Merge remote-tracking branch 'upstream/master'

lib/grep.zsh

@@ -1,6 +1,28 @@
-#
-# Color grep results
-# Examples: http://rubyurl.com/ZXv
-#
-export GREP_OPTIONS='--color=auto'
-export GREP_COLOR='1;32'
+# is x grep argument available?
+grep-flag-available() {
+    echo | grep $1 "" >/dev/null 2>&1
+}
+
+GREP_OPTIONS=""
+
+# color grep results
+if grep-flag-available --color=auto; then
+    GREP_OPTIONS+=" --color=auto"
+fi
+
+# ignore VCS folders (if the necessary grep flags are available)
+VCS_FOLDERS="{.bzr,CVS,.git,.hg,.svn}"
+
+if grep-flag-available --exclude-dir=.cvs; then
+    GREP_OPTIONS+=" --exclude-dir=$VCS_FOLDERS"
+elif grep-flag-available --exclude=.cvs; then
+    GREP_OPTIONS+=" --exclude=$VCS_FOLDERS"
+fi
+
+# export grep settings
+alias grep="grep $GREP_OPTIONS"
+
+# clean up
+unset GREP_OPTIONS
+unset VCS_FOLDERS
+unfunction grep-flag-available