[gentoo-dev] [PATCH 0/4] Eclass for single-impl Lua ebuilds

[Marek Szuba]

Same as lua.eclass and python-r1, this is a Lua version of
python-single-r1. Setting LUA_SINGLE_TARGETS allows one to choose the
(slotted) Lua implementation to build your ebuild against, optionally
including both single- and multi-implementation Lua packages as
dependencies.

Tested using modified ebuilds of the following packages:

 - dev-lua/lgi - the multi-impl package I previously used to test
   lua.eclass, rebuilt this time to make sure said eclass still works
   properly after having moved some variables and functions to
   lua-utils.eclass (it does);

 - x11-wm/awesome - single-implementation, unconditionally depends on
   both dev-lang/lua itself and dev-lua/lgi (as well as some other
   dev-lua packages used by the test suite, which however I ignored).
   Links fine against whichever Lua version is selected by
   LUA_SINGLE_TARGET, requiring correct LUA_TARGETS to be enabled for
   dev-lua/lgi in either case;

 - media-gfx/darktable - conditional dependency on dev-lang/lua
   controlled by USE=lua. Also builds fine, although with it only
   supporting lua-5.3+ there wasn't much I could do in terms of version
   switching beyond confirming that LUA_REQUIRED_USE correctly specifies
   that exactly one single target must be specified.