From 3370984c2444ac8b862da1fa69e96b4450d630c5 Mon Sep 17 00:00:00 2001
From: Yihui Xie <xie@yihui.name>
Date: Sat, 10 Mar 2012 23:37:08 -0600
Subject: [PATCH] completely fixes #138

---
 R/block.R | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/R/block.R b/R/block.R
index 72a596a828..48627a1ad8 100644
--- a/R/block.R
+++ b/R/block.R
@@ -95,6 +95,7 @@ block_exec = function(params) {
     options$fig.ext = dev2ext(options$dev)
   }
   
+  obj.before = ls(globalenv(), all.names = TRUE)  # global objects before chunk
   res.before = run_hooks(before = TRUE, options, env) # run 'before' hooks
   owd = setwd(input_dir())
   res = evaluate(code, envir = env) # run code
@@ -172,7 +173,8 @@ block_exec = function(params) {
   plot_counter(reset = TRUE)  # restore plot number
   
   if (options$cache) {
-    objs = ls(env, all.names = TRUE)
+    obj.after = ls(globalenv(), all.names = TRUE)  # figure out new global objs
+    objs = c(ls(env, all.names = TRUE), setdiff(obj.after, obj.before))
     block_cache(options, output, objs)
     if (options$autodep) cache$objects(objs, code, options$label, options$cache.path)
   }