trim usage of to-be-removed "future" library

src/allmydata/scripts/debug.py

@@ -2,8 +2,6 @@
 Ported to Python 3.
 """
 
-from future.utils import bchr
-
 import struct, time, os, sys
 
 from twisted.python import usage, failure
@@ -22,6 +20,9 @@ from allmydata.util import base32
 from allmydata.util.encodingutil import quote_output
 from allmydata.scripts.types_ import SubCommands
 
+def bchr(s):
+    return bytes([s])
+
 class DumpOptions(BaseOptions):
     def getSynopsis(self):
         return "Usage: tahoe [global-options] debug dump-share SHARE_FILENAME"

src/allmydata/test/mutable/util.py

@@ -2,7 +2,6 @@
 Ported to Python 3.
 """
 
-from future.utils import bchr
 
 from io import BytesIO
 import attr
@@ -20,6 +19,9 @@ from ..common import (
     EMPTY_CLIENT_CONFIG,
 )
 
+def bchr(s):
+    return bytes([s])
+
 def eventuaaaaaly(res=None):
     d = fireEventually(res)
     d.addCallback(fireEventually)

src/allmydata/test/test_download.py

@@ -2,8 +2,6 @@
 Ported to Python 3.
 """
 
-from future.utils import bchr
-
 # system-level upload+download roundtrip test, but using shares created from
 # a previous run. This asserts that the current code is capable of decoding
 # shares from a previous version.
@@ -29,6 +27,9 @@ from allmydata.immutable.downloader.fetcher import SegmentFetcher
 from allmydata.codec import CRSDecoder
 from foolscap.eventual import eventually, fireEventually, flushEventualQueue
 
+def bchr(s):
+    return bytes([s])
+
 plaintext = b"This is a moderate-sized file.\n" * 10
 mutable_plaintext = b"This is a moderate-sized mutable file.\n" * 10
 

src/allmydata/test/test_istorageserver.py

@@ -10,8 +10,6 @@ indexes.
 
 from __future__ import annotations
 
-from future.utils import bchr
-
 from random import Random
 from unittest import SkipTest
 
@@ -31,6 +29,8 @@ from allmydata.storage.server import StorageServer  # not a IStorageServer!!
 # are run in the same order.
 _RANDOM = Random(0)
 
+def bchr(s):
+    return bytes([s])
 
 def _randbytes(length):
     # type: (int) -> bytes

src/allmydata/test/test_storage.py

@@ -5,7 +5,6 @@ Ported to Python 3.
 """
 
 from __future__ import annotations
-from future.utils import bchr
 from six import ensure_str
 
 from io import (
@@ -20,6 +19,9 @@ import shutil
 from functools import partial
 from uuid import uuid4
 
+def bchr(s):
+    return bytes([s])
+
 from testtools.matchers import (
     Equals,
     NotEquals,