tests/test-update-branches

prepush: add more precise error messages

Part of the patch is from [e-mail]

- indicate the branch name where there are multiple heads
- give better advice when hitting a possible race, where new heads are added
  between discovery and the call to branchmap(). In that case, asking the user
  to merge isn't helpful, since only remote has the changes.

#!/bin/sh

# Construct the following history tree:
#
# @  5:e1bb631146ca  b1
# |
# o  4:a4fdb3b883c4 0:b608b9236435  b1
# |
# | o  3:4b57d2520816 1:44592833ba9f
# | |
# | | o  2:063f31070f65
# | |/
# | o  1:44592833ba9f
# |/
# o  0:b608b9236435

hg init
echo foo > foo
echo zero > a
hg ci -qAm0
echo one > a ; hg ci -m1
echo two > a ; hg ci -m2
hg up -q 1
echo three > a ; hg ci -qm3
hg up -q 0
hg branch -q b1
echo four > a ; hg ci -qm4
echo five > a ; hg ci -qm5

echo % initial repo state
echo
hg --config 'extensions.graphlog=' \
    glog --template '{rev}:{node|short} {parents} {branches}\n'

# Test helper functions.

revtest () {
    msg=$1
    dirtyflag=$2   # 'clean' or 'dirty'
    startrev=$3
    targetrev=$4
    opt=$5
    echo % revtest $msg $startrev $targetrev
    hg up -qC $startrev
    test $dirtyflag = dirty && echo dirty > foo
    hg up $opt $targetrev
    hg parent --template 'parent={rev}\n'
    hg stat
}    

norevtest () {
    msg=$1
    dirtyflag=$2   # 'clean' or 'dirty'
    startrev=$3
    opt=$4
    echo % norevtest $msg $startrev
    hg up -qC $startrev
    test $dirtyflag = dirty && echo dirty > foo
    hg up $opt
    hg parent --template 'parent={rev}\n'
    hg stat
}    

# Test cases are documented in a table in the update function of merge.py.
# Cases are run as shown in that table, row by row.

norevtest 'none clean linear' clean 4
norevtest 'none clean same'   clean 2

revtest 'none clean linear' clean 1 2
revtest 'none clean same'   clean 2 3
revtest 'none clean cross'  clean 3 4

revtest 'none dirty linear' dirty 1 2
revtest 'none dirty same'   dirty 2 3
revtest 'none dirty cross'  dirty 3 4

revtest '-C dirty linear'   dirty 1 2 -C
revtest '-c dirty linear'   dirty 1 2 -c
norevtest '-c clean same'   clean 2 -c
revtest '-cC dirty linear'  dirty 1 2 -cC