From 91ab6c9e899605be047e0e96af1144b964e6b64e Mon Sep 17 00:00:00 2001
From: John Ericson <Ericson2314@Yahoo.com>
Date: Mon, 18 May 2015 04:50:37 +0000
Subject: [PATCH] agda: Wrapper is no longer built by default

Instead it is provided to the user who can choose whether or not
to include it in the final derivati. Example of including would
be:

```nix
callPackage ... (self: { inherit (self.extras) extraThing; })
```

These extras are also available downstream without being built by
default. This is achieved with `passthru`.
---
 pkgs/build-support/agda/default.nix | 39 +++++++++++++++++------------
 1 file changed, 23 insertions(+), 16 deletions(-)

diff --git a/pkgs/build-support/agda/default.nix b/pkgs/build-support/agda/default.nix
index 6e9aef5499aa..69c4897d1a4b 100644
--- a/pkgs/build-support/agda/default.nix
+++ b/pkgs/build-support/agda/default.nix
@@ -22,6 +22,9 @@ in
         propagatedBuildInputs = filter (y : ! (y == null)) x.propagatedBuildInputs;
         propagatedUserEnvPkgs = filter (y : ! (y == null)) x.propagatedUserEnvPkgs;
         everythingFile = if x.everythingFile == "" then "Everything.agda" else x.everythingFile;
+
+        passthru = { inherit (x) extras; };
+        extras = null;
       };
 
       defaults = self : {
@@ -63,25 +66,11 @@ in
                       ++ [ "." ];
         buildFlags = unwords (map (x: "-i " + x) self.includeDirs);
 
-        # We expose this as a mere convenience for any tools.
-        AGDA_PACKAGE_PATH = concatMapStrings (x: x + ":") self.buildDependsAgdaShareAgda;
-
-        # Makes a wrapper available to the user. Very useful in
-        # nix-shell where all dependencies are -i'd.
-        agdaWrapper = writeScriptBin "agda" ''
-          ${Agda}/bin/agda ${self.buildFlags} "$@"
-        '';
-
-        # configurePhase is idempotent
-        configurePhase = ''
-          runHook preConfigure
-          export PATH="${self.agdaWrapper}/bin:$PATH"
-          runHook postConfigure
-        '';
+        agdaWithArgs = "${Agda}/bin/agda ${self.buildFlags}";
 
         buildPhase = ''
           runHook preBuild
-          ${Agda}/bin/agda ${self.buildFlags} ${self.everythingFile}
+          ${self.agdaWithArgs} ${self.everythingFile}
           runHook postBuild
         '';
 
@@ -91,6 +80,24 @@ in
           cp -pR ${unwords self.sourceDirectories} ${mapInside self.topSourceDirectories} $out/share/agda
           runHook postInstall
         '';
+
+        # Optionally-built conveniences
+        extras = {
+          # Makes a wrapper available to the user. Very useful in
+          # nix-shell where all dependencies are -i'd.
+          agdaWrapper = writeScriptBin "agda" ''
+            ${self.agdaWithArgs} "$@"
+          '';
+
+          # Use this to stick `agdaWrapper` at the front of the PATH:
+          #
+          # agda.mkDerivation (self: { PATH = self.extras.agdaWrapperPATH; })
+          #
+          # Not sure this is the best way to handle conflicts....
+          agdaWrapperPATH = "${self.extras.agdaWrapper}/bin:$PATH";
+
+          AGDA_PACKAGE_PATH = concatMapStrings (x: x + ":") self.buildDependsAgdaShareAgda;
+        };
       };
     in stdenv.mkDerivation
          (postprocess (let super = defaults self // args self;