From 092525616a476fcf955bc0645fbf90edbd7531fa Mon Sep 17 00:00:00 2001
From: David McFarland <corngood@gmail.com>
Date: Wed, 30 Dec 2020 10:17:43 -0400
Subject: [PATCH] msbuild: move extension path to app.config

This makes it work for things that load the assembly directly.
---
 pkgs/development/tools/build-managers/msbuild/default.nix | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/pkgs/development/tools/build-managers/msbuild/default.nix b/pkgs/development/tools/build-managers/msbuild/default.nix
index 2613f2d535e..da4d34f771a 100644
--- a/pkgs/development/tools/build-managers/msbuild/default.nix
+++ b/pkgs/development/tools/build-managers/msbuild/default.nix
@@ -54,6 +54,11 @@ stdenv.mkDerivation rec {
     })
   ];
 
+  postPatch = ''
+    sed -i -e "/<\/projectImportSearchPaths>/a <property name=\"MSBuildExtensionsPath\" value=\"$out/lib/mono/xbuild\"/>" \
+      src/MSBuild/app.config
+  '';
+
   buildPhase = ''
     # nuget would otherwise try to base itself in /homeless-shelter
     export HOME=$(pwd)/fake-home
@@ -93,7 +98,6 @@ stdenv.mkDerivation rec {
     ln -s ${mono}/lib/mono/msbuild/Current/bin/Roslyn $out/lib/mono/msbuild/Current/bin/Roslyn
 
     makeWrapper ${mono}/bin/mono $out/bin/msbuild \
-      --set MSBuildExtensionsPath $out/lib/mono/xbuild \
       --set-default MONO_GC_PARAMS "nursery-size=64m" \
       --add-flags "$out/lib/mono/msbuild/15.0/bin/MSBuild.dll"