view tests/test-update-dest.t @ 44248:12491abf93bd stable

worker: manually buffer reads from pickle stream

My previous fix (D8051, cb52e619c99e, which added Python's built-in buffering
to the pickle stream) has the problem that the selector will ignore the buffer.
When multiple pickled objects are read from the pipe into the buffer at once,
only one object will be loaded.

This can repeat until the buffer is full and delays the processing of completed
items until the worker exits, at which point the pipe is always considered
readable and all remaining items are processed.

This changeset reverts D8051, removing the buffer again. Instead, on Python 3
only, we use a wrapper to modify the "read" provided to the Unpickler to behave
more like a buffered read. We never read more bytes from the pipe than the
Unpickler requests, so the selector behaves as expected.

Also add a test case for "pickle data was truncated" issue.

https://phab.mercurial-scm.org/D8051#119193

Differential Revision: https://phab.mercurial-scm.org/D8076

Test update.requiredest
  $ cd $TESTTMP
  $ cat >> $HGRCPATH <<EOF
  > [commands]
  > update.requiredest = True
  > EOF
  $ hg init repo
  $ cd repo
  $ echo a >> a
  $ hg commit -qAm aa
  $ hg up
  abort: you must specify a destination
  (for example: hg update ".::")
  [255]
  $ hg up .
  0 files updated, 0 files merged, 0 files removed, 0 files unresolved
  $ HGPLAIN=1 hg up
  0 files updated, 0 files merged, 0 files removed, 0 files unresolved
  $ hg --config commands.update.requiredest=False up
  0 files updated, 0 files merged, 0 files removed, 0 files unresolved

  $ cd ..

Check update.requiredest interaction with pull --update
  $ hg clone repo clone
  updating to branch default
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
  $ cd repo
  $ echo a >> a
  $ hg commit -qAm aa
  $ cd ../clone
  $ hg pull --update
  abort: update destination required by configuration
  (use hg pull followed by hg update DEST)
  [255]

  $ cd ..

update.requiredest should silent the "hg update" text after pull
  $ hg init repo1
  $ cd repo1
  $ hg pull ../repo
  pulling from ../repo
  requesting all changes
  adding changesets
  adding manifests
  adding file changes
  added 2 changesets with 2 changes to 1 files
  new changesets 8f0162e483d0:048c2cb95949