Small code improvements

Co-authored-by: Andrea Leopardi <[email protected]>

Author: v0idpwn

lib/protobuf/json/encode.ex

@@ -302,8 +302,12 @@ defmodule Protobuf.JSON.Encode do
   defp maybe_repeat(%{repeated?: true}, val, fun), do: Enum.map(val, fun)
 
   defp default?(_prop, +0.0), do: true
-  defp default?(_prop, -0.0), do: false
-  defp default?(_prop, value) when value in [nil, 0, false, [], "", %{}], do: true
+  defp default?(_prop, nil), do: true
+  defp default?(_prop, 0), do: true
+  defp default?(_prop, false), do: true
+  defp default?(_prop, []), do: true
+  defp default?(_prop, ""), do: true
+  defp default?(_prop, %{} = map) when map_size(map) == 0, do: true
   defp default?(%{type: {:enum, enum}}, key) when is_atom(key), do: enum.value(key) == 0
   defp default?(_prop, _value), do: false
 

test/protobuf/encoder_test.exs

@@ -171,9 +171,10 @@ defmodule Protobuf.EncoderTest do
     assert Encoder.encode(msg) == <<>>
   end
 
-  if :erlang.system_info(:otp_release) < ~c"27" do
+  if System.otp_release() < "27" do
     @tag :skip
   end
+
   test "skips float positive zero, but doesn't skip negative zero" do
     msg = %TestMsg.Foo{d: 0.0, n: 0.0}
     assert Encoder.encode(msg) == <<>>

test/protobuf/json/encode_test.exs

@@ -98,9 +98,10 @@ defmodule Protobuf.JSON.EncodeTest do
     assert encode(message) == %{"float" => "-Infinity", "double" => "-Infinity"}
   end
 
-  if :erlang.system_info(:otp_release) < ~c"27" do
+  if System.otp_release() < "27" do
     @tag :skip
   end
+
   test "encodes negative zero" do
     message = %Scalars{float: -0.0, double: -0.0}
     assert %{"float" => -0.0, "double" => -0.0} = encode(message)

test/test_helper.exs

@@ -51,7 +51,7 @@ defmodule Protobuf.TestHelpers do
 
   # This code is taken from Code.fetch_docs/1 in Elixir (v1.13 in particular).
   def fetch_docs_from_bytecode(bytecode) when is_binary(bytecode) do
-    docs_chunk = 'Docs'
+    docs_chunk = ~c"Docs"
     assert {:ok, {_module, [{^docs_chunk, bin}]}} = :beam_lib.chunks(bytecode, [docs_chunk])
     :erlang.binary_to_term(bin)
   end