# HG changeset patch
# User Augie Fackler <augie@google.com>
# Date 2020-09-01 13:46:15
# Node ID e666f601b3eaadc3583ef3575aaa84786bc1b65b
# Parent  c25efc468a4939682031d2a16a3c897cf59f0fb9
# Parent  42202492a3b9aed0b2810560dfae1feb56a8bea4

merge with stable

diff --git a/.hgsigs b/.hgsigs
--- a/.hgsigs
+++ b/.hgsigs
@@ -200,3 +200,4 @@ 065704cbdbdbb05dcd6bb814eb9bbdd982211b28
 0ea9c86fac8974cd74dc12ea681c8986eb6da6c4 0 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
 28163c5de797e5416f9b588940f4608269b4d50a 0 iQJJBAABCgAzFiEE64UTlbQiPuL3ugso2lR0C/CHMroFAl8VylYVHDc4OTVwdWxraXRAZ21haWwuY29tAAoJENpUdAvwhzK6zUEQAJoLrpMmHvM4VYepsu2UTFI2VA1iL7cd+AOlcAokn/29JOqmAWD2ujUMv2FIdcNqAW/ayeEW9oLAi0dOfLqS6UAxfw8hYEiM6hV1R0W9DOUV5CRQ5T86cbaZFBrrJL9N87tHjro0eS3i8iwPpklnWrwf8fkcBq8SKFBZbubat8X/mejbbq6zYML9SEhtrKHyBPL5iQjzqDEGWyTqJYusHGVkAtFMZWxStDA3VSr3x9Iy0495XdegYRkUFytRsz1zB3vfawJsWRY7tQfff5CF6knZ+UIpetjgJIlm21/vQmcL1aTIxem0CFQt5bub1a+LYI1TWt59rFrnRj97K6Kq6xG6lPjnM3l/w2nehGfpL/Tfjih9gY8ToS1GRg2JJ4IiXAI57fv5fZcZv3R0xAGfWfRdwMsO2siaDrd4R/kraDlTPZZ1Qmpa+Y4XtFxSGIXtf9DWt/7pw81GWrUH0u/WYjfSpYvbdr7GvYpdzxMmtEULoxJ9ibyFDyDyqEkJfT6onFb1aaHQJ1mjho1x93uDeAEq0R5UCSNDxi31Hq/nWtA9IwCjYeQkv9D1rxFcSx3MetUpJofdBYvvFsvjNTM5GO2ETvsjyzXf2Qa3oobQoKBqbTuKR6yJlCsmWJuejbDbblBdx3mj4xpXxmX/YQHQ+2PYrfopel/8Am8j7sq0sNcV
 7fc3c5fbc65f6fe85d70ea63923b8767dda4f2e0 0 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
+f62bb5d07848ca598aa860a517394130b61bf2ee 0 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
diff --git a/.hgtags b/.hgtags
--- a/.hgtags
+++ b/.hgtags
@@ -213,3 +213,4 @@ 065704cbdbdbb05dcd6bb814eb9bbdd982211b28
 0ea9c86fac8974cd74dc12ea681c8986eb6da6c4 5.4.2
 28163c5de797e5416f9b588940f4608269b4d50a 5.5rc0
 7fc3c5fbc65f6fe85d70ea63923b8767dda4f2e0 5.5
+f62bb5d07848ca598aa860a517394130b61bf2ee 5.5.1
diff --git a/mercurial/keepalive.py b/mercurial/keepalive.py
--- a/mercurial/keepalive.py
+++ b/mercurial/keepalive.py
@@ -542,7 +542,11 @@ class HTTPResponse(httplib.HTTPResponse)
             return line
 
         # No newline in local buffer. Read until we find one.
-        chunks = [self._rbuf]
+        # readinto read via readinto will already return _rbuf
+        if self._raw_readinto is None:
+            chunks = [self._rbuf]
+        else:
+            chunks = []
         i = -1
         readsize = self._rbufsize
         while True:
diff --git a/tests/test-check-format.t b/tests/test-check-format.t
--- a/tests/test-check-format.t
+++ b/tests/test-check-format.t
@@ -1,4 +1,4 @@
-#require black
+#require black test-repo
 
   $ cd $RUNTESTDIR/..
   $ black --config=black.toml --check --diff `hg files 'set:(**.py + grep("^#!.*python")) - mercurial/thirdparty/**'`