view tests/test-status-tracked-key.t @ 48684:568f63b5a30f

dirstate: introduce a "tracked-key" feature

A new format variant is introduced. When used, a `tracked-key` file will be
generated. That file will be update when the set of tracked file might have
changed. This will be useful for external automation (e.g. build tool) to be
notified when the set of relevant files changes.

One of the motivation for this changes is to mitigate effect dirstate-v2 has on
such automation. Since the dirstate file is updated much more frequently on
dirstate-v2, monitoring update to that file is no longer a viable strategy.

See the associated documentation for details about the feature

To prevent older client to update the repository without updating that file, a
new requirements is introduced.

The `postfinalizegenerators` business is a bit weird, so I'll likely clean that
up soon.

Differential Revision: https://phab.mercurial-scm.org/D12124

==============================
Test the "tracked key" feature
==============================

The tracked key feature provide a file that get updated when the set of tracked
files get updated.

basic setup

  $ cat << EOF >> $HGRCPATH
  > [format]
  > exp-dirstate-tracked-key-version=1
  > EOF

  $ hg init tracked-key-test
  $ cd tracked-key-test
  $ hg debugbuilddag '.+10' -n
  $ hg log -G -T '{rev} {desc} {files}\n'
  o  10 r10 nf10
  |
  o  9 r9 nf9
  |
  o  8 r8 nf8
  |
  o  7 r7 nf7
  |
  o  6 r6 nf6
  |
  o  5 r5 nf5
  |
  o  4 r4 nf4
  |
  o  3 r3 nf3
  |
  o  2 r2 nf2
  |
  o  1 r1 nf1
  |
  o  0 r0 nf0
  
  $ hg up tip
  11 files updated, 0 files merged, 0 files removed, 0 files unresolved
  $ hg files
  nf0
  nf1
  nf10
  nf2
  nf3
  nf4
  nf5
  nf6
  nf7
  nf8
  nf9

key-file exists
-----------

The tracked key file should exist

  $ ls -1 .hg/dirstate*
  .hg/dirstate
  .hg/dirstate-tracked-key

key-file stay the same if the tracked set is unchanged
------------------------------------------------------

(copy its content for later comparison)

  $ cp .hg/dirstate-tracked-key ../key-bck
  $ echo foo >> nf0
  $ sleep 1
  $ hg status
  M nf0
  $ diff --brief .hg/dirstate-tracked-key ../key-bck
  $ hg revert -C nf0
  $ sleep 1
  $ hg status
  $ diff --brief .hg/dirstate-tracked-key ../key-bck

key-file change if the tracked set is changed manually
------------------------------------------------------

adding a file to tracking

  $ cp .hg/dirstate-tracked-key ../key-bck
  $ echo x > x
  $ hg add x
  $ diff --brief .hg/dirstate-tracked-key ../key-bck
  Files .hg/dirstate-tracked-key and ../key-bck differ
  [1]

remove a file from tracking
(forget)

  $ cp .hg/dirstate-tracked-key ../key-bck
  $ hg forget x
  $ diff --brief .hg/dirstate-tracked-key ../key-bck
  Files .hg/dirstate-tracked-key and ../key-bck differ
  [1]

(remove)

  $ cp .hg/dirstate-tracked-key ../key-bck
  $ hg remove nf1
  $ diff --brief .hg/dirstate-tracked-key ../key-bck
  Files .hg/dirstate-tracked-key and ../key-bck differ
  [1]

key-file changes on revert (when applicable)
--------------------------------------------

  $ cp .hg/dirstate-tracked-key ../key-bck
  $ hg status
  R nf1
  ? x
  $ hg revert --all
  undeleting nf1
  $ hg status
  ? x
  $ diff --brief .hg/dirstate-tracked-key ../key-bck
  Files .hg/dirstate-tracked-key and ../key-bck differ
  [1]


`hg update` does affect the key-file (when needed)
--------------------------------------------------

update changing the tracked set

(removing)

  $ cp .hg/dirstate-tracked-key ../key-bck
  $ hg status --rev . --rev '.#generations[-1]'
  R nf10
  $ hg up '.#generations[-1]'
  0 files updated, 0 files merged, 1 files removed, 0 files unresolved
  $ diff --brief .hg/dirstate-tracked-key ../key-bck
  Files .hg/dirstate-tracked-key and ../key-bck differ
  [1]

(adding)

  $ cp .hg/dirstate-tracked-key ../key-bck
  $ hg status --rev . --rev '.#generations[1]'
  A nf10
  $ hg up '.#generations[1]'
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
  $ diff --brief .hg/dirstate-tracked-key ../key-bck
  Files .hg/dirstate-tracked-key and ../key-bck differ
  [1]

update not affecting the tracked set

  $ echo foo >> nf0
  $ hg commit -m foo

  $ cp .hg/dirstate-tracked-key ../key-bck
  $ hg status --rev . --rev '.#generations[-1]'
  M nf0
  $ hg up '.#generations[-1]'
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
  $ diff --brief .hg/dirstate-tracked-key ../key-bck