Fix typing and datetime imports not being present for service method type annotations

src/betterproto/plugin/models.py

@@ -324,17 +324,7 @@ def __post_init__(self) -> None:
         # Add field to message
         self.parent.fields.append(self)
         # Check for new imports
-        annotation = self.annotation
-        if "Optional[" in annotation:
-            self.output_file.typing_imports.add("Optional")
-        if "List[" in annotation:
-            self.output_file.typing_imports.add("List")
-        if "Dict[" in annotation:
-            self.output_file.typing_imports.add("Dict")
-        if "timedelta" in annotation:
-            self.output_file.datetime_imports.add("timedelta")
-        if "datetime" in annotation:
-            self.output_file.datetime_imports.add("datetime")
+        self.add_imports_to(self.output_file)
         super().__post_init__()  # call FieldCompiler-> MessageCompiler __post_init__
 
     def get_field_string(self, indent: int = 4) -> str:
@@ -356,6 +346,33 @@ def betterproto_field_args(self) -> List[str]:
             args.append(f"wraps={self.field_wraps}")
         return args
 
+    @property
+    def datetime_imports(self) -> Set[str]:
+        imports = set()
+        annotation = self.annotation
+        # FIXME: false positives - e.g. `MyDatetimedelta`
+        if "timedelta" in annotation:
+            imports.add("timedelta")
+        if "datetime" in annotation:
+            imports.add("datetime")
+        return imports
+
+    @property
+    def typing_imports(self) -> Set[str]:
+        imports = set()
+        annotation = self.annotation
+        if "Optional[" in annotation:
+            imports.add("Optional")
+        if "List[" in annotation:
+            imports.add("List")
+        if "Dict[" in annotation:
+            imports.add("Dict")
+        return imports
+
+    def add_imports_to(self, output_file: OutputTemplate) -> None:
+        output_file.datetime_imports.update(self.datetime_imports)
+        output_file.typing_imports.update(self.typing_imports)
+
     @property
     def field_wraps(self) -> Optional[str]:
         """Returns betterproto wrapped field type or None."""
@@ -577,11 +594,10 @@ def __post_init__(self) -> None:
         # Add method to service
         self.parent.methods.append(self)
 
-        # Check for Optional import
+        # Check for imports
         if self.py_input_message:
             for f in self.py_input_message.fields:
-                if f.default_value_string == "None":
-                    self.output_file.typing_imports.add("Optional")
+                f.add_imports_to(self.output_file)
         if "Optional" in self.py_output_message_type:
             self.output_file.typing_imports.add("Optional")
         self.mutable_default_args  # ensure this is called before rendering

tests/inputs/config.py

@@ -14,6 +14,7 @@
     "googletypes_response",
     "googletypes_response_embedded",
     "service",
+    "service_separate_packages",
     "import_service_input_message",
     "googletypes_service_returns_empty",
     "googletypes_service_returns_googletype",

tests/inputs/service_separate_packages/messages.proto

@@ -0,0 +1,31 @@
+syntax = "proto3";
+
+import "google/protobuf/duration.proto";
+import "google/protobuf/timestamp.proto";
+
+package things.messages;
+
+message DoThingRequest {
+  string name = 1;
+
+  // use `repeated` so we can check if `List` is correctly imported
+  repeated string comments = 2;
+
+  // use google types `timestamp` and `duration` so we can check
+  // if everything from `datetime` is correctly imported
+  google.protobuf.Timestamp when = 3;
+  google.protobuf.Duration duration = 4;
+}
+
+message DoThingResponse {
+  repeated string names = 1;
+}
+
+message GetThingRequest {
+  string name = 1;
+}
+
+message GetThingResponse {
+  string name = 1;
+  int32 version = 2;
+}

tests/inputs/service_separate_packages/service.proto

@@ -0,0 +1,12 @@
+syntax = "proto3";
+
+import "messages.proto";
+
+package things.service;
+
+service Test {
+  rpc DoThing (things.messages.DoThingRequest) returns (things.messages.DoThingResponse);
+  rpc DoManyThings (stream things.messages.DoThingRequest) returns (things.messages.DoThingResponse);
+  rpc GetThingVersions (things.messages.GetThingRequest) returns (stream things.messages.GetThingResponse);
+  rpc GetDifferentThings (stream things.messages.GetThingRequest) returns (stream things.messages.GetThingResponse);
+}