tests/test-context.py.out

stream-clone: avoid opening a revlog in case we do not need it

Opening an revlog has a cost, especially if it is inline as we have to scan the
file and construct an index.

To prevent the associated slowdown, we just do a minimal scan to check that an
inline file is still inline, and simply stream the file without creating a
revlog when we can.

This provides a big boost compared to the previous changeset, even if the full
generation is still penalized by the initial gathering of information.

All benchmarks are run on linux with Python 3.10.7.
# benchmark.name             = hg.exchange.stream.generate
# benchmark.variants.version = v2

### Compared to the previous changesets

We get a large win all across the board!

# mercurial-2018-08-01-zstd-sparse-revlog
before:  0.250694 seconds
after:   0.105986 seconds  (-57.72%)
# pypy-2018-08-01-zstd-sparse-revlog
before:  3.885657 seconds
after:   1.709748 seconds  (-56.00%)
# netbeans-2018-08-01-zstd-sparse-revlog
before: 16.679371 seconds
after:   7.687469 seconds  (-53.91%)
# mozilla-central-2018-08-01-zstd-sparse-revlog
before: 38.575482 seconds
after:  17.520316 seconds  (-54.58%)
# mozilla-try-2019-02-18-zstd-sparse-revlog
before: 81.160994 seconds
after:  37.073753 seconds  (-54.32%)



### Compared to 6.4.3

We are still significantly slower than 6.4.3, the extra time is usually twice
slower than the extra time we observe on the locked section, which is a quite
interesting information.

Except for mercurial-central that is much faster. That discrepancy is not really
explained yet.

# mercurial-2018-08-01-zstd-sparse-revlog
6.4.3:  0.072560 seconds
after:  0.105986 seconds  (+46.07%) (- 0.03 seconds)
# pypy-2018-08-01-zstd-sparse-revlog
6.4.3:  1.211193 seconds
after:  1.709748 seconds  (+41.16%) (-0.45 seconds)
# netbeans-2018-08-01-zstd-sparse-revlog
6.4.3:  4.932843 seconds
after:  7.687469 seconds  (+55.84%) (-2.75 seconds)
# mozilla-central-2018-08-01-zstd-sparse-revlog
6.4.3: 34.012226 seconds
after: 17.520316 seconds  (-48.49%) (-16.49 seconds)
# mozilla-try-2019-02-18-zstd-sparse-revlog
6.4.3: 23.850555 seconds
after: 37.073753 seconds  (+55.44%) (+13.22 seconds)

workingfilectx.date = (1000, 0)
ASCII   : Gr?ezi!
Latin-1 : Grüezi!
UTF-8   : Grüezi!
<status modified=['foo'], added=[], removed=[], deleted=[], unknown=[], ignored=[], clean=[]>
diff --git a/foo b/foo
--- a/foo
+++ b/foo
@@ -1,1 +1,2 @@
 foo
+bar
= checking context.status():
== checking workingctx.status:
wctx._status=<status modified=['bar-m'], added=['bar-a'], removed=['bar-r'], deleted=[], unknown=[], ignored=[], clean=[]>
=== with "pattern match":
<status modified=['bar-m'], added=[], removed=[], deleted=[], unknown=[], ignored=[], clean=[]>
wctx._status=<status modified=['bar-m'], added=['bar-a'], removed=['bar-r'], deleted=[], unknown=[], ignored=[], clean=[]>
<status modified=[], added=['bar-m'], removed=[], deleted=[], unknown=[], ignored=[], clean=[]>
wctx._status=<status modified=['bar-m'], added=['bar-a'], removed=['bar-r'], deleted=[], unknown=[], ignored=[], clean=[]>
=== with "always match" and "listclean=True":
<status modified=['bar-m'], added=['bar-a'], removed=['bar-r'], deleted=[], unknown=[], ignored=[], clean=['foo']>
wctx._status=<status modified=['bar-m'], added=['bar-a'], removed=['bar-r'], deleted=[], unknown=[], ignored=[], clean=[]>
<status modified=[], added=['bar-a', 'bar-m'], removed=[], deleted=[], unknown=[], ignored=[], clean=['foo']>
wctx._status=<status modified=['bar-m'], added=['bar-a'], removed=['bar-r'], deleted=[], unknown=[], ignored=[], clean=[]>
== checking workingcommitctx.status:
wcctx._status=<status modified=['bar-m'], added=['bar-a'], removed=[], deleted=[], unknown=[], ignored=[], clean=[]>
=== with "always match":
<status modified=['bar-m'], added=['bar-a'], removed=[], deleted=[], unknown=[], ignored=[], clean=[]>
wcctx._status=<status modified=['bar-m'], added=['bar-a'], removed=[], deleted=[], unknown=[], ignored=[], clean=[]>
<status modified=[], added=['bar-a', 'bar-m', 'bar-r'], removed=[], deleted=[], unknown=[], ignored=[], clean=[]>
wcctx._status=<status modified=['bar-m'], added=['bar-a'], removed=[], deleted=[], unknown=[], ignored=[], clean=[]>
=== with "always match" and "listclean=True":
<status modified=['bar-m'], added=['bar-a'], removed=[], deleted=[], unknown=[], ignored=[], clean=['bar-r', 'foo']>
wcctx._status=<status modified=['bar-m'], added=['bar-a'], removed=[], deleted=[], unknown=[], ignored=[], clean=[]>
<status modified=[], added=['bar-a', 'bar-m', 'bar-r'], removed=[], deleted=[], unknown=[], ignored=[], clean=['foo']>
wcctx._status=<status modified=['bar-m'], added=['bar-a'], removed=[], deleted=[], unknown=[], ignored=[], clean=[]>
=== with "pattern match":
<status modified=['bar-m'], added=[], removed=[], deleted=[], unknown=[], ignored=[], clean=[]>
wcctx._status=<status modified=['bar-m'], added=['bar-a'], removed=[], deleted=[], unknown=[], ignored=[], clean=[]>
<status modified=[], added=['bar-m'], removed=[], deleted=[], unknown=[], ignored=[], clean=[]>
wcctx._status=<status modified=['bar-m'], added=['bar-a'], removed=[], deleted=[], unknown=[], ignored=[], clean=[]>
=== with "pattern match" and "listclean=True":
<status modified=[], added=[], removed=[], deleted=[], unknown=[], ignored=[], clean=['bar-r', 'foo']>
wcctx._status=<status modified=['bar-m'], added=['bar-a'], removed=[], deleted=[], unknown=[], ignored=[], clean=[]>
<status modified=[], added=['bar-r'], removed=[], deleted=[], unknown=[], ignored=[], clean=['foo']>
wcctx._status=<status modified=['bar-m'], added=['bar-a'], removed=[], deleted=[], unknown=[], ignored=[], clean=[]>
== commit with manifestlog invalidated
commit 1: 2efe531a913fa648867ab8824360371679d05a65
commit 2: 2caca91f6362020334384ebe27bae67315298abf
commit 3: abd6b0f49f338be22b094ef2b7425e8048f8337b