Add basic support for all google.protobuf types

betterproto/plugin.py

@@ -88,6 +88,14 @@ def get_ref_type(
             cased = [stringcase.pascalcase(part) for part in parts]
             type_name = f'"{"".join(cased)}"'
 
+    # Use precompiled classes for google.protobuf.* objects
+    if type_name.startswith("google.protobuf.") and type_name.count(".") == 2:
+        type_name = type_name.rsplit(".", maxsplit=1)[1]
+        import_package = "betterproto.lib.google.protobuf"
+        import_alias = safe_snake_case(import_package)
+        imports.add(f"import {import_package} as {import_alias}")
+        return f"{import_alias}.{type_name}"
+
     if "." in type_name:
         # This is imported from another package. No need
         # to use a forward ref and we need to add the import.

betterproto/tests/inputs/googletypes/googletypes.json

@@ -1,5 +1,7 @@
 {
   "maybe": false,
   "ts": "1972-01-01T10:00:20.021Z",
-  "duration": "1.200s"
+  "duration": "1.200s",
+  "important": 10,
+  "empty": {}
 }

betterproto/tests/inputs/googletypes/googletypes.proto

@@ -3,10 +3,12 @@ syntax = "proto3";
 import "google/protobuf/duration.proto";
 import "google/protobuf/timestamp.proto";
 import "google/protobuf/wrappers.proto";
+import "google/protobuf/empty.proto";
 
 message Test {
   google.protobuf.BoolValue maybe = 1;
   google.protobuf.Timestamp ts = 2;
   google.protobuf.Duration duration = 3;
   google.protobuf.Int32Value important = 4;
+  google.protobuf.Empty empty = 5;
 }