histedit: break _histedit function into smaller pieces
We add _getgoal, _validateargs.
This is a part of bigger effort to refactor histedit. Initial steps are to
break _histedit function into smaller pieces which will supposedly be more
understandable. After this is done, I will have a better understanding
of how histedit works and apply that to fix issue4800.
#require test-repo execbit
$ cd "`dirname "$TESTDIR"`"
look for python scripts without the execute bit
$ hg files 'set:**.py and not exec() and grep(r"^#!.*?python")'
[1]
look for python scripts with execute bit but not shebang
$ hg files 'set:**.py and exec() and not grep(r"^#!.*?python")'
[1]
look for shell scripts with execute bit but not shebang
$ hg files 'set:**.sh and exec() and not grep(r"^#!.*(ba)?sh")'
[1]
look for non scripts with no shebang
$ hg files 'set:exec() and not **.sh and not **.py and not grep(r"^#!")'
[1]