builder: Add haddock and hoogle

builder/comp-builder.nix

@@ -16,6 +16,7 @@
 , preBuild ? null, postBuild ? null
 , preCheck ? null, postCheck ? null
 , preInstall ? null, postInstall ? null
+, preHaddock ? null, postHaddock ? null
 , shellHook ? null
 
 , doCheck ? component.doCheck || haskellLib.isTest componentId
@@ -25,6 +26,11 @@
 
 , static ? stdenv.hostPlatform.isMusl
 , deadCodeElimination ? true
+
+# Options for Haddock generation
+, doHaddock ? component.doHaddock  # Enable haddock and hoogle generation
+, doHoogle ? true  # Also build a hoogle index
+, hyperlinkSource ? true  # Link documentation to the source code
 }:
 
 let
@@ -164,7 +170,8 @@ let
       # other flags
       "--enable-executable-stripping"
       "--enable-library-stripping"
-    ] ++ lib.optional (deadCodeElimination && stdenv.hostPlatform.isLinux) "--enable-split-sections"
+    ] ++ lib.optional doHaddock' "--docdir=${docdir "$doc"}"
+      ++ lib.optional (deadCodeElimination && stdenv.hostPlatform.isLinux) "--enable-split-sections"
       ++ lib.optional (static) "--enable-static"
       ++ lib.optionals (stdenv.hostPlatform != stdenv.buildPlatform) (
         map (arg: "--hsc2hs-option=" + arg) ["--cross-compile" "--via-asm"]
@@ -182,7 +189,14 @@ let
     inherit package configFiles;
   };
 
-in stdenv.mkDerivation ({
+  # the target dir for haddock documentation
+  docdir = docoutput: docoutput + "/share/doc/" + componentId.cname;
+
+  doHaddock' = doHaddock && (haskellLib.isLibrary componentId);
+
+in stdenv.lib.fix (drv:
+
+stdenv.mkDerivation ({
   name = fullName;
 
   inherit src doCheck doCrossCheck dontPatchELF dontStrip;
@@ -192,6 +206,10 @@ in stdenv.mkDerivation ({
     config = component;
     inherit configFiles;
     env = shellWrappers;
+
+    # The directory containing the haddock documentation.
+    # `null' if no haddock documentation was built.
+    haddockDir = if doHaddock' then "${docdir drv.doc}/html" else null;
   };
 
   meta = {
@@ -216,13 +234,17 @@ in stdenv.mkDerivation ({
     ++ component.pkgconfig;
 
   nativeBuildInputs =
-    [ghc]
+    [ghc buildPackages.removeReferencesTo]
     ++ lib.optional (component.pkgconfig != []) pkgconfig
     ++ executableToolDepends;
 
   SETUP_HS = setup + /bin/Setup;
 
+  outputs = ["out" ] ++ (lib.optional doHaddock' "doc");
+
   # Phases
+  preInstallPhases = lib.optional doHaddock' "haddockPhase";
+
   prePatch = lib.optionalString (cabalFile != null) ''
     cat ${cabalFile} > ${package.identifier.name}.cabal
   '';
@@ -250,6 +272,32 @@ in stdenv.mkDerivation ({
     runHook postCheck
   '';
 
+  haddockPhase = ''
+    runHook preHaddock
+    docdir="${docdir "$doc"}"
+    mkdir -p "$docdir"
+
+    $SETUP_HS haddock \
+      "--html" \
+      ${lib.optionalString doHoogle "--hoogle"} \
+      ${lib.optionalString hyperlinkSource "--hyperlink-source"} \
+      ${lib.concatStringsSep " " component.setupHaddockFlags}
+
+    html="dist/doc/html/${componentId.cname}"
+
+    if [ -d "$html" ]; then
+       # Ensure that libraries are not pulled into the docs closure.
+       # As an example, the prettified source code of a
+       # Paths_package module will contain store paths of the library package.
+       for x in "$html/src/"*.html; do
+         remove-references-to -t $out $x
+       done
+
+       cp -R "$html" "$docdir"/html
+    fi
+    runHook postHaddock
+  '';
+
   # Note: Cabal does *not* copy test executables during the `install` phase.
   installPhase = ''
     runHook preInstall
@@ -278,15 +326,10 @@ in stdenv.mkDerivation ({
 }
 # patches can (if they like) depend on the version and revision of the package.
 // lib.optionalAttrs (patches != []) { patches = map (p: if builtins.isFunction p then p { inherit (package.identifier) version; inherit revision; } else p) patches; }
-// lib.optionalAttrs (preUnpack != "") { inherit preUnpack; }
-// lib.optionalAttrs (postUnpack != "") { inherit postUnpack; }
-// lib.optionalAttrs (preConfigure != "") { inherit preConfigure; }
-// lib.optionalAttrs (postConfigure != "") { inherit postConfigure; }
-// lib.optionalAttrs (preBuild != "") { inherit preBuild; }
-// lib.optionalAttrs (postBuild != "") { inherit postBuild; }
-// lib.optionalAttrs (preCheck != "") { inherit preCheck; }
-// lib.optionalAttrs (postCheck != "") { inherit postCheck; }
-// lib.optionalAttrs (preInstall != "") { inherit preInstall; }
-// lib.optionalAttrs (postInstall != "") { inherit postInstall; }
+// haskellLib.optionalHooks {
+  inherit preUnpack postUnpack preConfigure postConfigure
+    preBuild postBuild preCheck postCheck
+    preInstall postInstall preHaddock postHaddock;
+}
 // lib.optionalAttrs (stdenv.buildPlatform.libc == "glibc"){ LOCALE_ARCHIVE = "${buildPackages.glibcLocales}/lib/locale/locale-archive"; }
-)
+))

builder/default.nix

@@ -21,6 +21,8 @@
 , postCheck
 , preInstall
 , postInstall
+, preHaddock
+, postHaddock
 
 , shellHook
 
@@ -73,7 +75,9 @@ let
 
   buildComp = componentId: component: comp-builder {
     inherit componentId component package name src flags setup cabalFile patches revision
-            preUnpack postUnpack preConfigure postConfigure preBuild postBuild preCheck postCheck preInstall postInstall
+            preUnpack postUnpack preConfigure postConfigure
+            preBuild postBuild preCheck postCheck
+            preInstall postInstall preHaddock postHaddock
             shellHook
             ;
   };

lib/default.nix

@@ -61,6 +61,9 @@ with haskellLib;
     if componentId.ctype == "all" then ""
     else "${componentId.ctype}:${componentId.cname}";
 
+  # Remove null or empty values from an attrset.
+  optionalHooks = lib.filterAttrs (_: hook: hook != null && hook != "");
+
   # Avoid pkgs.callPackage for now. It does a lot of nonsense with OOP
   # style programming that we should avoid until we know we want it.
 

modules/package.nix

@@ -135,6 +135,10 @@ in {
             type = listOfFilteringNulls str;
             default = config.setupInstallFlags;
           };
+          setupHaddockFlags = mkOption {
+            type = listOfFilteringNulls str;
+            default = config.setupHaddockFlags;
+          };
           doExactConfig = mkOption {
             type = bool;
             default = config.doExactConfig;
@@ -147,6 +151,11 @@ in {
             type = bool;
             default = config.doCrossCheck;
           };
+          doHaddock = mkOption {
+            description = "Enable building of the Haddock documentation from the annotated Haskell source code.";
+            type = bool;
+            default = config.doHaddock;
+          };
         };
       };
     in {
@@ -225,6 +234,10 @@ in {
       type = listOfFilteringNulls str;
       default = [];
     };
+    setupHaddockFlags = mkOption {
+      type = listOfFilteringNulls str;
+      default = [];
+    };
     preUnpack = mkOption {
       type = nullOr lines;
       default = null;
@@ -265,6 +278,14 @@ in {
       type = nullOr string;
       default = null;
     };
+    preHaddock = mkOption {
+      type = nullOr string;
+      default = null;
+    };
+    postHaddock = mkOption {
+      type = nullOr string;
+      default = null;
+    };
     shellHook = mkOption {
       type = nullOr string;
       default = null;
@@ -282,6 +303,11 @@ in {
       type = bool;
       default = false;
     };
+    doHaddock = mkOption {
+      description = "Enable building of the Haddock documentation from the annotated Haskell source code.";
+      type = bool;
+      default = true;
+    };
   };
 
   # This has one quirk. Manually setting options on the all component

test/builder-haddock/Setup.hs

@@ -0,0 +1,2 @@
+import Distribution.Simple
+main = defaultMain

test/builder-haddock/TestHaddock.hs

@@ -0,0 +1,6 @@
+-- | Haddock test stuff
+module TestHaddock (hello) where
+
+-- | Standard hello text.
+hello :: String
+hello = "Hello, world!"

test/builder-haddock/default.nix

@@ -0,0 +1,92 @@
+{ pkgs
+, haskell
+, stdenv
+}:
+
+with stdenv.lib;
+
+let
+  pkgSet = haskell.mkPkgSet {
+    inherit pkgs;
+    # generated with:
+    #   cabal new-build
+    #   plan-to-nix dist-newstyle/cache/plan.json > plan.nix
+    #   cabal-to-nix test-haddock.cabal > test-haddock.nix
+    pkg-def = import ./plan.nix;
+    pkg-def-overlays = [
+      { test-haddock = ./test-haddock.nix; }
+    ];
+    modules = [
+      # overrides to fix the build
+      {
+        packages.transformers-compat.components.library.doExactConfig = true;
+      }
+
+      {
+        # Add a hook to the haddock phase
+        packages.test-haddock.postHaddock = ''
+          echo "==="
+          echo "This is the postHaddock hook. The files are:"
+          find .
+          echo "==="
+        '';
+
+        # Check that the package option works
+        packages.stm.doHaddock = false;
+      }
+    ];
+  };
+
+  packages = pkgSet.config.hsPkgs;
+
+in
+  stdenv.mkDerivation {
+    name = "builder-haddock-test";
+
+    buildCommand = let
+      inherit (packages.test-haddock.components) library;
+      noDocLibrary = packages.stm.components.library;
+    in ''
+      ########################################################################
+      # test haddock
+
+      doc="${toString library.doc}"
+      docDir="${toString library.haddockDir}"
+
+      # exeDoc="$ disabled {toString packages.test-haddock.components.exes.test-haddock.doc}"
+      # printf "checking that executable output does not have docs ... " >& 2
+      # echo $exeDoc
+      # test "$exeDoc" = ""
+
+      printf "checking that documentation directory was built... " >& 2
+      echo "$doc" >& 2
+      test -n "$doc"
+
+      printf "checking that documentation was generated... " >& 2
+      grep hello "$docDir/TestHaddock.html" > /dev/null
+      echo yes >& 2
+
+      printf "checking for hoogle index of package... " >& 2
+      grep hello "$docDir/test-haddock.txt" > /dev/null
+      echo yes >& 2
+
+      printf "checking for absence of documentation in another package... " >& 2
+      if [ -d "${toString noDocLibrary.haddockDir}" ]; then
+        echo "it exists - FAIL" >& 2
+      else
+        echo PASS >& 2
+      fi
+
+      printf "checking for absence of library package store paths in docs... " >& 2
+      if grep -R ${library} "$docDir" > /dev/null; then
+        echo "Found ${library} - FAIL" >& 2
+        exit 1
+      else
+        echo "PASS" >& 2
+      fi
+
+      touch $out
+    '';
+
+    meta.platforms = platforms.all;
+} // { inherit packages pkgSet; }

test/builder-haddock/plan.nix

@@ -0,0 +1,23 @@
+hackage:
+  {
+    packages = {
+      "ghc-prim".revision = hackage."ghc-prim"."0.5.2.0".revisions.default;
+      "stm".revision = hackage."stm"."2.4.5.1".revisions.default;
+      "rts".revision = hackage."rts"."1.0".revisions.default;
+      "base".revision = hackage."base"."4.11.1.0".revisions.default;
+      "array".revision = hackage."array"."0.5.2.0".revisions.default;
+      "integer-gmp".revision = hackage."integer-gmp"."1.0.2.0".revisions.default;
+    };
+    compiler = {
+      version = "8.4.4";
+      nix-name = "ghc844";
+      packages = {
+        "ghc-prim" = "0.5.2.0";
+        "stm" = "2.4.5.1";
+        "rts" = "1.0";
+        "base" = "4.11.1.0";
+        "array" = "0.5.2.0";
+        "integer-gmp" = "1.0.2.0";
+      };
+    };
+  }

test/builder-haddock/test-haddock.cabal

@@ -0,0 +1,15 @@
+cabal-version:       2.2
+name:                test-haddock
+version:             0.1.0.0
+license:             NONE
+author:              Rodney Lorrimar
+maintainer:          [email protected]
+
+library
+  exposed-modules:     TestHaddock
+  other-modules:       Paths_test_haddock
+  -- other-extensions:
+  build-depends:       base ^>=4.11.1.0
+                     , stm
+  -- hs-source-dirs:
+  default-language:    Haskell2010