overrides: Pin pip to 20.2.4 to work around #244

Author: adisbladis

overrides.nix

@@ -654,6 +654,23 @@ self: super:
     }
   );
 
+  # Work around https://github.com/nix-community/poetry2nix/issues/244
+  # where git deps are not picked up as they should
+  pip = if lib.versionAtLeast super.pip.version "20.3" then super.pip.overridePythonAttrs (old: let
+    pname = "pip";
+    version = "20.2.4";
+  in {
+    name = pname + "-" + version;
+    inherit version;
+    src = pkgs.fetchFromGitHub {
+     owner = "pypa";
+     repo = pname;
+     rev = version;
+     sha256 = "eMVV4ftgV71HLQsSeaOchYlfaJVgzNrwUynn3SA1/Do=";
+     name = "${pname}-${version}-source";
+   };
+  }) else super.pip;
+
   poetry-core = super.poetry-core.overridePythonAttrs (old: {
     # "Vendor" dependencies (for build-system support)
     postPatch = ''