided, but that matters only to tests.
           hourglass =