add type annotations for Tiger import function

nominatim/tools/tiger_data.py

@@ -7,6 +7,7 @@
 """
 Functions for importing tiger data and handling tarbar and directory files
 """
+from typing import Any, TextIO, List, Union, cast
 import csv
 import io
 import logging
@@ -15,11 +16,13 @@ import tarfile
 
 from psycopg2.extras import Json
 
+from nominatim.config import Configuration
 from nominatim.db.connection import connect
 from nominatim.db.async_connection import WorkerPool
 from nominatim.db.sql_preprocessor import SQLPreprocessor
 from nominatim.errors import UsageError
 from nominatim.data.place_info import PlaceInfo
+from nominatim.tokenizer.base import AbstractAnalyzer, AbstractTokenizer
 
 LOG = logging.getLogger()
 
@@ -28,9 +31,9 @@ class TigerInput:
         either be in a directory or gzipped together in a tar file.
     """
 
-    def __init__(self, data_dir):
+    def __init__(self, data_dir: str) -> None:
         self.tar_handle = None
-        self.files = []
+        self.files: List[Union[str, tarfile.TarInfo]] = []
 
         if data_dir.endswith('.tar.gz'):
             try:
@@ -50,33 +53,36 @@ class TigerInput:
             LOG.warning("Tiger data import selected but no files found at %s", data_dir)
 
 
-    def __enter__(self):
+    def __enter__(self) -> 'TigerInput':
         return self
 
 
-    def __exit__(self, exc_type, exc_val, exc_tb):
+    def __exit__(self, exc_type: Any, exc_val: Any, exc_tb: Any) -> None:
         if self.tar_handle:
             self.tar_handle.close()
             self.tar_handle = None
 
 
-    def next_file(self):
+    def next_file(self) -> TextIO:
         """ Return a file handle to the next file to be processed.
             Raises an IndexError if there is no file left.
         """
         fname = self.files.pop(0)
 
         if self.tar_handle is not None:
-            return io.TextIOWrapper(self.tar_handle.extractfile(fname))
+            extracted = self.tar_handle.extractfile(fname)
+            assert extracted is not None
+            return io.TextIOWrapper(extracted)
 
-        return open(fname, encoding='utf-8')
+        return open(cast(str, fname), encoding='utf-8')
 
 
-    def __len__(self):
+    def __len__(self) -> int:
         return len(self.files)
 
 
-def handle_threaded_sql_statements(pool, fd, analyzer):
+def handle_threaded_sql_statements(pool: WorkerPool, fd: TextIO,
+                                   analyzer: AbstractAnalyzer) -> None:
     """ Handles sql statement with multiplexing
     """
     lines = 0
@@ -101,7 +107,8 @@ def handle_threaded_sql_statements(pool, fd, analyzer):
             lines = 0
 
 
-def add_tiger_data(data_dir, config, threads, tokenizer):
+def add_tiger_data(data_dir: str, config: Configuration, threads: int,
+                   tokenizer: AbstractTokenizer) -> None:
     """ Import tiger data from directory or tar file `data dir`.
     """
     dsn = config.get_libpq_dsn()