Use premake5 beta2's externalincludedirs when available

As of the `beta2` version of `premake5`, `sysincludedirs` has been
deprecated
and replaced with/renamed to `externalincludedirs`, and continuing to
use it
causes warnings to be emitted.

With this change, we now use `externalincludedirs` when available so as
to
prevent the warnings, falling back to `sysincludedirs` when it's not to
prevent
breakage with pre-`beta2` versions of `premake5`.


Accepted By: sera
Fixes: #6785
Differential Revision: https://code.wildfiregames.com/D4980
This was SVN commit r27606.

build/premake/extern_libs5.lua

@@ -26,15 +26,33 @@ local function add_source_lib_paths(extern_lib)
 end
 
 local function add_default_include_paths(extern_lib)
-	sysincludedirs { libraries_dir .. extern_lib .. "/include" }
+	-- As of premake5-beta2, `sysincludedirs` has been deprecated in favour of
+	-- `externalincludedirs`, and continuing to use it causes warnings to be emitted.
+	--
+	-- We use `externalincludedirs` when available to prevent the warnings, falling back
+	-- to `sysincludedirs` when not to prevent breakage of the `--with-system-premake5`
+	-- build argument.
+	if externalincludedirs then
+		externalincludedirs { libraries_dir .. extern_lib .. "/include" }
+	else
+		sysincludedirs { libraries_dir .. extern_lib .. "/include" }
+	end
 end
 
 local function add_source_include_paths(extern_lib)
-	sysincludedirs { libraries_source_dir .. extern_lib .. "/include" }
+	if externalincludedirs then
+		externalincludedirs { libraries_source_dir .. extern_lib .. "/include" }
+	else
+		sysincludedirs { libraries_source_dir .. extern_lib .. "/include" }
+	end
 end
 
 local function add_third_party_include_paths(extern_lib)
-	sysincludedirs { third_party_source_dir .. extern_lib .. "/include" }
+	if externalincludedirs then
+		externalincludedirs { third_party_source_dir .. extern_lib .. "/include" }
+	else
+		sysincludedirs { third_party_source_dir .. extern_lib .. "/include" }
+	end
 end
 
 pkgconfig = require "pkgconfig"
@@ -198,7 +216,11 @@ extern_lib_defs = {
 			end
 			-- TODO: This actually applies to most libraries we use on BSDs, make this a global setting.
 			if os.istarget("bsd") then
-				sysincludedirs { "/usr/local/include" }
+				if externalincludedirs then
+					externalincludedirs { "/usr/local/include" }
+				else
+					sysincludedirs { "/usr/local/include" }
+				end
 			end
 		end,
 		link_settings = function()
@@ -228,7 +250,11 @@ extern_lib_defs = {
 	},
 	cxxtest = {
 		compile_settings = function()
-			sysincludedirs { libraries_source_dir .. "cxxtest-4.4" }
+			if externalincludedirs then
+				externalincludedirs { libraries_source_dir .. "cxxtest-4.4" }
+			else
+				sysincludedirs { libraries_source_dir .. "cxxtest-4.4" }
+			end
 		end,
 	},
 	enet = {
@@ -609,10 +635,18 @@ extern_lib_defs = {
 					include_dir = "include-unix"
 				end
 				filter "Debug"
-					sysincludedirs { libraries_source_dir.."spidermonkey/"..include_dir.."-debug" }
+					if externalincludedirs then
+						externalincludedirs { libraries_source_dir.."spidermonkey/"..include_dir.."-debug" }
+					else
+						sysincludedirs { libraries_source_dir.."spidermonkey/"..include_dir.."-debug" }
+					end
 					defines { "DEBUG" }
 				filter "Release"
-					sysincludedirs { libraries_source_dir.."spidermonkey/"..include_dir.."-release" }
+					if externalincludedirs then
+						externalincludedirs { libraries_source_dir.."spidermonkey/"..include_dir.."-release" }
+					else
+						sysincludedirs { libraries_source_dir.."spidermonkey/"..include_dir.."-release" }
+					end
 				filter { }
 			end
 		end,

build/premake/pkgconfig/pkgconfig.lua

@@ -1,5 +1,5 @@
 local m = {}
-m._VERSION = "1.1.1-dev"
+m._VERSION = "1.1.2-dev"
 
 m.additional_pc_path = nil
 m.static_link_libs = false
@@ -38,7 +38,17 @@ function m.add_includes(lib, alternative_cmd, alternative_flags)
 		end
 	end
 
-	sysincludedirs(dirs)
+	-- As of premake5-beta2, `sysincludedirs` has been deprecated in favour of
+	-- `externalincludedirs`, and continuing to use it causes warnings to be emitted.
+	-- We use `externalincludedirs` when available to prevent the warnings, falling back
+	-- to `sysincludedirs` when not to prevent breakage of the `--with-system-premake5`
+	-- build argument.
+	if externalincludedirs then
+		externalincludedirs(dirs)
+	else
+		sysincludedirs(dirs)
+	end
+
 	forceincludes(files)
 	buildoptions(options)
 end

build/premake/premake5.lua

@@ -945,7 +945,11 @@ function setup_all_libs ()
 	end
 	setup_static_lib_project("gladwrapper", {}, used_extern_libs, { no_pch = 1 })
 	glad_path = libraries_source_dir.."glad/"
-	sysincludedirs { glad_path.."include" }
+	if externalincludedirs then
+		externalincludedirs { glad_path.."include" }
+	else
+		sysincludedirs { glad_path.."include" }
+	end
 	files { glad_path.."src/vulkan.cpp" }
 	if _OPTIONS["gles"] then
 		files { glad_path.."src/gles2.cpp" }