Add mypy to CI and fix errors

mypy.ini

@@ -4,3 +4,6 @@ warn_unused_configs = True
 
 [mypy-backoff.*]
 ignore_missing_imports = True
+
+[mypy-facebook_business.*]
+ignore_missing_imports = True

pyproject.toml

@@ -22,6 +22,7 @@ facebook-business = "^19.0.0"
 [tool.poetry.dev-dependencies]
 pytest = ">=7.4.1"
 singer-sdk = {version = ">=0.27,<0.35", extras = ["testing"]}
+mypy = "^1.8.0"
 
 [tool.isort]
 profile = "black"

tap_facebook/streams/ad_insights.py

@@ -102,14 +102,17 @@ def _get_datatype(field: str) -> th.Type | None:
     @property
     @lru_cache  # noqa: B019
     def schema(self) -> dict:
-        properties: th.List[th.Property] = []
+        properties: list[th.Property] = []
         columns = list(AdsInsights.Field.__dict__)[1:]
         for field in columns:
             if field in EXCLUDED_FIELDS:
                 continue
             properties.append(th.Property(field, self._get_datatype(field)))
-        for breakdown in self._report_definition["breakdowns"]:
-            properties.append(th.Property(breakdown, th.StringType()))
+        breakdown_list = [
+            th.Property(breakdown, th.StringType())
+            for breakdown in self._report_definition["breakdowns"]
+        ]
+        properties.extend(breakdown_list)
         return th.PropertiesList(*properties).to_dict()
 
     def _initialize_client(self) -> None:
@@ -126,7 +129,7 @@ def _initialize_client(self) -> None:
             msg = f"Couldn't find account with id {account_id}"
             raise RuntimeError(msg)
 
-    def _run_job_to_completion(self, params: dict) -> th.Any:
+    def _run_job_to_completion(self, params: dict) -> t.Any:  # noqa: ANN401
         job = self.account.get_insights(
             params=params,
             is_async=True,

tap_facebook/streams/campaign.py

@@ -135,8 +135,8 @@ class CampaignStream(IncrementalFacebookStream):
     def post_process(
         self,
         row: dict,
-        context: dict | None,  # noqa: ARG002
-    ) -> dict:
+        context: dict | None = None,  # noqa: ARG002
+    ) -> dict | None:
         daily_budget = row.get("daily_budget")
         row["daily_budget"] = int(daily_budget) if daily_budget is not None else None
         return row

tap_facebook/streams/custom_audiences.py

@@ -36,6 +36,10 @@ class CustomAudiences(FacebookStream):
     def path(self) -> str:
         return f"/customaudiences?fields={self.columns}"
 
+    @path.setter
+    def path(self, new_value: str) -> None:
+        self._value = new_value
+
     @property
     def columns(self) -> list[str]:
         return [