Started adding some quickcheck tests.

eqct/Makefile

@@ -0,0 +1,12 @@
+include ../support/include.mk
+
+all: $(EBIN_FILES)
+
+clean:
+	rm -rf $(EBIN_FILES) erl_crash.dump simple_pb.*
+
+test: $(MODULES)
+
+./$(MODULES):
+	@echo "Running tests for $@"
+	erl -pa ../ebin -run $@ start -run init stop -noshell

eqct/eqct_protobuffs_basic.erl

@@ -0,0 +1,20 @@
+-module(eqct_protobuffs_basic).
+-compile(export_all). 
+-include_lib("eqc/include/eqc.hrl").
+
+int32() -> 
+    ?FORALL(
+        Xs,
+        nat(), 
+        {{1, Xs}, <<>>} == protobuffs:decode(list_to_binary(protobuffs:encode(1, Xs, int32)), int32)
+    ).
+
+string() ->
+    ?FORALL(
+        Xs,
+        list(char()), 
+        (fun(Var) ->
+            {{1, Foo}, <<>>} = protobuffs:decode(list_to_binary(protobuffs:encode(1, Var, string)), string),
+            Foo == list_to_binary(Var)
+        end)(Xs)
+    ).