xgboost: Enable building on Darwin (#37046)

* xgboost: Enable building on Darwin

* Review feedback: pass `xgboost` to the python package

pkgs/development/python-modules/xgboost/default.nix

@@ -0,0 +1,35 @@
+{ stdenv
+, lib
+, pkgs
+, buildPythonPackage
+, nose
+, scipy
+, xgboost
+}:
+
+buildPythonPackage rec {
+  name = "xgboost-${version}";
+
+  inherit (xgboost) version src meta;
+
+  propagatedBuildInputs = [ scipy ];
+  checkInputs = [ nose ];
+
+  postPatch = let
+    libname = if stdenv.isDarwin then "libxgboost.dylib" else "libxgboost.so";
+
+  in ''
+    cd python-package
+
+    sed "s/CURRENT_DIR = os.path.dirname(__file__)/CURRENT_DIR = os.path.abspath(os.path.dirname(__file__))/g" -i setup.py
+    sed "/^LIB_PATH.*/a LIB_PATH = [os.path.relpath(LIB_PATH[0], CURRENT_DIR)]" -i setup.py
+    cat <<EOF >xgboost/libpath.py
+    def find_lib_path():
+      return ["${xgboost}/lib/${libname}"]
+    EOF
+  '';
+
+  postInstall = ''
+    rm -rf $out/xgboost
+  '';
+}