[magnum] Removing quotes around tools list where vcpkg_copy_tools is involked

[PhoebeHui]

Fixes #14329

emoving quotes around tools list where vcpkg_copy_tools is involked, see details in #14329 (comment)

[jgehw]

Sorry for not replying earlier (I didn't get notified that I was mentioned in the issue).

This is not the way we should fix it, because removing the backslashes is essentially a work-around to remove work-arounds in the portfiles, which aren't needed any more. Moreover, this could breaks things.

To explain the background, as it's really anything else than obvious:

• cmake uses semicolons as list separators
• => semicolons inside strings that a elements of a list must be escaped
• cmake has two bugs: correctly escaped semicolons get broken, if
  • cmake_parse_arguments is used not the PARSE_ARGV-way
  • lists are modified other than by appending, i.e. inserting
• That's why I fixed all cmake_parse_arguments in [vcpkg] Fix more cases of semicolon mishandling in "scripts" - follow-up to PR #12926 #13968
• various portfiles used work-arounds in the past to get around this, in particular, by passing a list as string, for example:

set(_TOOL_EXEC_NAMES "")
list(APPEND _TOOL_EXEC_NAMES "some_tool")
list(APPEND _TOOL_EXEC_NAMES "another_tool")
# passing ${_TOOL_EXEC_NAMES} would be passing the list
# passing "${_TOOL_EXEC_NAMES}" converts the list into a string
# so this way to invoke it is a work-around for the buggy cmake API
vcpkg_copy_tools(TOOL_NAMES "${_TOOL_EXEC_NAMES}" AUTO_CLEAN)
# now that the non-buggy version of cmake_parse_arguments is used, it must be invoked without string-conversion work-around
vcpkg_copy_tools(TOOL_NAMES ${_TOOL_EXEC_NAMES} AUTO_CLEAN)

• Thus, the way to fix this, is to remove the list-to-string-conversion work-around from the portfile, i.e. drop the quotes around tools list where vcpkg_copy_tools is invoked. In [vcpkg] Fix more cases of semicolon mishandling in "scripts" - follow-up to PR #12926 #13968 I was hoping to remove all such work-arounds from all portfiles, but apparently, I missed the magnum port.

Long story short: please fix by removing quotes in magnum portfile.

[PhoebeHui]

@jgehw, thanks for your review! I have updated the magnum port.

[BillyONeal]

Thanks :D