chore(unit): add type annotations

weblate/trans/models/unit.py

@@ -55,6 +55,7 @@
 
 if TYPE_CHECKING:
     from collections.abc import Generator, Iterable
+    from datetime import datetime
 
     from weblate.auth.models import User
     from weblate.machinery.base import UnitMemoryResultDict
@@ -564,33 +565,33 @@ def store_old_unit(self, unit) -> None:
         }
 
     @property
-    def approved(self):
+    def approved(self) -> bool:
         return self.state == STATE_APPROVED
 
     @property
-    def translated(self):
+    def translated(self) -> bool:
         return self.state >= STATE_TRANSLATED
 
     @property
-    def readonly(self):
+    def readonly(self) -> bool:
         return self.state == STATE_READONLY
 
     @property
-    def fuzzy(self):
+    def fuzzy(self) -> bool:
         return self.state == STATE_FUZZY
 
     @property
-    def has_failing_check(self):
+    def has_failing_check(self) -> bool:
         return bool(self.active_checks)
 
     @property
-    def has_comment(self):
+    def has_comment(self) -> bool:
         # Use bool here as unresolved_comments might be list
         # or a queryset (from prefetch)
         return bool(self.unresolved_comments)
 
     @property
-    def has_suggestion(self):
+    def has_suggestion(self) -> bool:
         return bool(self.suggestions)
 
     def source_unit_save(self) -> None:
@@ -1067,7 +1068,7 @@ def propagate(self, user: User, change_action=None, author=None, request=None):
             result = True
         return result
 
-    def commit_if_pending(self, author) -> None:
+    def commit_if_pending(self, author: User) -> None:
         """Commit possible previous changes on this unit."""
         if self.pending:
             change_author = self.get_last_content_change()[0]
@@ -1168,7 +1169,9 @@ def save_backend(
 
         return True
 
-    def update_source_units(self, previous_source, user: User, author) -> None:
+    def update_source_units(
+        self, previous_source: str, user: User, author: User | None
+    ) -> None:
         """
         Update source for units within same component.
 
@@ -1229,7 +1232,7 @@ def generate_change(
         save: bool = True,
         old: str | None = None,
         target: str | None = None,
-    ):
+    ) -> Change:
         """Create Change entry for saving unit."""
         # Notify about new contributor
         if (
@@ -1279,12 +1282,12 @@ def generate_change(
         return change
 
     @cached_property
-    def suggestions(self):
+    def suggestions(self) -> models.QuerySet[Suggestion]:
         """Return all suggestions for this unit."""
         return self.suggestion_set.order()
 
     @cached_property
-    def all_checks(self):
+    def all_checks(self) -> models.QuerySet[Check]:
         result = self.check_set.all()
         # Force fetching
         list(result)
@@ -1295,20 +1298,20 @@ def clear_checks_cache(self) -> None:
             del self.__dict__["all_checks"]
 
     @property
-    def all_checks_names(self):
+    def all_checks_names(self) -> set[str]:
         return {check.name for check in self.all_checks}
 
     @property
-    def dismissed_checks(self):
+    def dismissed_checks(self) -> list[Check]:
         return [check for check in self.all_checks if check.dismissed]
 
     @property
-    def active_checks(self):
+    def active_checks(self) -> list[Check]:
         """Return all active (not ignored) checks for this unit."""
         return [check for check in self.all_checks if not check.dismissed]
 
     @cached_property
-    def all_comments(self):
+    def all_comments(self) -> models.QuerySet[Comment]:
         """Return list of target comments."""
         if self.is_source:
             # Add all comments on translation on source string comment
@@ -1319,7 +1322,7 @@ def all_comments(self):
         return Comment.objects.filter(query).prefetch_related("unit", "user").order()
 
     @cached_property
-    def unresolved_comments(self):
+    def unresolved_comments(self) -> list[Comment]:
         return [
             comment
             for comment in self.all_comments
@@ -1423,7 +1426,7 @@ def run_checks(self, propagate: bool | None = None) -> None:  # noqa: C901
         if not self.is_batch_update and (create or old_checks):
             self.translation.invalidate_cache()
 
-    def nearby(self, count: int):
+    def nearby(self, count: int) -> models.QuerySet[Unit]:
         """Return list of nearby messages based on location."""
         if self.position == 0:
             return Unit.objects.none()
@@ -1442,7 +1445,7 @@ def nearby(self, count: int):
             list(result)
             return result
 
-    def nearby_keys(self, count):
+    def nearby_keys(self, count: int) -> Iterable[Unit]:
         # Do not show nearby keys on bilingual
         if not self.translation.component.has_template():
             return []
@@ -1462,7 +1465,7 @@ def nearby_keys(self, count):
             list(result)
             return result
 
-    def variants(self):
+    def variants(self) -> Iterable[Unit]:
         if not self.variant:
             return []
         return (
@@ -1482,7 +1485,7 @@ def translate(
         author=None,
         request=None,
         add_alternative: bool = False,
-    ):
+    ) -> bool:
         """
         Store new translation of a unit.
 
@@ -1670,11 +1673,11 @@ def get_max_length(self):
 
         return fallback
 
-    def get_target_hash(self):
+    def get_target_hash(self) -> int:
         return calculate_hash(self.target)
 
     @cached_property
-    def content_hash(self):
+    def content_hash(self) -> int:
         return calculate_hash(self.source, self.context)
 
     @cached_property
@@ -1686,7 +1689,7 @@ def recent_content_changes(self):
         """
         return self.change_set.content().select_related("author").order_by("-timestamp")
 
-    def get_last_content_change(self, silent=False):
+    def get_last_content_change(self, silent: bool = False) -> tuple[User, datetime]:
         """
         Get last content change metadata.