view tests/test-obsmarkers-effectflag.t @ 39561:d06834e0f48e

wireprotov2peer: stream decoded responses

Previously, wire protocol version 2 would buffer all response data.
Only once all data was received did we CBOR decode it and resolve
the future associated with the command. This was obviously not
desirable. In future commits that introduce large response payloads,
this caused significant memory bloat and slowed down client
operations due to waiting on the server.

This commit refactors the response handling code so that response
data can be streamed.

Command response objects now contain a buffered CBOR decoder. As
new data arrives, it is fed into the decoder. Decoded objects are
made available to the generator as they are decoded.

Because there is a separate thread processing incoming frames and
feeding data into the response object, there is the potential for
race conditions when mutating response objects. So a lock has been
added to guard access to critical state variables.

Because the generator emitting decoded objects needs to wait on
those objects to become available, we've added an Event for the
generator to wait on so it doesn't busy loop. This does mean
there is the potential for deadlocks. And I'm pretty sure they can
occur in some scenarios. We already have a handful of TODOs around
this. But I've added some more. Fixing this will likely require
moving the background thread receiving frames into clienthandler.
We likely would have done this anyway when implementing the client
bits for the SSH transport.

Test output changes because the initial CBOR map holding the overall
response state is now always handled internally by the response
object.

Differential Revision: https://phab.mercurial-scm.org/D4474

Test the 'effect-flags' feature

Global setup
============

  $ . $TESTDIR/testlib/obsmarker-common.sh
  $ cat >> $HGRCPATH <<EOF
  > [ui]
  > interactive = true
  > [phases]
  > publish=False
  > [extensions]
  > rebase =
  > [experimental]
  > evolution = all
  > evolution.effect-flags = 1
  > EOF

  $ hg init $TESTTMP/effect-flags
  $ cd $TESTTMP/effect-flags
  $ mkcommit ROOT

amend touching the description only
-----------------------------------

  $ mkcommit A0
  $ hg commit --amend -m "A1"

check result

  $ hg debugobsolete --rev .
  471f378eab4c5e25f6c77f785b27c936efb22874 fdf9bde5129a28d4548fadd3f62b265cdd3b7a2e 0 (Thu Jan 01 00:00:00 1970 +0000) {'ef1': '1', 'operation': 'amend', 'user': 'test'}

amend touching the user only
----------------------------

  $ mkcommit B0
  $ hg commit --amend -u "bob <[e-mail]>"

check result

  $ hg debugobsolete --rev .
  ef4a313b1e0ade55718395d80e6b88c5ccd875eb 5485c92d34330dac9d7a63dc07e1e3373835b964 0 (Thu Jan 01 00:00:00 1970 +0000) {'ef1': '16', 'operation': 'amend', 'user': 'test'}

amend touching the date only
----------------------------

  $ mkcommit B1
  $ hg commit --amend -d "42 0"

check result

  $ hg debugobsolete --rev .
  2ef0680ff45038ac28c9f1ff3644341f54487280 4dd84345082e9e5291c2e6b3f335bbf8bf389378 0 (Thu Jan 01 00:00:00 1970 +0000) {'ef1': '32', 'operation': 'amend', 'user': 'test'}

amend touching the branch only
----------------------------

  $ mkcommit B2
  $ hg branch my-branch
  marked working directory as branch my-branch
  (branches are permanent and global, did you want a bookmark?)
  $ hg commit --amend

check result

  $ hg debugobsolete --rev .
  bd3db8264ceebf1966319f5df3be7aac6acd1a8e 14a01456e0574f0e0a0b15b2345486a6364a8d79 0 (Thu Jan 01 00:00:00 1970 +0000) {'ef1': '64', 'operation': 'amend', 'user': 'test'}

  $ hg up default
  0 files updated, 0 files merged, 1 files removed, 0 files unresolved

rebase (parents change)
-----------------------

  $ mkcommit C0
  $ mkcommit D0
  $ hg rebase -r . -d 'desc(B0)'
  rebasing 10:c85eff83a034 "D0" (tip)

check result

  $ hg debugobsolete --rev .
  c85eff83a0340efd9da52b806a94c350222f3371 da86aa2f19a30d6686b15cae15c7b6c908ec9699 0 (Thu Jan 01 00:00:00 1970 +0000) {'ef1': '4', 'operation': 'rebase', 'user': 'test'}

amend touching the diff
-----------------------

  $ mkcommit E0
  $ echo 42 >> E0
  $ hg commit --amend

check result

  $ hg debugobsolete --rev .
  ebfe0333e0d96f68a917afd97c0a0af87f1c3b5f 75781fdbdbf58a987516b00c980bccda1e9ae588 0 (Thu Jan 01 00:00:00 1970 +0000) {'ef1': '8', 'operation': 'amend', 'user': 'test'}

amend with multiple effect (desc and meta)
-------------------------------------------

  $ mkcommit F0
  $ hg branch my-other-branch
  marked working directory as branch my-other-branch
  $ hg commit --amend -m F1 -u "bob <[e-mail]>" -d "42 0"

check result

  $ hg debugobsolete --rev .
  fad47e5bd78e6aa4db1b5a0a1751bc12563655ff a94e0fd5f1c81d969381a76eb0d37ce499a44fae 0 (Thu Jan 01 00:00:00 1970 +0000) {'ef1': '113', 'operation': 'amend', 'user': 'test'}

rebase not touching the diff
----------------------------

  $ cat << EOF > H0
  > 0
  > 1
  > 2
  > 3
  > 4
  > 5
  > 6
  > 7
  > 8
  > 9
  > 10
  > EOF
  $ hg add H0
  $ hg commit -m 'H0'
  $ echo "H1" >> H0
  $ hg commit -m "H1"
  $ hg up -r "desc(H0)"
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
  $ cat << EOF > H0
  > H2
  > 0
  > 1
  > 2
  > 3
  > 4
  > 5
  > 6
  > 7
  > 8
  > 9
  > 10
  > EOF
  $ hg commit -m "H2"
  created new head
  $ hg rebase -s "desc(H1)" -d "desc(H2)" -t :merge3
  rebasing 17:b57fed8d8322 "H1"
  merging H0
  $ hg debugobsolete -r tip
  b57fed8d83228a8ae3748d8c3760a77638dd4f8c e509e2eb3df5d131ff7c02350bf2a9edd0c09478 0 (Thu Jan 01 00:00:00 1970 +0000) {'ef1': '4', 'operation': 'rebase', 'user': 'test'}

amend closing the branch should be detected as meta change
----------------------------------------------------------

  $ hg branch closedbranch
  marked working directory as branch closedbranch
  $ mkcommit G0
  $ mkcommit I0
  $ hg commit --amend --close-branch

check result

  $ hg debugobsolete -r .
  2f599e54c1c6974299065cdf54e1ad640bfb7b5d 12c6238b5e371eea00fd2013b12edce3f070928b 0 (Thu Jan 01 00:00:00 1970 +0000) {'ef1': '2', 'operation': 'amend', 'user': 'test'}