# 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

Initial repo state:

  $ hg --config 'extensions.graphlog=' \

  >    glog --template '{rev}:{node|short} {parents} {branches}\n'

  @  5:e1bb631146ca  b1

  |

  o  4:a4fdb3b883c4 0:b608b9236435  b1

  |

  | o  3:4b57d2520816 1:44592833ba9f

  | |

  | | o  2:063f31070f65

  | |/

  | o  1:44592833ba9f

  |/

  o  0:b608b9236435

Test helper functions:

  $ revtest () {

  >     msg=$1

  >     dirtyflag=$2   # 'clean' or 'dirty'

  >     startrev=$3

  >     targetrev=$4

  >     opt=$5

  >     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

  >     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

  1 files updated, 0 files merged, 0 files removed, 0 files unresolved

  parent=5

  $ norevtest 'none clean same'   clean 2

  abort: crosses branches (merge branches or update --check to force update)

  parent=2

  $ revtest 'none clean linear' clean 1 2

  1 files updated, 0 files merged, 0 files removed, 0 files unresolved

  parent=2

  $ revtest 'none clean same'   clean 2 3

  1 files updated, 0 files merged, 0 files removed, 0 files unresolved

  parent=3

  $ revtest 'none clean cross'  clean 3 4

  1 files updated, 0 files merged, 0 files removed, 0 files unresolved

  parent=4

  $ revtest 'none dirty linear' dirty 1 2

  1 files updated, 0 files merged, 0 files removed, 0 files unresolved

  parent=2

  M foo

  $ revtest 'none dirty same'   dirty 2 3

  abort: crosses branches (merge branches or use --clean to discard changes)

  parent=2

  M foo

  $ revtest 'none dirty cross'  dirty 3 4

  abort: crosses branches (merge branches or use --clean to discard changes)

  parent=3

  M foo

  $ revtest '-C dirty linear'   dirty 1 2 -C

  2 files updated, 0 files merged, 0 files removed, 0 files unresolved

  parent=2

  $ revtest '-c dirty linear'   dirty 1 2 -c

  abort: uncommitted local changes

  parent=1

  M foo

  $ norevtest '-c clean same'   clean 2 -c

  1 files updated, 0 files merged, 0 files removed, 0 files unresolved

  parent=3

  $ revtest '-cC dirty linear'  dirty 1 2 -cC

  abort: cannot specify both -c/--check and -C/--clean

  parent=1

  M foo