]> git.madduck.net Git - etc/vim.git/blobdiff - src/black/concurrency.py

madduck's git repository

Every one of the projects in this repository is available at the canonical URL git://git.madduck.net/madduck/pub/<projectpath> — see each project's metadata for the exact URL.

All patches and comments are welcome. Please squash your changes to logical commits before using git-format-patch and git-send-email to patches@git.madduck.net. If you'd read over the Git project's submission guidelines and adhered to them, I'd be especially grateful.

SSH access, as well as push access can be individually arranged.

If you use my repositories frequently, consider adding the following snippet to ~/.gitconfig and using the third clone URL listed for each project:

[url "git://git.madduck.net/madduck/"]
  insteadOf = madduck:

tomli: Don't worry about specific alpha releases (#3448)
[etc/vim.git] / src / black / concurrency.py
index 69d79f534e82fc32267e61a1a10e319ca51585bd..1598f51e43f5a08b4ed428ebb15413798a0e3991 100644 (file)
@@ -1,9 +1,26 @@
+"""
+Formatting many files at once via multiprocessing. Contains entrypoint and utilities.
+
+NOTE: this module is only imported if we need to format several files at once.
+"""
+
 import asyncio
 import logging
+import os
+import signal
 import sys
-from typing import Any, Iterable
+from concurrent.futures import Executor, ProcessPoolExecutor, ThreadPoolExecutor
+from multiprocessing import Manager
+from pathlib import Path
+from typing import Any, Iterable, Optional, Set
+
+from mypy_extensions import mypyc_attr
 
+from black import WriteBack, format_file_in_place
+from black.cache import Cache, filter_cached, read_cache, write_cache
+from black.mode import Mode
 from black.output import err
+from black.report import Changed, Report
 
 
 def maybe_install_uvloop() -> None:
@@ -11,7 +28,6 @@ def maybe_install_uvloop() -> None:
 
     This is called only from command-line entry points to avoid
     interfering with the parent process if Black is used as a library.
-
     """
     try:
         import uvloop
@@ -31,20 +47,14 @@ def cancel(tasks: Iterable["asyncio.Task[Any]"]) -> None:
 def shutdown(loop: asyncio.AbstractEventLoop) -> None:
     """Cancel all pending tasks on `loop`, wait for them, and close the loop."""
     try:
-        if sys.version_info[:2] >= (3, 7):
-            all_tasks = asyncio.all_tasks
-        else:
-            all_tasks = asyncio.Task.all_tasks
         # This part is borrowed from asyncio/runners.py in Python 3.7b2.
-        to_cancel = [task for task in all_tasks(loop) if not task.done()]
+        to_cancel = [task for task in asyncio.all_tasks(loop) if not task.done()]
         if not to_cancel:
             return
 
         for task in to_cancel:
             task.cancel()
-        loop.run_until_complete(
-            asyncio.gather(*to_cancel, loop=loop, return_exceptions=True)
-        )
+        loop.run_until_complete(asyncio.gather(*to_cancel, return_exceptions=True))
     finally:
         # `concurrent.futures.Future` objects cannot be cancelled once they
         # are already running. There might be some when the `shutdown()` happened.
@@ -52,3 +62,126 @@ def shutdown(loop: asyncio.AbstractEventLoop) -> None:
         cf_logger = logging.getLogger("concurrent.futures")
         cf_logger.setLevel(logging.CRITICAL)
         loop.close()
+
+
+# diff-shades depends on being to monkeypatch this function to operate. I know it's
+# not ideal, but this shouldn't cause any issues ... hopefully. ~ichard26
+@mypyc_attr(patchable=True)
+def reformat_many(
+    sources: Set[Path],
+    fast: bool,
+    write_back: WriteBack,
+    mode: Mode,
+    report: Report,
+    workers: Optional[int],
+) -> None:
+    """Reformat multiple files using a ProcessPoolExecutor."""
+    maybe_install_uvloop()
+
+    executor: Executor
+    if workers is None:
+        workers = os.cpu_count() or 1
+    if sys.platform == "win32":
+        # Work around https://bugs.python.org/issue26903
+        workers = min(workers, 60)
+    try:
+        executor = ProcessPoolExecutor(max_workers=workers)
+    except (ImportError, NotImplementedError, OSError):
+        # we arrive here if the underlying system does not support multi-processing
+        # like in AWS Lambda or Termux, in which case we gracefully fallback to
+        # a ThreadPoolExecutor with just a single worker (more workers would not do us
+        # any good due to the Global Interpreter Lock)
+        executor = ThreadPoolExecutor(max_workers=1)
+
+    loop = asyncio.new_event_loop()
+    asyncio.set_event_loop(loop)
+    try:
+        loop.run_until_complete(
+            schedule_formatting(
+                sources=sources,
+                fast=fast,
+                write_back=write_back,
+                mode=mode,
+                report=report,
+                loop=loop,
+                executor=executor,
+            )
+        )
+    finally:
+        try:
+            shutdown(loop)
+        finally:
+            asyncio.set_event_loop(None)
+        if executor is not None:
+            executor.shutdown()
+
+
+async def schedule_formatting(
+    sources: Set[Path],
+    fast: bool,
+    write_back: WriteBack,
+    mode: Mode,
+    report: "Report",
+    loop: asyncio.AbstractEventLoop,
+    executor: "Executor",
+) -> None:
+    """Run formatting of `sources` in parallel using the provided `executor`.
+
+    (Use ProcessPoolExecutors for actual parallelism.)
+
+    `write_back`, `fast`, and `mode` options are passed to
+    :func:`format_file_in_place`.
+    """
+    cache: Cache = {}
+    if write_back not in (WriteBack.DIFF, WriteBack.COLOR_DIFF):
+        cache = read_cache(mode)
+        sources, cached = filter_cached(cache, sources)
+        for src in sorted(cached):
+            report.done(src, Changed.CACHED)
+    if not sources:
+        return
+
+    cancelled = []
+    sources_to_cache = []
+    lock = None
+    if write_back in (WriteBack.DIFF, WriteBack.COLOR_DIFF):
+        # For diff output, we need locks to ensure we don't interleave output
+        # from different processes.
+        manager = Manager()
+        lock = manager.Lock()
+    tasks = {
+        asyncio.ensure_future(
+            loop.run_in_executor(
+                executor, format_file_in_place, src, fast, mode, write_back, lock
+            )
+        ): src
+        for src in sorted(sources)
+    }
+    pending = tasks.keys()
+    try:
+        loop.add_signal_handler(signal.SIGINT, cancel, pending)
+        loop.add_signal_handler(signal.SIGTERM, cancel, pending)
+    except NotImplementedError:
+        # There are no good alternatives for these on Windows.
+        pass
+    while pending:
+        done, _ = await asyncio.wait(pending, return_when=asyncio.FIRST_COMPLETED)
+        for task in done:
+            src = tasks.pop(task)
+            if task.cancelled():
+                cancelled.append(task)
+            elif task.exception():
+                report.failed(src, str(task.exception()))
+            else:
+                changed = Changed.YES if task.result() else Changed.NO
+                # If the file was written back or was successfully checked as
+                # well-formatted, store this information in the cache.
+                if write_back is WriteBack.YES or (
+                    write_back is WriteBack.CHECK and changed is Changed.NO
+                ):
+                    sources_to_cache.append(src)
+                report.done(src, changed)
+    if cancelled:
+        await asyncio.gather(*cancelled, return_exceptions=True)
+    if sources_to_cache:
+        write_cache(cache, sources_to_cache, mode)