From 865f536143e73da60f7c6b60924eb2472deb1cfe Mon Sep 17 00:00:00 2001
From: Terrance <4025899+Terrance@users.noreply.github.com>
Date: Sat, 9 May 2020 17:22:23 +0100
Subject: [PATCH] Handle ImportError from multiprocessing module (#1400)

Termux's Python environment doesn't provide sem_open, but fails with a
nested `ImportError` on import attempts:

    ImportError: cannot import name 'SemLock' from '_multiprocessing'

This updates the existing handling for AWS Lambda to catch both
`OSError` and `ImportError`.
---
 src/black/__init__.py | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/src/black/__init__.py b/src/black/__init__.py
index 3ab4bc7..41c688b 100644
--- a/src/black/__init__.py
+++ b/src/black/__init__.py
@@ -662,9 +662,9 @@ def reformat_many(
         worker_count = min(worker_count, 61)
     try:
         executor = ProcessPoolExecutor(max_workers=worker_count)
-    except OSError:
+    except (ImportError, OSError):
         # we arrive here if the underlying system does not support multi-processing
-        # like in AWS Lambda, in which case we gracefully fallback to
+        # like in AWS Lambda or Termux, in which case we gracefully fallback to
         # a ThreadPollExecutor with just a single worker (more workers would not do us
         # any good due to the Global Interpreter Lock)
         executor = ThreadPoolExecutor(max_workers=1)
-- 
2.39.2