debugcommands: support connecting to HTTP peers
Now that we have the plumbing for logging socket activity, let's hook
it up to `hg debugwireproto` so we can collect low-level activity on
sockets.
The new code is a bit incomplete. But it is better than nothing:
`hg debugwireproto` is still heavily evolving.
The added test demonstrates some interesting behavior. For example,
we're calling socket.makefile() and doing I/O on that. TIL. We're also
sending an "Accept-Encoding: identity" request header.
Differential Revision: https://phab.mercurial-scm.org/D2726
$ hg init
$ $PYTHON -c 'open("a", "wb").write(b"confuse str.splitlines\nembedded\rnewline\n")'
$ hg ci -Ama -d '1 0'
adding a
$ echo clean diff >> a
$ hg ci -mb -d '2 0'
$ hg diff -r0 -r1
diff -r 107ba6f817b5 -r 310ce7989cdc a
--- a/a Thu Jan 01 00:00:01 1970 +0000
+++ b/a Thu Jan 01 00:00:02 1970 +0000
@@ -1,2 +1,3 @@
confuse str.splitlines
embedded\r (no-eol) (esc)
newline
+clean diff