Add internal classes and add type hints + mypy.

django_migration_linter/sql_analyser/analyser.py

@@ -1,6 +1,13 @@
+from __future__ import annotations
+
 import logging
+from typing import TYPE_CHECKING, Iterable, Type
+
+if TYPE_CHECKING:
+    from sql_analyser.base import Issue
 
 from django_migration_linter.sql_analyser import (
+    BaseAnalyser,
     MySqlAnalyser,
     PostgresqlAnalyser,
     SqliteAnalyser,
@@ -8,20 +15,22 @@ from django_migration_linter.sql_analyser import (
 
 logger = logging.getLogger("django_migration_linter")
 
-ANALYSER_STRING_MAPPING = {
+ANALYSER_STRING_MAPPING: dict[str, Type[BaseAnalyser]] = {
     "sqlite": SqliteAnalyser,
     "mysql": MySqlAnalyser,
     "postgresql": PostgresqlAnalyser,
 }
 
 
-def get_sql_analyser_class(database_vendor, analyser_string=None):
+def get_sql_analyser_class(
+    database_vendor: str, analyser_string: str | None = None
+) -> Type[BaseAnalyser]:
     if analyser_string:
         return get_sql_analyser_from_string(analyser_string)
     return get_sql_analyser_class_from_db_vendor(database_vendor)
 
 
-def get_sql_analyser_from_string(analyser_string):
+def get_sql_analyser_from_string(analyser_string: str) -> Type[BaseAnalyser]:
     if analyser_string not in ANALYSER_STRING_MAPPING:
         raise ValueError(
             "Unknown SQL analyser '{}'. Known values: '{}'".format(
@@ -32,7 +41,8 @@ def get_sql_analyser_from_string(analyser_string):
     return ANALYSER_STRING_MAPPING[analyser_string]
 
 
-def get_sql_analyser_class_from_db_vendor(database_vendor):
+def get_sql_analyser_class_from_db_vendor(database_vendor: str) -> Type[BaseAnalyser]:
+    sql_analyser_class: Type[BaseAnalyser]
     if "mysql" in database_vendor:
         sql_analyser_class = MySqlAnalyser
     elif "postgre" in database_vendor:
@@ -51,8 +61,10 @@ def get_sql_analyser_class_from_db_vendor(database_vendor):
 
 
 def analyse_sql_statements(
-    sql_analyser_class, sql_statements, exclude_migration_tests=None
-):
+    sql_analyser_class: Type[BaseAnalyser],
+    sql_statements: list[str],
+    exclude_migration_tests: Iterable[str] | None = None,
+) -> tuple[list[Issue], list[Issue], list[Issue]]:
     sql_analyser = sql_analyser_class(exclude_migration_tests)
     sql_analyser.analyse(sql_statements)
     return sql_analyser.errors, sql_analyser.ignored, sql_analyser.warnings