From 7675e057d226c7c945d4a00141b2e132bf1a5aab Mon Sep 17 00:00:00 2001
From: Jason Perkins <starkos@industriousone.com>
Date: Thu, 26 Apr 2012 07:44:25 -0400
Subject: [PATCH] Deep copy all object values, to allow unique per-target token
 expansions

---
 src/base/table.lua         | 28 ++++++++++++++++++++++++++++
 src/project/oven.lua       | 10 ++++++----
 tests/oven/test_tokens.lua | 34 ++++++++++++++++++++++++++++++++++
 3 files changed, 68 insertions(+), 4 deletions(-)

diff --git a/src/base/table.lua b/src/base/table.lua
index 877fa689..63985554 100644
--- a/src/base/table.lua
+++ b/src/base/table.lua
@@ -18,7 +18,35 @@
 		return false
 	end
 	
+
+--
+-- Make a complete copy of a table, including any child tables it contains.
+--
+
+	function table.deepcopy(object)
+		-- keep track of already seen objects to avoid loops
+		local seen = {}
 		
+		local function copy(object)
+			if type(object) ~= "table" then
+				return object
+			elseif seen[object] then
+				return seen[object]
+			end
+			
+			local clone = {}
+			seen[object] = clone
+			for key, value in pairs(object) do
+				clone[key] = copy(value)
+			end
+			
+			return clone
+		end
+		
+		return copy(object)
+	end
+
+
 --
 -- Enumerates an array of objects and returns a new table containing
 -- only the value of one particular field.
diff --git a/src/project/oven.lua b/src/project/oven.lua
index 2b53f0cc..6393c4b6 100755
--- a/src/project/oven.lua
+++ b/src/project/oven.lua
@@ -122,7 +122,6 @@
 	function oven.expandtokens(cfg, scope, filecfg)
 		-- build a context for the tokens to use
 		local context = {
-			_G = _G,
 			sln = cfg.solution,
 			prj = cfg.project,
 			cfg = cfg,
@@ -163,7 +162,8 @@
 			
 			-- give the function access to the project objects
 			setfenv(func, context)
-								
+			setmetatable(context, {__index = _G})
+
 			-- run it and return the result
 			local result = func()
 			if not result then
@@ -395,11 +395,13 @@
 -- 
 
 	function oven.mergevalue(target, fieldname, fieldkind, value)
-		-- list values get merged, others overwrite
+		-- list values get merged, others overwrite; note that if the 
+		-- values contain tokens they will be modified in the token 
+		-- expansion phase, so important to make copies of objects
 		if fieldkind:endswith("list") then
 			target[fieldname] = oven.mergetables(target[fieldname] or {}, value)
 		else
-			target[fieldname] = value
+			target[fieldname] = table.deepcopy(value)
 		end
 	end
 
diff --git a/tests/oven/test_tokens.lua b/tests/oven/test_tokens.lua
index a796c35f..a0a317ab 100644
--- a/tests/oven/test_tokens.lua
+++ b/tests/oven/test_tokens.lua
@@ -85,3 +85,37 @@
 		local fcfg = config.getfileconfig(cfg, os.getcwd().."/shaders/hello.cg")
 		test.isequal("cgc --profile gp5vp shaders/hello.cg -o obj/Debug/hello.gxp", fcfg.buildrule.commands[1])
 	end
+
+
+--
+-- Make sure that the same token source can be applied to multiple targets.
+--
+
+	function suite.canReuseTokenSources()
+		files { "shaders/hello.cg", "shaders/goodbye.cg" }
+		configuration { "**.cg" }
+			buildrule {
+				commands = {
+					"cgc --profile gp5vp %{file.path} -o %{cfg.objdir}/%{file.basename}.gxp",
+				},
+				outputs = {
+					"%{cfg.objdir}/%{file.basename}.o"
+				}
+			}
+		prepare()
+		local fcfg = config.getfileconfig(cfg, os.getcwd().."/shaders/hello.cg")
+		test.isequal("cgc --profile gp5vp shaders/hello.cg -o obj/Debug/hello.gxp", fcfg.buildrule.commands[1])
+		fcfg = config.getfileconfig(cfg, os.getcwd().."/shaders/goodbye.cg")
+		test.isequal("cgc --profile gp5vp shaders/goodbye.cg -o obj/Debug/goodbye.gxp", fcfg.buildrule.commands[1])
+	end
+
+
+--
+-- Verify the global namespace is still accessible.
+--
+
+	function suite.canUseGlobalFunctions()
+		testapi "%{iif(true, 'a', 'b')}"
+		prepare()
+		test.isequal("a", cfg.testapi)
+	end