Fixes for VC2010 custom build rule handling

src/actions/vstudio/vs2010_vcxproj.lua

@@ -420,12 +420,13 @@
 				for cfg in project.eachconfig(prj) do
 					local condition = vc2010.condition(cfg)					
 					local filecfg = config.getfileconfig(cfg, file.abspath)
-					
-					local commands = table.concat(filecfg.buildrule.commands,'\r\n')
-					_p(3,'<Command %s>%s</Command>', condition, premake.esc(commands))
-
-					local outputs = table.concat(filecfg.buildrule.outputs, ' ')
-					_p(3,'<Outputs %s>%s</Outputs>', condition, premake.esc(outputs))
+					if filecfg and filecfg.buildrule then
+						local commands = table.concat(filecfg.buildrule.commands,'\r\n')
+						_p(3,'<Command %s>%s</Command>', condition, premake.esc(commands))
+	
+						local outputs = table.concat(filecfg.buildrule.outputs, ' ')
+						_p(3,'<Outputs %s>%s</Outputs>', condition, premake.esc(outputs))
+					end
 				end
 				
 				_p(2,'</CustomBuild>')
@@ -447,17 +448,21 @@
 			}
 			prj.vc2010_file_groups = groups
 			
-			-- I need a project configuration in order to fetch a file's configuration,
-			-- which would contain any custom build rules. I'm hoping that I can get
-			-- away with only looking at the first config, and not iterating them all
-			local iter = project.eachconfig(prj)
-			local cfg = iter()
-
 			local tr = project.getsourcetree(prj)
 			tree.traverse(tr, {
 				onleaf = function(node)
-					local filecfg = config.getfileconfig(cfg, node.abspath)
-					if filecfg and filecfg.buildrule then
+					-- if any configuration of this file uses a custom build rule,
+					-- then they all must be marked as custom build
+					local hasbuildrule = false
+					for cfg in project.eachconfig(prj) do				
+						local filecfg = config.getfileconfig(cfg, node.abspath)
+						if filecfg and filecfg.buildrule then
+							hasbuildrule = true
+							break
+						end
+					end
+						
+					if hasbuildrule then
 						table.insert(groups.CustomBuild, node)
 					elseif path.iscppfile(node.name) then
 						table.insert(groups.ClCompile, node)

src/actions/vstudio/vs2010_vcxproj_filters.lua

@@ -24,6 +24,7 @@
 		vc2010.filters_filegroup(prj, "ClInclude")
 		vc2010.filters_filegroup(prj, "ClCompile")
 		vc2010.filters_filegroup(prj, "ResourceCompile")
+		vc2010.filters_filegroup(prj, "CustomBuild")
 		
 		_p('</Project>')
 	end

tests/actions/vstudio/vc2010/test_filters.lua

@@ -80,6 +80,21 @@
 		]]
 	end
 
+	function suite.itemGroup_onSingleConfigBuildRule()
+		files { "hello.c", "hello.h", "hello.rc", "hello.cg" }
+		configuration { "Release", "**.cg" }
+			buildrule {
+				commands = { "cgc $(InputFile)" },
+				outputs = { "$(InputName).obj" }
+			}
+		prepare("CustomBuild")
+		test.capture [[
+	<ItemGroup>
+		<CustomBuild Include="hello.cg" />
+	</ItemGroup>
+		]]
+	end
+
 
 --
 -- Files located at the root (in the same folder as the project) do not