add stubs for trace (#1055)

stdlib/2and3/trace.pyi

@@ -0,0 +1,35 @@
+# Stubs for trace (Python 2 and 3)
+
+import os
+import sys
+import types
+from typing import Any, Callable, Mapping, Optional, Sequence, Text, Tuple, TypeVar, Union
+
+_T = TypeVar('_T')
+_localtrace = Callable[[types.FrameType, str, Any], Callable[..., Any]]
+
+if sys.version_info >= (3, 6):
+    _Path = Union[Text, os.PathLike]
+else:
+    _Path = Text
+
+class CoverageResults:
+    def update(self, other: CoverageResults) -> None: ...
+    def write_results(self, show_missing: bool = ..., summary: bool = ..., coverdir: Optional[_Path] = ...) -> None: ...
+    def write_results_file(self, path: _Path, lines: Sequence[str], lnotab: Any, lines_hit: Mapping[int, int], encoding: Optional[str] = ...) -> Tuple[int, int]: ...
+
+class Trace:
+    def __init__(self, count: int = ..., trace: int = ..., countfuncs: int = ..., countcallers: int = ...,
+                 ignoremods: Sequence[str] = ..., ignoredirs: Sequence[str] = ..., infile: Optional[_Path] = ...,
+                 outfile: Optional[_Path] = ..., timing: bool = ...) -> None: ...
+    def run(self, cmd: Union[str, types.CodeType]) -> None: ...
+    def runctx(self, cmd: Union[str, types.CodeType], globals: Optional[Mapping[str, Any]] = ..., locals: Optional[Mapping[str, Any]] = ...) -> None: ...
+    def runfunc(self, func: Callable[..., _T], *args: Any, **kw: Any) -> _T: ...
+    def file_module_function_of(self, frame: types.FrameType) -> Tuple[str, Optional[str], str]: ...
+    def globaltrace_trackcallers(self, frame: types.FrameType, why: str, arg: Any) -> None: ...
+    def globaltrace_countfuncs(self, frame: types.FrameType, why: str, arg: Any) -> None: ...
+    def globaltrace_lt(self, frame: types.FrameType, why: str, arg: Any) -> None: ...
+    def localtrace_trace_and_count(self, frame: types.FrameType, why: str, arg: Any) -> _localtrace: ...
+    def localtrace_trace(self, frame: types.FrameType, why: str, arg: Any) -> _localtrace: ...
+    def localtrace_count(self, frame: types.FrameType, why: str, arg: Any) -> _localtrace: ...
+    def results(self) -> CoverageResults: ...