python-protobuf: enable python3 and enable py3 tests

- moved expression out of python-packages
- no significant changes how package is built except the supported
  python versions

1 files changed, 46 insertions, 0 deletions

diff --git a/pkgs/development/python-modules/protobuf.nix b/pkgs/development/python-modules/protobuf.nix
new file mode 100644
index 000000000000..8b9d1ddb03c4
--- /dev/null
+++ b/pkgs/development/python-modules/protobuf.nix
@@ -0,0 +1,46 @@
+{ stdenv, python, buildPythonPackage
+, protobuf, google_apputils
+, disabled, doCheck ? true }:
+
+with stdenv.lib;
+
+buildPythonPackage rec {
+  inherit (protobuf) name src;
+  inherit disabled doCheck;
+
+  propagatedBuildInputs = [ protobuf google_apputils ];
+  buildInputs = [ google_apputils ];
+
+  prePatch = ''
+    while [ ! -d python ]; do
+      cd *
+    done
+    cd python
+  '';
+
+  preConfigure = optionalString (versionAtLeast protobuf.version "2.6.0") ''
+    export PROTOCOL_BUFFERS_PYTHON_IMPLEMENTATION=cpp
+    export PROTOCOL_BUFFERS_PYTHON_IMPLEMENTATION_VERSION=2
+  '';
+
+  preBuild = optionalString (versionAtLeast protobuf.version "2.6.0") ''
+    ${python}/bin/${python.executable} setup.py build_ext --cpp_implementation
+  '';
+
+  installFlags = optional (versionAtLeast protobuf.version "2.6.0")
+    "--install-option='--cpp_implementation'";
+
+  # the _message.so isn't installed, so we'll do that manually.
+  # if someone can figure out a less hacky way to get the _message.so to
+  # install, please do replace this.
+  postInstall = optionalString (versionAtLeast protobuf.version "2.6.0") ''
+    cp -v $(find build -name "_message*") $out/${python.sitePackages}/google/protobuf/pyext
+  '';
+
+  meta = {
+    description = "Protocol Buffers are Google's data interchange format";
+    homepage = https://developers.google.com/protocol-buffers/;
+  };
+
+  passthru.protobuf = protobuf;
+}