Disambiguate Python-keyword-named modules (#326)

E.g. import.proto turns into import_.py, not import.py
This allows the module to be imported via the normal import mechanisms.

Author: software-dov

packages/gapic-generator/gapic/schema/api.py

@@ -19,9 +19,11 @@
 
 import collections
 import dataclasses
+import keyword
+import os
 import sys
 from itertools import chain
-from typing import Callable, Dict, FrozenSet, Mapping, Sequence, Set, Tuple
+from typing import Callable, Container, Dict, FrozenSet, Mapping, Sequence, Set, Tuple
 
 from google.api_core import exceptions  # type: ignore
 from google.longrunning import operations_pb2  # type: ignore
@@ -204,10 +206,24 @@ def build(cls,
             file_descriptors,
         ), opts=opts)
 
+        def disambiguate_keyword_fname(
+                full_path: str,
+                visited_names: Container[str]) -> str:
+            path, fname = os.path.split(full_path)
+            name, ext = os.path.splitext(fname)
+            if name in keyword.kwlist or full_path in visited_names:
+                name += "_"
+                full_path = os.path.join(path, name + ext)
+                if full_path in visited_names:
+                    return disambiguate_keyword_fname(full_path, visited_names)
+
+            return full_path
+
         # Iterate over each FileDescriptorProto and fill out a Proto
         # object describing it, and save these to the instance.
         protos: Dict[str, Proto] = {}
         for fd in file_descriptors:
+            fd.name = disambiguate_keyword_fname(fd.name, protos)
             protos[fd.name] = _ProtoBuilder(
                 file_descriptor=fd,
                 file_to_generate=fd.package.startswith(package),

packages/gapic-generator/tests/unit/schema/test_api.py

@@ -142,6 +142,43 @@ def test_proto_names():
     assert proto.disambiguate('foo') == '_foo'
 
 
+def test_proto_keyword_fname():
+    # Protos with filenames that happen to be python keywords
+    # cannot be directly imported.
+    # Check that the file names are unspecialized when building the API object.
+    fd = (
+        make_file_pb2(
+            name='import.proto',
+            package='google.keywords.v1',
+            messages=(make_message_pb2(name='ImportRequest', fields=()),),
+        ),
+        make_file_pb2(
+            name='import_.proto',
+            package='google.keywords.v1',
+            messages=(make_message_pb2(name='ImportUnderRequest', fields=()),),
+        ),
+        make_file_pb2(
+            name='class_.proto',
+            package='google.keywords.v1',
+            messages=(make_message_pb2(name='ClassUnderRequest', fields=()),),
+        ),
+        make_file_pb2(
+            name='class.proto',
+            package='google.keywords.v1',
+            messages=(make_message_pb2(name='ClassRequest', fields=()),),
+        )
+    )
+
+    # We can't create new collisions, so check that renames cascade.
+    api_schema = api.API.build(fd, package='google.keywords.v1')
+    assert set(api_schema.protos.keys()) == {
+        'import_.proto',
+        'import__.proto',
+        'class_.proto',
+        'class__.proto',
+    }
+
+
 def test_proto_names_import_collision():
     # Put together a couple of minimal protos.
     fd = (