From a91f25a7b0f9bd95d9e9558b45c79d95d84ef2f4 Mon Sep 17 00:00:00 2001
From: Kev <fisherk.work@gmail.com>
Date: Mon, 16 Oct 2023 19:22:01 -0400
Subject: [PATCH] clean up some types to avoid type narrowing

---
 src/sentry/snuba/metrics/extraction.py | 13 +++++++------
 1 file changed, 7 insertions(+), 6 deletions(-)

diff --git a/src/sentry/snuba/metrics/extraction.py b/src/sentry/snuba/metrics/extraction.py
index 7f0cd93f203d08..e7164d18ba086f 100644
--- a/src/sentry/snuba/metrics/extraction.py
+++ b/src/sentry/snuba/metrics/extraction.py
@@ -579,10 +579,10 @@ def _deep_sorted(value: Union[Any, Dict[Any, Any]]) -> Union[Any, Dict[Any, Any]
         return value
 
 
-TagsSpecsGenerator = Callable[[Project, Optional[str]], List[TagSpec]]
+TagsSpecsGenerator = Callable[[Project, Optional[Sequence[str]]], List[TagSpec]]
 
 
-def failure_tag_spec(_1: Project, _2: Optional[str]) -> List[TagSpec]:
+def failure_tag_spec(_1: Project, _2: Optional[Sequence[str]]) -> List[TagSpec]:
     """This specification tags transactions with a boolean saying if it failed."""
     return [
         {
@@ -674,11 +674,12 @@ class OnDemandMetricSpec:
 
     # Private fields.
     _metric_type: str
-    _arguments: Optional[Sequence[str]]
+    _arguments: Sequence[str]
 
     def __init__(self, field: str, query: str):
         self.field = field
         self.query = query
+        self._arguments = []
         self._eager_process()
 
     def _eager_process(self):
@@ -686,7 +687,7 @@ def _eager_process(self):
 
         self.op = op
         self._metric_type = metric_type
-        self._arguments = arguments
+        self._arguments = arguments or []
 
     @property
     def field_to_extract(self):
@@ -773,7 +774,7 @@ def to_metric_spec(self, project: Project) -> MetricSpec:
 
         return metric_spec
 
-    def _process_field(self) -> Tuple[MetricOperationType, str, Optional[list[str]]]:
+    def _process_field(self) -> Tuple[MetricOperationType, str, Optional[Sequence[str]]]:
         parsed_field = self._parse_field(self.field)
         if parsed_field is None:
             raise Exception(f"Unable to parse the field {self.field}")
@@ -829,7 +830,7 @@ def _aggregate_conditions(parsed_field) -> Optional[RuleCondition]:
     @staticmethod
     def _parse_arguments(
         op: MetricOperationType, metric_type: str, parsed_field: FieldParsingResult
-    ) -> Optional[list[str]]:
+    ) -> Optional[Sequence[str]]:
         requires_arguments = metric_type in ["s", "d"] or op in ["on_demand_apdex"]
         if not requires_arguments:
             return None