wip

builder/comp-builder.nix

@@ -1,6 +1,7 @@
 { stdenv, buildPackages, ghc, lib, pkgconfig, gobject-introspection ? null, haskellLib, makeConfigFiles, ghcForComponent, hsPkgs, runCommand, libffi, gmp }:
 
-{ componentId
+{ allComponent
+, componentId
 , component
 , package
 , name
@@ -19,6 +20,7 @@
 , preInstall ? component.preInstall , postInstall ? component.postInstall
 , preHaddock ? component.preHaddock , postHaddock ? component.postHaddock
 , shellHook ? ""
+, isDoctest ? component.isDoctest
 
 , dontPatchELF ? component.dontPatchELF
 , dontStrip ? component.dontStrip
@@ -52,10 +54,19 @@ let
     then "${name}-all"
     else "${name}-${componentId.ctype}-${componentId.cname}";
 
-  configFiles = makeConfigFiles {
-    inherit (package) identifier;
-    inherit component fullName flags;
-  };
+  configFiles =
+    if isDoctest
+    then
+      makeConfigFiles {
+        inherit (package) identifier;
+        component = allComponent;
+        inherit fullName flags;
+      }
+    else
+      makeConfigFiles {
+        inherit (package) identifier;
+        inherit component fullName flags;
+      };
 
   enableFeature = enable: feature:
     (if enable then "--enable-" else "--disable-") + feature;
@@ -64,7 +75,7 @@ let
 
   finalConfigureFlags = lib.concatStringsSep " " (
     [ "--prefix=$out"
-      "${haskellLib.componentTarget componentId}"
+      "${haskellLib.componentSetupTarget componentId component}"
       "$(cat ${configFiles}/configure-flags)"
       # GHC
       "--with-ghc=${ghc.targetPrefix}ghc"
@@ -188,10 +199,11 @@ stdenv.mkDerivation ({
 
   SETUP_HS = setup + /bin/Setup;
 
-  outputs = ["out" ]
+  outputs = ["out"]
     ++ (lib.optional enableSeparateDataOutput "data")
     ++ (lib.optional doHaddock' "doc")
-    ++ (lib.optional keepSource "source");
+    ++ (lib.optional keepSource "source")
+    ++ (lib.optional isDoctest "dist");
 
   # Phases
   preInstallPhases = lib.optional doHaddock' "haddockPhase";
@@ -219,7 +231,7 @@ stdenv.mkDerivation ({
   buildPhase = ''
     runHook preBuild
     # https://gitlab.haskell.org/ghc/ghc/issues/9221
-    $SETUP_HS build ${haskellLib.componentTarget componentId} -j$(($NIX_BUILD_CORES > 4 ? 4 : $NIX_BUILD_CORES)) ${lib.concatStringsSep " " (component.setupBuildFlags ++ setupGhcOptions)}
+    $SETUP_HS build ${haskellLib.componentBuildTarget componentId component} -j$(($NIX_BUILD_CORES > 4 ? 4 : $NIX_BUILD_CORES)) ${lib.concatStringsSep " " (component.setupBuildFlags ++ setupGhcOptions)}
     runHook postBuild
   '';
 
@@ -325,7 +337,9 @@ stdenv.mkDerivation ({
     '')
     }
     runHook postInstall
-  '' + (lib.optionalString keepSource ''
+  '' + (lib.optionalString isDoctest ''
+    cp -r dist/ $dist/
+  '') + (lib.optionalString keepSource ''
     rm -rf dist
   '');
 

builder/hspkg-builder.nix

@@ -51,14 +51,14 @@ let
       inherit (config) preUnpack postUnpack;
     };
 
-  buildComp = componentId: component: comp-builder {
-    inherit componentId component package name src flags setup cabalFile cabal-generator patches revision
+  buildComp = allComponent: componentId: component: comp-builder {
+    inherit allComponent componentId component package name src flags setup cabalFile cabal-generator patches revision
             shellHook
             ;
   };
 
 in rec {
-  components = haskellLib.applyComponents buildComp config;
+  components = haskellLib.applyComponents (buildComp config.components.all) config;
   checks = pkgs.recurseIntoAttrs (builtins.mapAttrs
     (_: d: haskellLib.check d)
       (lib.filterAttrs (_: d: d.config.doCheck) components.tests));

lib/check.nix

@@ -10,7 +10,7 @@ let
 in stdenv.mkDerivation ({
   name = (drv.name + "-check");
 
-  # Useing `srcOnly` (rather than getting the `src` via a `drv.passthru`)
+  # Using `srcOnly` (rather than getting the `src` via a `drv.passthru`)
   # should correctly apply the patches from `drv` (if any).
   src = drv.source or (srcOnly drv);
 
@@ -26,15 +26,29 @@ in stdenv.mkDerivation ({
 
   # If doCheck or doCrossCheck are false we may still build this
   # component and we want it to quietly succeed.
-  buildPhase = ''
-    touch $out
-
-    runHook preCheck
-
-    ${toString component.testWrapper} ${drv}/bin/${drv.exeName} ${lib.concatStringsSep " " component.testFlags} | tee $out
-
-    runHook postCheck
-  '';
+  buildPhase =
+    (lib.optionalString component.isDoctest ''
+      # cabal-doctest assumes we are running tests in a directory with the same
+      # name as when we built the test.
+      this_dir_name=$(pwd)
+      src_basename="$(basename "${drv.cleanSrc}")"
+      cd ../
+      mv "$this_dir_name" "$src_basename"
+      cd "$src_basename"
+
+      # cabal-doctest needs the ./dist directory available to get auto-generated
+      # modules.
+      cp -r ${drv.dist} ./dist
+      chmod u+w -R ./dist
+    '') + ''
+      touch $out
+
+      runHook preCheck
+
+      ${toString component.testWrapper} ${drv}/bin/${drv.exeName} ${lib.concatStringsSep " " component.testFlags} | tee $out
+
+      runHook postCheck
+    '';
 } // haskellLib.optionalHooks {
   inherit (component) preCheck postCheck;
 }

lib/default.nix

@@ -81,8 +81,20 @@ with haskellLib;
 
   # Format a componentId as it should appear as a target on the
   # command line of the setup script.
-  componentTarget = componentId:
-    if componentId.ctype == "all" then ""
+  componentSetupTarget = componentId: component:
+    if componentId.ctype == "all"
+    then ""
+    else
+      if component.isDoctest
+      # TODO: Why is this needed???
+      then "--enable-tests"
+      else "${componentId.ctype}:${componentId.cname}";
+
+  # Format a componentId as it should appear as a target on the
+  # command line of the setup script.
+  componentBuildTarget = componentId: component:
+    if componentId.ctype == "all"
+    then ""
     else "${componentId.ctype}:${componentId.cname}";
 
   # Remove null or empty values from an attrset.

modules/plan.nix

@@ -128,6 +128,10 @@ let
             type = bool;
             default = (def.enableShared or true);
           };
+          isDoctest = mkOption {
+            type = bool;
+            default = false;
+          };
           shellHook = mkOption {
             description = "Hook to run when entering a shell";
             type = unspecified; # Can be either a string or a function