Re-organize directory structure (#4971)

See discussion in #2491

Co-authored-by: Ivan Levkivskyi <ilevkivskyi@dropbox.com>

stdlib/selectors.pyi

@@ -0,0 +1,69 @@
+import sys
+from _typeshed import FileDescriptor, FileDescriptorLike
+from abc import ABCMeta, abstractmethod
+from typing import Any, List, Mapping, NamedTuple, Optional, Tuple
+
+_EventMask = int
+
+EVENT_READ: _EventMask
+EVENT_WRITE: _EventMask
+
+class SelectorKey(NamedTuple):
+    fileobj: FileDescriptorLike
+    fd: FileDescriptor
+    events: _EventMask
+    data: Any
+
+class BaseSelector(metaclass=ABCMeta):
+    @abstractmethod
+    def register(self, fileobj: FileDescriptorLike, events: _EventMask, data: Any = ...) -> SelectorKey: ...
+    @abstractmethod
+    def unregister(self, fileobj: FileDescriptorLike) -> SelectorKey: ...
+    def modify(self, fileobj: FileDescriptorLike, events: _EventMask, data: Any = ...) -> SelectorKey: ...
+    @abstractmethod
+    def select(self, timeout: Optional[float] = ...) -> List[Tuple[SelectorKey, _EventMask]]: ...
+    def close(self) -> None: ...
+    def get_key(self, fileobj: FileDescriptorLike) -> SelectorKey: ...
+    @abstractmethod
+    def get_map(self) -> Mapping[FileDescriptorLike, SelectorKey]: ...
+    def __enter__(self) -> BaseSelector: ...
+    def __exit__(self, *args: Any) -> None: ...
+
+class SelectSelector(BaseSelector):
+    def register(self, fileobj: FileDescriptorLike, events: _EventMask, data: Any = ...) -> SelectorKey: ...
+    def unregister(self, fileobj: FileDescriptorLike) -> SelectorKey: ...
+    def select(self, timeout: Optional[float] = ...) -> List[Tuple[SelectorKey, _EventMask]]: ...
+    def get_map(self) -> Mapping[FileDescriptorLike, SelectorKey]: ...
+
+if sys.platform != "win32":
+    class PollSelector(BaseSelector):
+        def register(self, fileobj: FileDescriptorLike, events: _EventMask, data: Any = ...) -> SelectorKey: ...
+        def unregister(self, fileobj: FileDescriptorLike) -> SelectorKey: ...
+        def select(self, timeout: Optional[float] = ...) -> List[Tuple[SelectorKey, _EventMask]]: ...
+        def get_map(self) -> Mapping[FileDescriptorLike, SelectorKey]: ...
+    class EpollSelector(BaseSelector):
+        def fileno(self) -> int: ...
+        def register(self, fileobj: FileDescriptorLike, events: _EventMask, data: Any = ...) -> SelectorKey: ...
+        def unregister(self, fileobj: FileDescriptorLike) -> SelectorKey: ...
+        def select(self, timeout: Optional[float] = ...) -> List[Tuple[SelectorKey, _EventMask]]: ...
+        def get_map(self) -> Mapping[FileDescriptorLike, SelectorKey]: ...
+
+class DevpollSelector(BaseSelector):
+    def fileno(self) -> int: ...
+    def register(self, fileobj: FileDescriptorLike, events: _EventMask, data: Any = ...) -> SelectorKey: ...
+    def unregister(self, fileobj: FileDescriptorLike) -> SelectorKey: ...
+    def select(self, timeout: Optional[float] = ...) -> List[Tuple[SelectorKey, _EventMask]]: ...
+    def get_map(self) -> Mapping[FileDescriptorLike, SelectorKey]: ...
+
+class KqueueSelector(BaseSelector):
+    def fileno(self) -> int: ...
+    def register(self, fileobj: FileDescriptorLike, events: _EventMask, data: Any = ...) -> SelectorKey: ...
+    def unregister(self, fileobj: FileDescriptorLike) -> SelectorKey: ...
+    def select(self, timeout: Optional[float] = ...) -> List[Tuple[SelectorKey, _EventMask]]: ...
+    def get_map(self) -> Mapping[FileDescriptorLike, SelectorKey]: ...
+
+class DefaultSelector(BaseSelector):
+    def register(self, fileobj: FileDescriptorLike, events: _EventMask, data: Any = ...) -> SelectorKey: ...
+    def unregister(self, fileobj: FileDescriptorLike) -> SelectorKey: ...
+    def select(self, timeout: Optional[float] = ...) -> List[Tuple[SelectorKey, _EventMask]]: ...
+    def get_map(self) -> Mapping[FileDescriptorLike, SelectorKey]: ...