contrib/win32/hg.bat

packaging: blindly factor out trap's cleanup function in builddeb

This commit blindly extracts builddeb's trap routine in a dedicated function.
While doing so, I think two bugs are exposed, which will be addressed in the
next commits:

- single quoting around '$CLEANUP' will always evaluate to the literal
  '$CLEANUP' regardless of the variable's value. The "if" will always be true.
- the removal operation will not expand $PWD (and a variable expansion would
  need double quotes, anyways.

@echo off
rem Windows Driver script for Mercurial

setlocal
set HG=%~f0

rem Use a full path to Python (relative to this script) if it exists,
rem as the standard Python install does not put python.exe on the PATH...
rem Otherwise, expect that python.exe can be found on the PATH.
rem %~dp0 is the directory of this script

if exist "%~dp0..\python.exe" (
    "%~dp0..\python" "%~dp0hg" %*
) else (
    python "%~dp0hg" %*
)
endlocal

exit /b %ERRORLEVEL%