Allow specifying meta for buildHex and buildErlang.

Adds "meta" for meck package as a test.

pkgs/development/erlang-modules/build-erlang.nix

@@ -3,6 +3,7 @@
 { name, version
 , buildInputs ? [], erlangDeps ? []
 , postPatch ? ""
+, meta ? {}
 , ... }@attrs:
 
 with stdenv.lib;
@@ -53,6 +54,10 @@ stdenv.mkDerivation (attrs // {
     runHook postInstall
   '';
 
+  meta = {
+    inherit (erlang.meta) platforms;
+  } // meta;
+
   passthru = {
     packageName = name;
     inherit erlangDeps;

pkgs/development/erlang-modules/build-hex.nix

@@ -6,6 +6,7 @@
 , buildInputs ? [], erlangDeps ? [], pluginDeps ? []
 , postPatch ? ""
 , compilePorts ? false
+, meta ? {}
 , ... }@attrs:
 
 with stdenv.lib;
@@ -88,6 +89,10 @@ stdenv.mkDerivation (attrs // {
     sha256 = sha256;
   };
 
+  meta = {
+    inherit (erlang.meta) platforms;
+  } // meta;
+
   passthru = {
     packageName = name;
     inherit erlangDeps;

pkgs/development/erlang-modules/hex/meck.nix

@@ -1,7 +1,13 @@
-{ buildHex }:
+{ stdenv, buildHex }:
 
 buildHex {
   name = "meck";
   version = "0.8.3";
   sha256 = "1dh2rhks1xly4f49x89vbhsk8fgwkx5zqp0n98mnng8rs1rkigak";
+
+  meta = {
+    description = "A mocking framework for Erlang";
+    homepage = "https://github.com/eproxus/meck";
+    license = stdenv.lib.licenses.apsl20;
+  };
 }