view tests/test-narrow-widen.t @ 37631:2f626233859b

wireproto: implement batching on peer executor interface

This is a bit more complicated than non-batch requests because we
need to buffer sends until the last request arrives *and* we need
to support resolving futures as data arrives from the remote.

In a classical concurrent.futures executor model, the future
"starts" as soon as it is submitted. However, we have nothing to
start until the last command is submitted.

If we did nothing, calling result() would deadlock, since the future
hasn't "started." So in the case where we queue the command, we return
a special future type whose result() will trigger sendcommands().
This eliminates the deadlock potential. It also serves as a check
against callers who may be calling result() prematurely, as it will
prevent any subsequent callcommands() from working. This behavior
is slightly annoying and a bit restrictive. But it's the world
that half duplex connections forces on us.

In order to support streaming responses, we were previously using
a generator. But with a futures-based API, we're using futures
and not generators. So in order to get streaming, we need a
background thread to read data from the server.

The approach taken in this patch is to leverage the ThreadPoolExecutor
from concurrent.futures for managing a background thread. We create
an executor and future that resolves when all response data is
processed (or an error occurs). When exiting the context manager,
we wait on that background reading before returning.

I was hoping we could manually spin up a threading.Thread and this
would be simple. But I ran into a few deadlocks when implementing.
After looking at the source code to concurrent.futures, I figured
it would just be easier to use a ThreadPoolExecutor than implement
all the code needed to manually manage a thread.

To prove this works, a use of the batch API in discovery has been
updated.

Differential Revision: https://phab.mercurial-scm.org/D3269

#testcases flat tree
  $ . "$TESTDIR/narrow-library.sh"

#if tree
  $ cat << EOF >> $HGRCPATH
  > [experimental]
  > treemanifest = 1
  > EOF
#endif

  $ hg init master
  $ cd master
  $ cat >> .hg/hgrc <<EOF
  > [narrow]
  > serveellipses=True
  > EOF

  $ mkdir inside
  $ echo 'inside' > inside/f
  $ hg add inside/f
  $ hg commit -m 'add inside'

  $ mkdir widest
  $ echo 'widest' > widest/f
  $ hg add widest/f
  $ hg commit -m 'add widest'

  $ mkdir outside
  $ echo 'outside' > outside/f
  $ hg add outside/f
  $ hg commit -m 'add outside'

  $ cd ..

narrow clone the inside file

  $ hg clone --narrow ssh://user@dummy/master narrow --include inside
  requesting all changes
  adding changesets
  adding manifests
  adding file changes
  added 2 changesets with 1 changes to 1 files
  new changesets *:* (glob)
  updating to branch default
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
  $ cd narrow
  $ hg tracked
  I path:inside
  $ ls
  inside
  $ cat inside/f
  inside
  $ cd ..

add more upstream files which we will include in a wider narrow spec

  $ cd master

  $ mkdir wider
  $ echo 'wider' > wider/f
  $ hg add wider/f
  $ echo 'widest v2' > widest/f
  $ hg commit -m 'add wider, update widest'

  $ echo 'widest v3' > widest/f
  $ hg commit -m 'update widest v3'

  $ echo 'inside v2' > inside/f
  $ hg commit -m 'update inside'

  $ mkdir outside2
  $ echo 'outside2' > outside2/f
  $ hg add outside2/f
  $ hg commit -m 'add outside2'

  $ echo 'widest v4' > widest/f
  $ hg commit -m 'update widest v4'

  $ hg log -T "{if(ellipsis, '...')}{node|short}: {desc}\n"
  *: update widest v4 (glob)
  *: add outside2 (glob)
  *: update inside (glob)
  *: update widest v3 (glob)
  *: add wider, update widest (glob)
  *: add outside (glob)
  *: add widest (glob)
  *: add inside (glob)

  $ cd ..

Widen the narrow spec to see the wider file. This should not get the newly
added upstream revisions.

  $ cd narrow
  $ hg tracked --addinclude wider/f
  comparing with ssh://user@dummy/master
  searching for changes
  no changes found
  saved backup bundle to $TESTTMP/narrow/.hg/strip-backup/*-widen.hg (glob)
  adding changesets
  adding manifests
  adding file changes
  added 2 changesets with 1 changes to 1 files
  new changesets *:* (glob)
  $ hg tracked
  I path:inside
  I path:wider/f

Pull down the newly added upstream revision.

  $ hg pull
  pulling from ssh://user@dummy/master
  searching for changes
  adding changesets
  adding manifests
  adding file changes
  added 4 changesets with 2 changes to 2 files
  new changesets *:* (glob)
  (run 'hg update' to get a working copy)
  $ hg update -r 'desc("add wider")'
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
  $ cat wider/f
  wider

  $ hg update -r 'desc("update inside")'
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
  $ cat wider/f
  wider
  $ cat inside/f
  inside v2

  $ hg log -T "{if(ellipsis, '...')}{node|short}: {desc}\n"
  ...*: update widest v4 (glob)
  *: update inside (glob)
  ...*: update widest v3 (glob)
  *: add wider, update widest (glob)
  ...*: add outside (glob)
  *: add inside (glob)

Check that widening with a newline fails

  $ hg tracked --addinclude 'widest
  > '
  abort: newlines are not allowed in narrowspec paths
  [255]

widen the narrow spec to include the widest file

  $ hg tracked --addinclude widest
  comparing with ssh://user@dummy/master
  searching for changes
  no changes found
  saved backup bundle to $TESTTMP/narrow/.hg/strip-backup/*-widen.hg (glob)
  adding changesets
  adding manifests
  adding file changes
  added 8 changesets with 7 changes to 3 files
  new changesets *:* (glob)
  $ hg tracked
  I path:inside
  I path:wider/f
  I path:widest
  $ hg update 'desc("add widest")'
  2 files updated, 0 files merged, 1 files removed, 0 files unresolved
  $ cat widest/f
  widest
  $ hg update 'desc("add wider, update widest")'
  2 files updated, 0 files merged, 0 files removed, 0 files unresolved
  $ cat wider/f
  wider
  $ cat widest/f
  widest v2
  $ hg update 'desc("update widest v3")'
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
  $ cat widest/f
  widest v3
  $ hg update 'desc("update widest v4")'
  2 files updated, 0 files merged, 0 files removed, 0 files unresolved
  $ cat widest/f
  widest v4

  $ hg log -T "{if(ellipsis, '...')}{node|short}: {desc}\n"
  *: update widest v4 (glob)
  ...*: add outside2 (glob)
  *: update inside (glob)
  *: update widest v3 (glob)
  *: add wider, update widest (glob)
  ...*: add outside (glob)
  *: add widest (glob)
  *: add inside (glob)

separate suite of tests: files from 0-10 modified in changes 0-10. This allows
more obvious precise tests tickling particular corner cases.

  $ cd ..
  $ hg init upstream
  $ cd upstream
  $ cat >> .hg/hgrc <<EOF
  > [narrow]
  > serveellipses=True
  > EOF
  $ for x in `$TESTDIR/seq.py 0 10`
  > do
  >   mkdir d$x
  >   echo $x > d$x/f
  >   hg add d$x/f
  >   hg commit -m "add d$x/f"
  > done
  $ hg log -T "{node|short}: {desc}\n"
  *: add d10/f (glob)
  *: add d9/f (glob)
  *: add d8/f (glob)
  *: add d7/f (glob)
  *: add d6/f (glob)
  *: add d5/f (glob)
  *: add d4/f (glob)
  *: add d3/f (glob)
  *: add d2/f (glob)
  *: add d1/f (glob)
  *: add d0/f (glob)

make narrow clone with every third node.

  $ cd ..
  $ hg clone --narrow ssh://user@dummy/upstream narrow2 --include d0 --include d3 --include d6 --include d9
  requesting all changes
  adding changesets
  adding manifests
  adding file changes
  added 8 changesets with 4 changes to 4 files
  new changesets *:* (glob)
  updating to branch default
  4 files updated, 0 files merged, 0 files removed, 0 files unresolved
  $ cd narrow2
  $ hg tracked
  I path:d0
  I path:d3
  I path:d6
  I path:d9
  $ hg verify
  checking changesets
  checking manifests
  checking directory manifests (tree !)
  crosschecking files in changesets and manifests
  checking files
  4 files, 8 changesets, 4 total revisions
  $ hg log -T "{if(ellipsis, '...')}{node|short}: {desc}\n"
  ...*: add d10/f (glob)
  *: add d9/f (glob)
  ...*: add d8/f (glob)
  *: add d6/f (glob)
  ...*: add d5/f (glob)
  *: add d3/f (glob)
  ...*: add d2/f (glob)
  *: add d0/f (glob)
  $ hg tracked --addinclude d1
  comparing with ssh://user@dummy/upstream
  searching for changes
  no changes found
  saved backup bundle to $TESTTMP/narrow2/.hg/strip-backup/*-widen.hg (glob)
  adding changesets
  adding manifests
  adding file changes
  added 9 changesets with 5 changes to 5 files
  new changesets *:* (glob)
  $ hg tracked
  I path:d0
  I path:d1
  I path:d3
  I path:d6
  I path:d9
  $ hg log -T "{if(ellipsis, '...')}{node|short}: {desc}\n"
  ...*: add d10/f (glob)
  *: add d9/f (glob)
  ...*: add d8/f (glob)
  *: add d6/f (glob)
  ...*: add d5/f (glob)
  *: add d3/f (glob)
  ...*: add d2/f (glob)
  *: add d1/f (glob)
  *: add d0/f (glob)

Verify shouldn't claim the repo is corrupt after a widen.

  $ hg verify
  checking changesets
  checking manifests
  checking directory manifests (tree !)
  crosschecking files in changesets and manifests
  checking files
  5 files, 9 changesets, 5 total revisions

Widening preserves parent of local commit

  $ cd ..
  $ hg clone -q --narrow ssh://user@dummy/upstream narrow3 --include d2 -r 2
  $ cd narrow3
  $ hg log -T "{if(ellipsis, '...')}{node|short}: {desc}\n"
  *: add d2/f (glob)
  ...*: add d1/f (glob)
  $ hg pull -q -r 3
  $ hg co -q tip
  $ hg pull -q -r 4
  $ echo local > d2/f
  $ hg ci -m local
  created new head
  $ hg tracked -q --addinclude d0 --addinclude d9

Widening preserves bookmarks

  $ cd ..
  $ hg clone -q --narrow ssh://user@dummy/upstream narrow-bookmarks --include d4
  $ cd narrow-bookmarks
  $ echo local > d4/f
  $ hg ci -m local
  $ hg bookmarks bookmark
  $ hg bookmarks
   * bookmark                  3:* (glob)
  $ hg -q tracked --addinclude d2
  $ hg bookmarks
   * bookmark                  5:* (glob)
  $ hg log -r bookmark -T '{desc}\n'
  local

Widening that fails can be recovered from

  $ cd ..
  $ hg clone -q --narrow ssh://user@dummy/upstream interrupted --include d0
  $ cd interrupted
  $ echo local > d0/f
  $ hg ci -m local
  $ hg log -T "{if(ellipsis, '...')}{rev}: {desc}\n"
  2: local
  ...1: add d10/f
  0: add d0/f
  $ hg bookmarks bookmark
  $ hg --config hooks.pretxnchangegroup.bad=false tracked --addinclude d1
  comparing with ssh://user@dummy/upstream
  searching for changes
  no changes found
  saved backup bundle to $TESTTMP/interrupted/.hg/strip-backup/*-widen.hg (glob)
  adding changesets
  adding manifests
  adding file changes
  added 3 changesets with 2 changes to 2 files
  transaction abort!
  rollback completed
  abort: pretxnchangegroup.bad hook exited with status 1
  [255]
  $ hg log -T "{if(ellipsis, '...')}{rev}: {desc}\n"
  $ hg bookmarks
  no bookmarks set
  $ hg unbundle .hg/strip-backup/*-widen.hg
  adding changesets
  adding manifests
  adding file changes
  added 3 changesets with 2 changes to 1 files
  new changesets *:* (glob)
  (run 'hg update' to get a working copy)
  $ hg log -T "{if(ellipsis, '...')}{rev}: {desc}\n"
  2: local
  ...1: add d10/f
  0: add d0/f
  $ hg bookmarks
   * bookmark                  2:* (glob)