Adds write permission test on ~/.bash_profile prior to backup attempt. Fixes #199.

diff --git a/install.sh b/install.sh
index 0f1da39..46edcf2 100755 (executable)
--- a/install.sh
+++ b/install.sh
@@ -1,9 +1,9 @@
 #!/usr/bin/env bash
 BASH_IT="$HOME/.bash_it"
 
-cp $HOME/.bash_profile $HOME/.bash_profile.bak
-
-echo "Your original .bash_profile has been backed up to .bash_profile.bak"
+test -w $HOME/.bash_profile &&
+  cp $HOME/.bash_profile $HOME/.bash_profile.bak &&
+  echo "Your original .bash_profile has been backed up to .bash_profile.bak"
 
 cp $HOME/.bash_it/template/bash_profile.template.bash $HOME/.bash_profile