tests/test-basic.t

parsers: make pack_dirstate take now in integer for consistency

On recent OS, 'stat.st_mtime' has a double precision floating point
value to represent nano seconds, but it is not wide enough for actual
file timestamp: nowadays, only 52 - 32 = 20 bit width is available for
decimal places in sec.

Therefore, casting it to 'int' may cause unexpected result. See also
changeset 13272104bb07 fixing issue4836 for detail.

For example, changed file A may be treated as "clean" unexpectedly in
steps below. "rounded now" is the value gotten by rounding via
'int(st.st_mtime)' or so.

    ---------------------+--------------------+------------------------
    "now"                |                    | timestamp of A (time_t)
    float  rounded time_t| action             | FS       dirstate
    ------ ------- ------+--------------------+-------- ---------------
    N+.nnn   N       N   |                    | ---      ---
                         | update file A      |  N
                         | dirstate.normal(A) |           N
    N+.999   N+1     N   |                    |
                         | dirstate.write()   |           N (*1)
                         |    :               |
                         | change file A      |  N
                         |    :               |
    N+1.00   N+1    N+1  |                    |
                         | "hg status" (*2)   |  N        N
    ------ ------- ------+--------------------+-------- ---------------

Timestamp N of A in dirstate isn't dropped at (*1), because "rounded
now" is N+1 at that time, even if 'st_mtime' in 'time_t' is still N.

Then, file A is unexpectedly treated as "clean" at (*2) in this case.

For consistent handling of 'stat.st_mtime', this patch makes
'pack_dirstate()' take 'now' argument not in floating point but in
integer.

This patch makes 'PyArg_ParseTuple()' in 'pack_dirstate()' use format
'i' (= checking type mismatch or overflow), even though it is ensured
that 'now' is in the range of 32bit signed integer by masking with
'_rangemask' (= 0x7fffffff) on caller side.

It should be cheaper enough than packing itself, and useful to
detect that legacy code invokes 'pack_dirstate()' with 'now' in
floating point value.

Create a repository:

  $ hg config
  defaults.backout=-d "0 0"
  defaults.commit=-d "0 0"
  defaults.shelve=--date "0 0"
  defaults.tag=-d "0 0"
  devel.all-warnings=true
  largefiles.usercache=$TESTTMP/.cache/largefiles (glob)
  ui.slash=True
  ui.interactive=False
  ui.mergemarkers=detailed
  ui.promptecho=True
  $ hg init t
  $ cd t

Make a changeset:

  $ echo a > a
  $ hg add a
  $ hg commit -m test

This command is ancient:

  $ hg history
  changeset:   0:acb14030fe0a
  tag:         tip
  user:        test
  date:        Thu Jan 01 00:00:00 1970 +0000
  summary:     test
  

Verify that updating to revision 0 via commands.update() works properly

  $ cat <<EOF > update_to_rev0.py
  > from mercurial import ui, hg, commands
  > myui = ui.ui()
  > repo = hg.repository(myui, path='.')
  > commands.update(myui, repo, rev=0)
  > EOF
  $ hg up null
  0 files updated, 0 files merged, 1 files removed, 0 files unresolved
  $ python ./update_to_rev0.py
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
  $ hg identify -n
  0


Poke around at hashes:

  $ hg manifest --debug
  b789fdd96dc2f3bd229c1dd8eedf0fc60e2b68e3 644   a

  $ hg cat a
  a

Verify should succeed:

  $ hg verify
  checking changesets
  checking manifests
  crosschecking files in changesets and manifests
  checking files
  1 files, 1 changesets, 1 total revisions

At the end...

  $ cd ..