Implemented VS API for toggling of C++20 modules and STL module build (…

…#2130)

modules/vstudio/_preload.lua

@@ -195,6 +195,26 @@
 		}
 	}
 
+	p.api.register {
+		name = "enablemodules",
+		scope = { "config" },
+		kind = "string",
+		allowed = {
+			"On",
+			"Off"
+		}
+	}
+
+	p.api.register {
+		name = "buildstlmodules",
+		scope = { "config" },
+		kind = "string",
+		allowed = {
+			"On",
+			"Off"
+		}
+	}
+
 --
 -- Decide when the full module should be loaded.
 --

modules/vstudio/tests/vc2019/test_compile_settings.lua

@@ -148,3 +148,29 @@
 	<UseStandardPreprocessor>false</UseStandardPreprocessor>
 		]]
 	end
+
+	function suite.enableModulesOff()
+		enablemodules 'Off'
+		prepare()
+		test.capture [[
+<ClCompile>
+	<PrecompiledHeader>NotUsing</PrecompiledHeader>
+	<WarningLevel>Level3</WarningLevel>
+	<Optimization>Disabled</Optimization>
+	<ExternalWarningLevel>Level3</ExternalWarningLevel>
+	<EnableModules>false</EnableModules>
+		]]
+	end
+
+	function suite.enableModulesOn()
+		enablemodules 'On'
+		prepare()
+		test.capture [[
+<ClCompile>
+	<PrecompiledHeader>NotUsing</PrecompiledHeader>
+	<WarningLevel>Level3</WarningLevel>
+	<Optimization>Disabled</Optimization>
+	<ExternalWarningLevel>Level3</ExternalWarningLevel>
+	<EnableModules>true</EnableModules>
+		]]
+	end

modules/vstudio/tests/vc2022/test_compile_settings.lua

@@ -160,3 +160,29 @@ function suite.TreatAngleIncludeAsExternalOffFile()
 		<TreatAngleIncludeAsExternal>false</TreatAngleIncludeAsExternal>
 	]]
 end
+
+function suite.BuildStlModulesOff()
+	buildstlmodules 'Off'
+	prepare()
+	test.capture [[
+<ClCompile>
+	<PrecompiledHeader>NotUsing</PrecompiledHeader>
+	<WarningLevel>Level3</WarningLevel>
+	<Optimization>Disabled</Optimization>
+	<ExternalWarningLevel>Level3</ExternalWarningLevel>
+	<BuildStlModules>false</BuildStlModules>
+	]]
+end
+
+function suite.BuildStlModulesOn()
+	buildstlmodules 'On'
+	prepare()
+	test.capture [[
+<ClCompile>
+	<PrecompiledHeader>NotUsing</PrecompiledHeader>
+	<WarningLevel>Level3</WarningLevel>
+	<Optimization>Disabled</Optimization>
+	<ExternalWarningLevel>Level3</ExternalWarningLevel>
+	<BuildStlModules>true</BuildStlModules>
+	]]
+end

modules/vstudio/vs2010_vcxproj.lua

@@ -408,6 +408,8 @@
 			m.externalAngleBrackets,
 			m.scanSourceForModuleDependencies,
 			m.useStandardPreprocessor,
+			m.enableModules,
+			m.buildStlModules,
 		}
 
 		if cfg.kind == p.STATICLIB then
@@ -3029,6 +3031,24 @@
 	end
 
 
+	function m.enableModules(cfg)
+		if _ACTION >= "vs2019" then
+			if cfg.enablemodules then
+				m.element("EnableModules", nil, iif(cfg.enablemodules == "On", "true", "false"))
+			end
+		end
+	end
+
+
+	function m.buildStlModules(cfg)
+		if _ACTION >= "vs2022" then
+			if cfg.buildstlmodules then
+				m.element("BuildStlModules", nil, iif(cfg.buildstlmodules == "On", "true", "false"))
+			end
+		end
+	end
+
+
 	function m.externalAngleBrackets(cfg, condition)
 		if _ACTION >= "vs2019" then
 			if cfg.externalanglebrackets == p.OFF then

website/docs/buildstlmodules.md

@@ -0,0 +1,24 @@
+Sets whether or not the compiler should build STL modules.
+
+```lua
+buildstlmodules("value")
+```
+
+### Parameters ###
+
+`value` is one of:
+
+- `On`
+- `Off`
+
+### Applies To ###
+
+The `config` scope.
+
+### Availability ###
+
+Premake 5.0.0 beta 3 or later for Visual Studio 2022 and later.
+
+### See Also ###
+
+* [enablemodules](enablemodules.md)

website/docs/enablemodules.md

@@ -0,0 +1,20 @@
+Sets whether or not the compiler should enable C++20 modules.
+
+```lua
+enablemodules("value")
+```
+
+### Parameters ###
+
+`value` is one of:
+
+- `On`
+- `Off`
+
+### Applies To ###
+
+The `config` scope.
+
+### Availability ###
+
+Premake 5.0.0 beta 3 or later for Visual Studio 2019 and later.

website/sidebars.js

@@ -80,6 +80,7 @@ module.exports = {
 						'buildoptions',
 						'buildoutputs',
 						'buildrule',
+						'buildstlmodules',
 						'callingconvention',
 						'cdialect',
 						'characterset',
@@ -139,6 +140,7 @@ module.exports = {
 						'embed',
 						'embedandsign',
 						'enabledefaultcompileitems',
+						'enablemodules',
 						'enableunitybuild',
 						'enablewarnings',
 						'endian',