diff --git a/contrib/completion/git-completion.bash b/contrib/completion/git-completion.bash
new file mode 100755
index 0000000000..d9cb17d0b2
--- /dev/null
+++ b/contrib/completion/git-completion.bash
@@ -0,0 +1,324 @@
+#
+# bash completion support for core Git.
+#
+# Copyright (C) 2006 Shawn Pearce
+# Conceptually based on gitcompletion (http://gitweb.hawaga.org.uk/).
+#
+# The contained completion routines provide support for completing:
+#
+#    *) local and remote branch names
+#    *) local and remote tag names
+#    *) .git/remotes file names
+#    *) git 'subcommands'
+#    *) tree paths within 'ref:path/to/file' expressions
+#
+# To use these routines:
+#
+#    1) Copy this file to somewhere (e.g. ~/.git-completion.sh).
+#    2) Added the following line to your .bashrc:
+#        source ~/.git-completion.sh
+#
+
+__git_refs ()
+{
+	local cmd i is_hash=y
+	if [ -d "$1" ]; then
+		cmd=git-peek-remote
+	else
+		cmd=git-ls-remote
+	fi
+	for i in $($cmd "$1" 2>/dev/null); do
+		case "$is_hash,$i" in
+		y,*) is_hash=n ;;
+		n,*^{}) is_hash=y ;;
+		n,refs/tags/*) is_hash=y; echo "${i#refs/tags/}" ;;
+		n,refs/heads/*) is_hash=y; echo "${i#refs/heads/}" ;;
+		n,*) is_hash=y; echo "$i" ;;
+		esac
+	done
+}
+
+__git_refs2 ()
+{
+	local cmd i is_hash=y
+	if [ -d "$1" ]; then
+		cmd=git-peek-remote
+	else
+		cmd=git-ls-remote
+	fi
+	for i in $($cmd "$1" 2>/dev/null); do
+		case "$is_hash,$i" in
+		y,*) is_hash=n ;;
+		n,*^{}) is_hash=y ;;
+		n,refs/tags/*) is_hash=y; echo "${i#refs/tags/}:${i#refs/tags/}" ;;
+		n,refs/heads/*) is_hash=y; echo "${i#refs/heads/}:${i#refs/heads/}" ;;
+		n,*) is_hash=y; echo "$i:$i" ;;
+		esac
+	done
+}
+
+__git_remotes ()
+{
+	local i REVERTGLOB=$(shopt -p nullglob)
+	shopt -s nullglob
+	for i in .git/remotes/*; do
+		echo ${i#.git/remotes/}
+	done
+	$REVERTGLOB
+}
+
+__git_complete_file ()
+{
+	local cur="${COMP_WORDS[COMP_CWORD]}"
+	case "$cur" in
+	?*:*)
+		local pfx ls ref="$(echo "$cur" | sed 's,:.*$,,')"
+		cur="$(echo "$cur" | sed 's,^.*:,,')"
+		case "$cur" in
+		?*/*)
+			pfx="$(echo "$cur" | sed 's,/[^/]*$,,')"
+			cur="$(echo "$cur" | sed 's,^.*/,,')"
+			ls="$ref:$pfx"
+			pfx="$pfx/"
+			;;
+		*)
+			ls="$ref"
+			;;
+	    esac
+		COMPREPLY=($(compgen -P "$pfx" \
+			-W "$(git-ls-tree "$ls" \
+				| sed '/^100... blob /s,^.*	,,
+				       /^040000 tree /{
+				           s,^.*	,,
+				           s,$,/,
+				       }
+				       s/^.*	//')" \
+			-- "$cur"))
+		;;
+	*)
+		COMPREPLY=($(compgen -W "$(__git_refs .)" -- "$cur"))
+		;;
+	esac
+}
+
+_git_branch ()
+{
+	local cur="${COMP_WORDS[COMP_CWORD]}"
+	COMPREPLY=($(compgen -W "-l -f -d -D $(__git_refs .)" -- "$cur"))
+}
+
+_git_cat_file ()
+{
+	local cur="${COMP_WORDS[COMP_CWORD]}"
+	case "${COMP_WORDS[0]},$COMP_CWORD" in
+	git-cat-file*,1)
+		COMPREPLY=($(compgen -W "-p -t blob tree commit tag" -- "$cur"))
+		;;
+	git,2)
+		COMPREPLY=($(compgen -W "-p -t blob tree commit tag" -- "$cur"))
+		;;
+	*)
+		__git_complete_file
+		;;
+	esac
+}
+
+_git_checkout ()
+{
+	local cur="${COMP_WORDS[COMP_CWORD]}"
+	COMPREPLY=($(compgen -W "-l -b $(__git_refs .)" -- "$cur"))
+}
+
+_git_diff ()
+{
+	__git_complete_file
+}
+
+_git_diff_tree ()
+{
+	local cur="${COMP_WORDS[COMP_CWORD]}"
+	COMPREPLY=($(compgen -W "-r -p -M $(__git_refs .)" -- "$cur"))
+}
+
+_git_fetch ()
+{
+	local cur="${COMP_WORDS[COMP_CWORD]}"
+
+	case "${COMP_WORDS[0]},$COMP_CWORD" in
+	git-fetch*,1)
+		COMPREPLY=($(compgen -W "$(__git_remotes)" -- "$cur"))
+		;;
+	git,2)
+		COMPREPLY=($(compgen -W "$(__git_remotes)" -- "$cur"))
+		;;
+	*)
+		case "$cur" in
+		*:*)
+	        cur=$(echo "$cur" | sed 's/^.*://')
+			COMPREPLY=($(compgen -W "$(__git_refs .)" -- "$cur"))
+			;;
+		*)
+			local remote
+			case "${COMP_WORDS[0]}" in
+			git-fetch) remote="${COMP_WORDS[1]}" ;;
+			git)       remote="${COMP_WORDS[2]}" ;;
+			esac
+			COMPREPLY=($(compgen -W "$(__git_refs2 "$remote")" -- "$cur"))
+			;;
+		esac
+		;;
+	esac
+}
+
+_git_ls_remote ()
+{
+	local cur="${COMP_WORDS[COMP_CWORD]}"
+	COMPREPLY=($(compgen -W "$(__git_remotes)" -- "$cur"))
+}
+
+_git_ls_tree ()
+{
+	__git_complete_file
+}
+
+_git_log ()
+{
+	local cur="${COMP_WORDS[COMP_CWORD]}"
+	case "$cur" in
+	*..*)
+		local pfx=$(echo "$cur" | sed 's/\.\..*$/../')
+		cur=$(echo "$cur" | sed 's/^.*\.\.//')
+		COMPREPLY=($(compgen -P "$pfx" -W "$(__git_refs .)" -- "$cur"))
+		;;
+	*)
+		COMPREPLY=($(compgen -W "$(__git_refs .)" -- "$cur"))
+		;;
+	esac
+}
+
+_git_merge_base ()
+{
+	local cur="${COMP_WORDS[COMP_CWORD]}"
+	COMPREPLY=($(compgen -W "$(__git_refs .)" -- "$cur"))
+}
+
+_git_pull ()
+{
+	local cur="${COMP_WORDS[COMP_CWORD]}"
+
+	case "${COMP_WORDS[0]},$COMP_CWORD" in
+	git-pull*,1)
+		COMPREPLY=($(compgen -W "$(__git_remotes)" -- "$cur"))
+		;;
+	git,2)
+		COMPREPLY=($(compgen -W "$(__git_remotes)" -- "$cur"))
+		;;
+	*)
+		local remote
+		case "${COMP_WORDS[0]}" in
+		git-pull)  remote="${COMP_WORDS[1]}" ;;
+		git)       remote="${COMP_WORDS[2]}" ;;
+		esac
+		COMPREPLY=($(compgen -W "$(__git_refs "$remote")" -- "$cur"))
+		;;
+	esac
+}
+
+_git_push ()
+{
+	local cur="${COMP_WORDS[COMP_CWORD]}"
+
+	case "${COMP_WORDS[0]},$COMP_CWORD" in
+	git-push*,1)
+		COMPREPLY=($(compgen -W "$(__git_remotes)" -- "$cur"))
+		;;
+	git,2)
+		COMPREPLY=($(compgen -W "$(__git_remotes)" -- "$cur"))
+		;;
+	*)
+		case "$cur" in
+		*:*)
+			local remote
+			case "${COMP_WORDS[0]}" in
+			git-push)  remote="${COMP_WORDS[1]}" ;;
+			git)       remote="${COMP_WORDS[2]}" ;;
+			esac
+	        cur=$(echo "$cur" | sed 's/^.*://')
+			COMPREPLY=($(compgen -W "$(__git_refs "$remote")" -- "$cur"))
+			;;
+		*)
+			COMPREPLY=($(compgen -W "$(__git_refs2 .)" -- "$cur"))
+			;;
+		esac
+		;;
+	esac
+}
+
+_git_show ()
+{
+	local cur="${COMP_WORDS[COMP_CWORD]}"
+	COMPREPLY=($(compgen -W "$(__git_refs .)" -- "$cur"))
+}
+
+_git ()
+{
+	if [ $COMP_CWORD = 1 ]; then
+		COMPREPLY=($(compgen \
+			-W "--version $(git help -a|egrep '^ ')" \
+			-- "${COMP_WORDS[COMP_CWORD]}"))
+	else
+		case "${COMP_WORDS[1]}" in
+		branch)      _git_branch ;;
+		cat-file)    _git_cat_file ;;
+		checkout)    _git_checkout ;;
+		diff)        _git_diff ;;
+		diff-tree)   _git_diff_tree ;;
+		fetch)       _git_fetch ;;
+		log)         _git_log ;;
+		ls-remote)   _git_ls_remote ;;
+		ls-tree)     _git_ls_tree ;;
+		pull)        _git_pull ;;
+		push)        _git_push ;;
+		show)        _git_show ;;
+		show-branch) _git_log ;;
+		whatchanged) _git_log ;;
+		*)           COMPREPLY=() ;;
+		esac
+	fi
+}
+
+_gitk ()
+{
+	local cur="${COMP_WORDS[COMP_CWORD]}"
+	COMPREPLY=($(compgen -W "--all $(__git_refs .)" -- "$cur"))
+}
+
+complete -o default -o nospace -F _git git
+complete -o default            -F _gitk gitk
+complete -o default            -F _git_branch git-branch
+complete -o default -o nospace -F _git_cat_file git-cat-file
+complete -o default            -F _git_checkout git-checkout
+complete -o default -o nospace -F _git_diff git-diff
+complete -o default            -F _git_diff_tree git-diff-tree
+complete -o default -o nospace -F _git_fetch git-fetch
+complete -o default -o nospace -F _git_log git-log
+complete -o default            -F _git_ls_remote git-ls-remote
+complete -o default -o nospace -F _git_ls_tree git-ls-tree
+complete -o default            -F _git_merge_base git-merge-base
+complete -o default -o nospace -F _git_pull git-pull
+complete -o default -o nospace -F _git_push git-push
+complete -o default            -F _git_show git-show
+complete -o default -o nospace -F _git_log git-whatchanged
+
+# The following are necessary only for Cygwin, and only are needed
+# when the user has tab-completed the executable name and consequently
+# included the '.exe' suffix.
+#
+complete -o default -o nospace -F _git_cat_file git-cat-file.exe
+complete -o default -o nospace -F _git_diff git-diff.exe
+complete -o default -o nospace -F _git_diff_tree git-diff-tree.exe
+complete -o default -o nospace -F _git_log git-log.exe
+complete -o default -o nospace -F _git_ls_tree git-ls-tree.exe
+complete -o default            -F _git_merge_base git-merge-base.exe
+complete -o default -o nospace -F _git_push git-push.exe
+complete -o default -o nospace -F _git_log git-whatchanged.exe