Add gsync function for upstream Git branch syncer.

.bash_profile

@@ -58,6 +58,25 @@ alias gl='git log --graph --pretty=format:"%Cred%h%Creset -%C(yellow)%d%Creset %
 alias gsd='git svn dcommit'
 alias gsfr='git svn fetch && git svn rebase'
 
+# Git upstream branch syncer.
+# Usage: gsync master (checks out master, pull upstream, push origin).
+function gsync() {
+  if [[ ! "$1" ]] ; then
+      echo "You must supply a branch."
+      return 0
+  fi
+
+  BRANCHES=$(git branch --list $1)
+  if [ ! "$BRANCHES" ] ; then
+     echo "Branch $1 does not exist."
+     return 0
+  fi
+
+  git checkout "$1" && \
+  git pull upstream "$1" && \
+  git push origin "$1"
+}
+
 # Turn on Git autocomplete.
 brew_prefix=`brew --prefix`
 if [ -f $brew_prefix/etc/bash_completion ]; then