tests/test-contrib-perf.t

upgrade: move descriptions and selection logic in individual classes

Our goal here is to get top level definition for all the format variants. Having
them defined outside of the function enabled other users of that logic.

They are two keys components of a format variant:

1) the name and various descriptions of its effect,

2) the code that checks if the repo is using this variant and if the config
   enables it.

That second items make us pick a class-based approach, since different variants
requires different code (even if in practice, many can reuse the same logic).
Each variants define its own class that is then used like a singleton.  The
class-based approach also clarify the definitions part a bit since each are
simple assignment in an indented block.

The 'fromdefault' and 'fromconfig' are respectively replaced by a class
attribute and a method to be called at the one place where "fromconfig"
matters.

Overall, they are many viable approach for this, but this is the one I picked.

#require test-repo

Set vars:

  $ . "$TESTDIR/helpers-testrepo.sh"
  $ CONTRIBDIR="$TESTDIR/../contrib"

Prepare repo:

  $ hg init

  $ echo this is file a > a
  $ hg add a
  $ hg commit -m first

  $ echo adding to file a >> a
  $ hg commit -m second

  $ echo adding more to file a >> a
  $ hg commit -m third

  $ hg up -r 0
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
  $ echo merge-this >> a
  $ hg commit -m merge-able
  created new head

  $ hg up -r 2
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved

perfstatus

  $ cat >> $HGRCPATH << EOF
  > [extensions]
  > perfstatusext=$CONTRIBDIR/perf.py
  > [perf]
  > presleep=0
  > stub=on
  > parentscount=1
  > EOF
  $ hg help perfstatusext
  perfstatusext extension - helper extension to measure performance
  
  list of commands:
  
   perfaddremove
                 (no help text available)
   perfancestors
                 (no help text available)
   perfancestorset
                 (no help text available)
   perfannotate  (no help text available)
   perfbdiff     benchmark a bdiff between revisions
   perfbranchmap
                 benchmark the update of a branchmap
   perfcca       (no help text available)
   perfchangegroupchangelog
                 Benchmark producing a changelog group for a changegroup.
   perfchangeset
                 (no help text available)
   perfctxfiles  (no help text available)
   perfdiffwd    Profile diff of working directory changes
   perfdirfoldmap
                 (no help text available)
   perfdirs      (no help text available)
   perfdirstate  (no help text available)
   perfdirstatedirs
                 (no help text available)
   perfdirstatefoldmap
                 (no help text available)
   perfdirstatewrite
                 (no help text available)
   perffncacheencode
                 (no help text available)
   perffncacheload
                 (no help text available)
   perffncachewrite
                 (no help text available)
   perfheads     (no help text available)
   perfindex     (no help text available)
   perfloadmarkers
                 benchmark the time to parse the on-disk markers for a repo
   perflog       (no help text available)
   perflookup    (no help text available)
   perflrucachedict
                 (no help text available)
   perfmanifest  (no help text available)
   perfmergecalculate
                 (no help text available)
   perfmoonwalk  benchmark walking the changelog backwards
   perfnodelookup
                 (no help text available)
   perfparents   (no help text available)
   perfpathcopies
                 (no help text available)
   perfrawfiles  (no help text available)
   perfrevlog    Benchmark reading a series of revisions from a revlog.
   perfrevlogchunks
                 Benchmark operations on revlog chunks.
   perfrevlogrevision
                 Benchmark obtaining a revlog revision.
   perfrevrange  (no help text available)
   perfrevset    benchmark the execution time of a revset
   perfstartup   (no help text available)
   perfstatus    (no help text available)
   perftags      (no help text available)
   perftemplating
                 (no help text available)
   perfvolatilesets
                 benchmark the computation of various volatile set
   perfwalk      (no help text available)
   perfwrite     microbenchmark ui.write
  
  (use 'hg help -v perfstatusext' to show built-in aliases and global options)
  $ hg perfaddremove
  $ hg perfancestors
  $ hg perfancestorset 2
  $ hg perfannotate a
  $ hg perfbdiff -c 1
  $ hg perfbdiff --alldata 1
  $ hg perfbranchmap
  $ hg perfcca
  $ hg perfchangegroupchangelog
  $ hg perfchangeset 2
  $ hg perfctxfiles 2
  $ hg perfdiffwd
  $ hg perfdirfoldmap
  $ hg perfdirs
  $ hg perfdirstate
  $ hg perfdirstatedirs
  $ hg perfdirstatefoldmap
  $ hg perfdirstatewrite
  $ hg perffncacheencode
  $ hg perffncacheload
  $ hg perffncachewrite
  $ hg perfheads
  $ hg perfindex
  $ hg perfloadmarkers
  $ hg perflog
  $ hg perflookup 2
  $ hg perflrucache
  $ hg perfmanifest 2
  $ hg perfmergecalculate -r 3
  $ hg perfmoonwalk
  $ hg perfnodelookup 2
  $ hg perfpathcopies 1 2
  $ hg perfrawfiles 2
  $ hg perfrevlog .hg/store/data/a.i
  $ hg perfrevlogrevision -m 0
  $ hg perfrevlogchunks -c
  $ hg perfrevrange
  $ hg perfrevset 'all()'
  $ hg perfstartup
  $ hg perfstatus
  $ hg perftags
  $ hg perftemplating
  $ hg perfvolatilesets
  $ hg perfwalk
  $ hg perfparents

Check perf.py for historical portability

  $ cd "$TESTDIR/.."

  $ (hg files -r 1.2 glob:mercurial/*.c glob:mercurial/*.py;
  >  hg files -r tip glob:mercurial/*.c glob:mercurial/*.py) |
  > "$TESTDIR"/check-perf-code.py contrib/perf.py
  contrib/perf.py:869:
   >             r.revision(r.node(x))
   don't convert rev to node before passing to revision(nodeorrev)
  [1]