( )⚙ D2467 sshpeer: support not reading and forwarding stderr

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Differential D2467

sshpeer: support not reading and forwarding stderr
ClosedPublic

Authored by indygreg on Feb 26 2018, 4:16 PM.

Details

Reviewers
durin42
Group Reviewers
hg-reviewers
Commits
rHG1a36ef7df70a: sshpeer: support not reading and forwarding stderr
rHG9dfedb47d000: sshpeer: support not reading and forwarding stderr
Summary

The "doublepipe" primitive as used by sshpeer will automatically read
from stderr and forward output to the local ui.

This poses problems for deterministic testing because reads may not
be consistent. For example, the server may not be done sending all
output to stderr and the client will perform different numbers of
read operations or will read from stderr and stdout at different times.

To make tests deterministic, we'll need to disable the "doublepipe"
primitive and perform stderr I/O explicitly. We add an argument to the
sshpeer constructor to disable the use of the doublepipe.

Diff Detail

Repository
rHG Mercurial
Lint
Lint Skipped
Unit
Unit Tests Skipped

Event Timeline

indygreg created this revision.Feb 26 2018, 4:16 PM
indygreg updated this revision to Diff 6255.Mar 1 2018, 11:30 AM
durin42 accepted this revision.Mar 1 2018, 4:39 PM
This revision is now accepted and ready to land.Mar 1 2018, 4:39 PM
Closed by commit rHG9dfedb47d000: sshpeer: support not reading and forwarding stderr (authored by indygreg). · Explain WhyMar 1 2018, 4:55 PM
This revision was automatically updated to reflect the committed changes.

Revision Contents
Changeset List

PathPackages
Mmercurial/sshpeer.py (10 lines)

Diff 6145

mercurial/sshpeer.py

badresponse() badresponse()
# Flush any output on stderr before proceeding. # Flush any output on stderr before proceeding.
_forwardoutput(ui, stderr) _forwardoutput(ui, stderr)
return protoname, caps return protoname, caps
class sshv1peer(wireproto.wirepeer): class sshv1peer(wireproto.wirepeer):
def __init__(self, ui, url, proc, stdin, stdout, stderr, caps): def __init__(self, ui, url, proc, stdin, stdout, stderr, caps,
autoreadstderr=True):
"""Create a peer from an existing SSH connection. """Create a peer from an existing SSH connection.
``proc`` is a handle on the underlying SSH process. ``proc`` is a handle on the underlying SSH process.
``stdin``, ``stdout``, and ``stderr`` are handles on the stdio ``stdin``, ``stdout``, and ``stderr`` are handles on the stdio
pipes for that process. pipes for that process.
``caps`` is a set of capabilities supported by the remote. ``caps`` is a set of capabilities supported by the remote.
``autoreadstderr`` denotes whether to automatically read from
stderr and to forward its output.
""" """
self._url = url self._url = url
self._ui = ui self._ui = ui
# self._subprocess is unused. Keeping a handle on the process # self._subprocess is unused. Keeping a handle on the process
# holds a reference and prevents it from being garbage collected. # holds a reference and prevents it from being garbage collected.
self._subprocess = proc self._subprocess = proc
# And we hook up our "doublepipe" wrapper to allow querying # And we hook up our "doublepipe" wrapper to allow querying
# stderr any time we perform I/O. # stderr any time we perform I/O.
if autoreadstderr:
stdout = doublepipe(ui, util.bufferedinputpipe(stdout), stderr) stdout = doublepipe(ui, util.bufferedinputpipe(stdout), stderr)
stdin = doublepipe(ui, stdin, stderr) stdin = doublepipe(ui, stdin, stderr)
self._pipeo = stdin self._pipeo = stdin
self._pipei = stdout self._pipei = stdout
self._pipee = stderr self._pipee = stderr
self._caps = caps self._caps = caps
# Commands that have a "framed" response where the first line of the # Commands that have a "framed" response where the first line of the
# response contains the length of that response. # response contains the length of that response.