view tests/test-sparse-requirement.t @ 46089:8ff2d8359d0f

persistent-nodemap: properly ignore non-existent `.nd` data file

This code was meant to handle the case of a nodemap docket file
pointing to a nodemap data file that doesn’t exist (anymore),
but most likely caused an `UnboundLocalError` exception instead
when `data` was used on the next line without being defined.

This case is theoretically possible with a race condition
between two hg processes, but is hard to reproduce or test:

* Process A reads a docket file and finds a UID in it
  that points to a given data file name.
* Process B decides that this same data file needs compacting.
  It writes a new one with a different UID,
  overwrites the docket file,
  then removes the old data file.
* Only then process A tries to a open a file that doesn’t exist anymore.

Differential Revision: https://phab.mercurial-scm.org/D9533

  $ hg init repo
  $ cd repo

  $ touch a.html b.html c.py d.py

  $ cat > frontend.sparse << EOF
  > [include]
  > *.html
  > EOF

  $ hg -q commit -A -m initial

  $ echo 1 > a.html
  $ echo 1 > c.py
  $ hg commit -m 'commit 1'

Enable sparse profile

  $ cat .hg/requires
  dotencode
  fncache
  generaldelta
  revlogv1
  sparserevlog
  store
  testonly-simplestore (reposimplestore !)

  $ hg debugsparse --config extensions.sparse= --enable-profile frontend.sparse
  $ ls -A
  .hg
  a.html
  b.html

Requirement for sparse added when sparse is enabled

  $ cat .hg/requires
  dotencode
  exp-sparse
  fncache
  generaldelta
  revlogv1
  sparserevlog
  store
  testonly-simplestore (reposimplestore !)

Client without sparse enabled reacts properly

  $ hg files
  abort: repository is using sparse feature but sparse is not enabled; enable the "sparse" extensions to access
  [255]

Requirement for sparse is removed when sparse is disabled

  $ hg debugsparse --reset --config extensions.sparse=

  $ cat .hg/requires
  dotencode
  fncache
  generaldelta
  revlogv1
  sparserevlog
  store
  testonly-simplestore (reposimplestore !)

And client without sparse can access

  $ hg files
  a.html
  b.html
  c.py
  d.py
  frontend.sparse