Apply typing to all of pre-commit-hooks

pre_commit_hooks/requirements_txt_fixer.py

@@ -1,6 +1,10 @@
 from __future__ import print_function
 
 import argparse
+from typing import IO
+from typing import List
+from typing import Optional
+from typing import Sequence
 
 
 PASS = 0
@@ -9,21 +13,23 @@ FAIL = 1
 
 class Requirement(object):
 
-    def __init__(self):
+    def __init__(self):  # type: () -> None
         super(Requirement, self).__init__()
-        self.value = None
-        self.comments = []
+        self.value = None  # type: Optional[bytes]
+        self.comments = []   # type: List[bytes]
 
     @property
-    def name(self):
+    def name(self):  # type: () -> bytes
+        assert self.value is not None, self.value
         if self.value.startswith(b'-e '):
             return self.value.lower().partition(b'=')[-1]
 
         return self.value.lower().partition(b'==')[0]
 
-    def __lt__(self, requirement):
+    def __lt__(self, requirement):  # type: (Requirement) -> int
         # \n means top of file comment, so always return True,
         # otherwise just do a string comparison with value.
+        assert self.value is not None, self.value
         if self.value == b'\n':
             return True
         elif requirement.value == b'\n':
@@ -32,10 +38,10 @@ class Requirement(object):
             return self.name < requirement.name
 
 
-def fix_requirements(f):
-    requirements = []
+def fix_requirements(f):  # type: (IO[bytes]) -> int
+    requirements = []  # type: List[Requirement]
     before = tuple(f)
-    after = []
+    after = []  # type: List[bytes]
 
     before_string = b''.join(before)
 
@@ -46,6 +52,7 @@ def fix_requirements(f):
     for line in before:
         # If the most recent requirement object has a value, then it's
         # time to start building the next requirement object.
+
         if not len(requirements) or requirements[-1].value is not None:
             requirements.append(Requirement())
 
@@ -78,6 +85,7 @@ def fix_requirements(f):
 
     for requirement in sorted(requirements):
         after.extend(requirement.comments)
+        assert requirement.value, requirement.value
         after.append(requirement.value)
     after.extend(rest)
 
@@ -92,7 +100,7 @@ def fix_requirements(f):
         return FAIL
 
 
-def fix_requirements_txt(argv=None):
+def main(argv=None):  # type: (Optional[Sequence[str]]) -> int
     parser = argparse.ArgumentParser()
     parser.add_argument('filenames', nargs='*', help='Filenames to fix')
     args = parser.parse_args(argv)
@@ -109,3 +117,7 @@ def fix_requirements_txt(argv=None):
             retv |= ret_for_file
 
     return retv
+
+
+if __name__ == '__main__':
+    exit(main())