tests/testlib/exchange-obsmarker-util.sh

revset: optimize "draft() & ::x" pattern

The `draft() & ::x` type query could be common for selecting one or more
draft feature branches being worked on.

Before this patch, `::x` may travel through the changelog DAG for a long
distance until it gets a smaller revision number than `min(draft())`. It
could be very slow on long changelog with distant (in terms of revision
numbers) drafts.

This patch adds a fast path for this situation, and will stop traveling the
changelog DAG once `::x` hits a non-draft revision.

The fast path also works for `secret()` and `not public()`.

To measure the performance difference, I used drawdag to create a repo that
emulates distant drafts:

          DRAFT4
           |
          DRAFT3 # draft
          /
  PUBLIC9999 # public
      |
  PUBLIC9998
      |
      .   DRAFT2
      .    |
      .   DRAFT1 # draft
      |   /
  PUBLIC0001 # public

And measured the performance using the repo:

  (BEFORE)
  $ hg perfrevset 'draft() & ::(DRAFT2+DRAFT4)'
  ! wall 0.017132 comb 0.010000 user 0.010000 sys 0.000000 (best of 156)
  $ hg perfrevset 'draft() & ::(all())'
  ! wall 0.024221 comb 0.030000 user 0.030000 sys 0.000000 (best of 113)
  (AFTER)
  $ hg perfrevset 'draft() & ::(DRAFT2+DRAFT4)'
  ! wall 0.000243 comb 0.000000 user 0.000000 sys 0.000000 (best of 9303)
  $ hg perfrevset 'draft() & ::(all())'
  ! wall 0.004319 comb 0.000000 user 0.000000 sys 0.000000 (best of 655)

Differential Revision: https://phab.mercurial-scm.org/D441

#!/bin/sh
# setup config and various utility to test obsolescence marker exchanges tests

cat >> $TESTTMP/prune.sh << EOF
rev=\`hg log --hidden --template '{node}\n' --rev "\$3"\`

hg debugobsolete --record-parents \$1 "\$2" \$rev \
   && hg up --quiet 'max((::.) - obsolete())'
EOF

cat >> $HGRCPATH <<EOF
[web]
# We test http pull and push, drop authentication requirement
push_ssl = false
allow_push = *

[ui]
# simpler log output
logtemplate ="{node|short} ({phase}): {desc}\n"

[phases]
# non publishing server
publish=False

[experimental]
# reduce output changes
bundle2-output-capture=True
# enable evolution
evolution=all

[extensions]
# we need to strip some changeset for some test cases
hgext.strip=

[devel]
strip-obsmarkers = no

[alias]
# fix date used to create obsolete markers.
debugobsolete=debugobsolete -d '0 0'
# poor man substiture to the evolve 'hg prune'. using prune makes the test clearer and 
prune = !sh $TESTTMP/prune.sh \$1 "\$2" "\$3"
EOF

mkcommit() {
   echo "$1" > "$1"
   hg add "$1"
   hg ci -m "$1"
}
getid() {
   hg log --hidden --template '{node}\n' --rev "$1"
}

setuprepos() {
    echo creating test repo for test case $1
    mkdir $1
    cd $1
    echo - pulldest
    hg init pushdest
    cd pushdest
    mkcommit O
    hg phase --public .
    cd ..
    echo - main
    hg clone -q pushdest main
    echo - pushdest
    hg clone -q main pulldest
    echo 'cd into `main` and proceed with env setup'
}

inspect_obsmarkers (){
    # This exist as its own function to help the evolve extension reuse the tests as is.
    # The evolve extensions version will includes more advances query (eg:
    # related to obsmarkers discovery) to this.
    echo 'obsstore content'
    echo '================'
    hg debugobsolete
}

dotest() {
    # dotest TESTNAME [TARGETNODE] [PUSHFLAGS+]
    #
    # test exchange for the given test case.
    #
    # This function performs push and pull in all directions through all
    # protocols and display the resulting obsolescence markers on all sides.

    testcase=$1
    shift
    target="$1"
    if [ $# -gt 0 ]; then
        shift
    fi
    targetnode=""
    desccall=""
    cd $testcase
    echo "## Running testcase $testcase"
    if [ -n "$target" ]; then
        desccall="desc("\'"$target"\'")"
        targetnode="`hg -R main id -qr \"$desccall\"`"
        echo "# testing echange of \"$target\" ($targetnode)"
    fi
    echo "## initial state"
    echo "# obstore: main"
    hg -R main     debugobsolete | sort
    echo "# obstore: pushdest"
    hg -R pushdest debugobsolete | sort
    echo "# obstore: pulldest"
    hg -R pulldest debugobsolete | sort

    if [ -n "$target" ]; then
        echo "## pushing \"$target\"" from main to pushdest
        hg -R main push -r "$desccall" $@ pushdest
    else
        echo "## pushing from main to pushdest"
        hg -R main push pushdest $@
    fi
    echo "## post push state"
    echo "# obstore: main"
    hg -R main     debugobsolete | sort
    echo "# obstore: pushdest"
    hg -R pushdest debugobsolete | sort
    echo "# obstore: pulldest"
    hg -R pulldest debugobsolete | sort
    if [ -n "$target" ]; then
        echo "## pulling \"$targetnode\"" from main into pulldest
        hg -R pulldest pull -r $targetnode $@ main
    else
        echo "## pulling from main into pulldest"
        hg -R pulldest pull main $@
    fi
    echo "## post pull state"
    echo "# obstore: main"
    hg -R main     debugobsolete | sort
    echo "# obstore: pushdest"
    hg -R pushdest debugobsolete | sort
    echo "# obstore: pulldest"
    hg -R pulldest debugobsolete | sort

    cd ..

}