Enable benchmarks by default when calculating plan (#432)

Author: hamishmack

lib/call-cabal-project-to-nix.nix

@@ -11,7 +11,11 @@
 , nix-tools     ? defaults.nix-tools
 , hpack         ? defaults.hpack
 , cabal-install ? defaults.cabal-install
-, configureArgs ? "" # Extra arguments to pass to `cabal new-configure` (--enable-tests is included by default, include `--disable-tests` to override that)
+, configureArgs ? "" # Extra arguments to pass to `cabal v2-configure`.
+                     # `--enable-tests --enable-benchmarks` are included by default.
+                     # If the tests and benchmarks are not needed and they
+                     # causes the wrong plan to be choosen, then we can use
+                     # `configureArgs = "--disable-tests --disable-benchmarks";`
 , ...
 }@args:
 # cabal-install versions before 2.4 will generate insufficient plan information.
@@ -201,10 +205,11 @@ let
       index-state =
         builtins.trace ("Using index-state: ${index-state-found}" + (if name == null then "" else " for " + name))
           index-state-found;
-      sha256 = index-sha256-found; }} cabal new-configure \
+      sha256 = index-sha256-found; }} cabal v2-configure \
         --with-ghc=${ghc.targetPrefix}ghc \
         --with-ghc-pkg=${ghc.targetPrefix}ghc-pkg \
         --enable-tests \
+        --enable-benchmarks \
         ${configureArgs}
 
     mkdir -p $out