diff --git a/contrib/remote-helpers/test-hg-bidi.sh b/contrib/remote-helpers/test-hg-bidi.sh
new file mode 100755
index 0000000000..a94eb28092
--- /dev/null
+++ b/contrib/remote-helpers/test-hg-bidi.sh
@@ -0,0 +1,243 @@
+#!/bin/sh
+#
+# Copyright (c) 2012 Felipe Contreras
+#
+# Base commands from hg-git tests:
+# https://bitbucket.org/durin42/hg-git/src
+#
+
+test_description='Test biridectionality of remote-hg'
+
+. ./test-lib.sh
+
+if ! test_have_prereq PYTHON; then
+	skip_all='skipping remote-hg tests; python not available'
+	test_done
+fi
+
+if ! "$PYTHON_PATH" -c 'import mercurial'; then
+	skip_all='skipping remote-hg tests; mercurial not available'
+	test_done
+fi
+
+# clone to a git repo
+git_clone () {
+	hg -R $1 bookmark -f -r tip master &&
+	git clone -q "hg::$PWD/$1" $2
+}
+
+# clone to an hg repo
+hg_clone () {
+	(
+	hg init $2 &&
+	cd $1 &&
+	git push -q "hg::$PWD/../$2" 'refs/tags/*:refs/tags/*' 'refs/heads/*:refs/heads/*'
+	) &&
+
+	(cd $2 && hg -q update)
+}
+
+# push an hg repo
+hg_push () {
+	(
+	cd $2
+	old=$(git symbolic-ref --short HEAD)
+	git checkout -q -b tmp &&
+	git fetch -q "hg::$PWD/../$1" 'refs/tags/*:refs/tags/*' 'refs/heads/*:refs/heads/*' &&
+	git checkout -q $old &&
+	git branch -q -D tmp 2> /dev/null || true
+	)
+}
+
+hg_log () {
+	hg -R $1 log --graph --debug | grep -v 'tag: *default/'
+}
+
+setup () {
+	(
+	echo "[ui]"
+	echo "username = A U Thor <author@example.com>"
+	echo "[defaults]"
+	echo "backout = -d \"0 0\""
+	echo "commit = -d \"0 0\""
+	echo "debugrawcommit = -d \"0 0\""
+	echo "tag = -d \"0 0\""
+	) >> "$HOME"/.hgrc &&
+	git config --global remote-hg.hg-git-compat true
+
+	export HGEDITOR=/usr/bin/true
+
+	export GIT_AUTHOR_DATE="2007-01-01 00:00:00 +0230"
+	export GIT_COMMITTER_DATE="$GIT_AUTHOR_DATE"
+}
+
+setup
+
+test_expect_success 'encoding' '
+	mkdir -p tmp && cd tmp &&
+	test_when_finished "cd .. && rm -rf tmp" &&
+
+	(
+	git init -q gitrepo &&
+	cd gitrepo &&
+
+	echo alpha > alpha &&
+	git add alpha &&
+	git commit -m "add älphà" &&
+
+	export GIT_AUTHOR_NAME="tést èncödîng" &&
+	echo beta > beta &&
+	git add beta &&
+	git commit -m "add beta" &&
+
+	echo gamma > gamma &&
+	git add gamma &&
+	git commit -m "add gämmâ" &&
+
+	: TODO git config i18n.commitencoding latin-1 &&
+	echo delta > delta &&
+	git add delta &&
+	git commit -m "add déltà"
+	) &&
+
+	hg_clone gitrepo hgrepo &&
+	git_clone hgrepo gitrepo2 &&
+	hg_clone gitrepo2 hgrepo2 &&
+
+	HGENCODING=utf-8 hg_log hgrepo > expected &&
+	HGENCODING=utf-8 hg_log hgrepo2 > actual &&
+
+	test_cmp expected actual
+'
+
+test_expect_success 'file removal' '
+	mkdir -p tmp && cd tmp &&
+	test_when_finished "cd .. && rm -rf tmp" &&
+
+	(
+	git init -q gitrepo &&
+	cd gitrepo &&
+	echo alpha > alpha &&
+	git add alpha &&
+	git commit -m "add alpha" &&
+	echo beta > beta &&
+	git add beta &&
+	git commit -m "add beta"
+	mkdir foo &&
+	echo blah > foo/bar &&
+	git add foo &&
+	git commit -m "add foo" &&
+	git rm alpha &&
+	git commit -m "remove alpha" &&
+	git rm foo/bar &&
+	git commit -m "remove foo/bar"
+	) &&
+
+	hg_clone gitrepo hgrepo &&
+	git_clone hgrepo gitrepo2 &&
+	hg_clone gitrepo2 hgrepo2 &&
+
+	hg_log hgrepo > expected &&
+	hg_log hgrepo2 > actual &&
+
+	test_cmp expected actual
+'
+
+test_expect_success 'git tags' '
+	mkdir -p tmp && cd tmp &&
+	test_when_finished "cd .. && rm -rf tmp" &&
+
+	(
+	git init -q gitrepo &&
+	cd gitrepo &&
+	git config receive.denyCurrentBranch ignore &&
+	echo alpha > alpha &&
+	git add alpha &&
+	git commit -m "add alpha" &&
+	git tag alpha &&
+
+	echo beta > beta &&
+	git add beta &&
+	git commit -m "add beta" &&
+	git tag -a -m "added tag beta" beta
+	) &&
+
+	hg_clone gitrepo hgrepo &&
+	git_clone hgrepo gitrepo2 &&
+	hg_clone gitrepo2 hgrepo2 &&
+
+	hg_log hgrepo > expected &&
+	hg_log hgrepo2 > actual &&
+
+	test_cmp expected actual
+'
+
+test_expect_success 'hg branch' '
+	mkdir -p tmp && cd tmp &&
+	test_when_finished "cd .. && rm -rf tmp" &&
+
+	(
+	git init -q gitrepo &&
+	cd gitrepo &&
+
+	echo alpha > alpha &&
+	git add alpha &&
+	git commit -q -m "add alpha" &&
+	git checkout -q -b not-master
+	) &&
+
+	(
+	hg_clone gitrepo hgrepo &&
+
+	cd hgrepo &&
+	hg -q co master &&
+	hg mv alpha beta &&
+	hg -q commit -m "rename alpha to beta" &&
+	hg branch gamma | grep -v "permanent and global" &&
+	hg -q commit -m "started branch gamma"
+	) &&
+
+	hg_push hgrepo gitrepo &&
+	hg_clone gitrepo hgrepo2 &&
+
+	: TODO, avoid "master" bookmark &&
+	(cd hgrepo2 && hg checkout gamma) &&
+
+	hg_log hgrepo > expected &&
+	hg_log hgrepo2 > actual &&
+
+	test_cmp expected actual
+'
+
+test_expect_success 'hg tags' '
+	mkdir -p tmp && cd tmp &&
+	test_when_finished "cd .. && rm -rf tmp" &&
+
+	(
+	git init -q gitrepo &&
+	cd gitrepo &&
+
+	echo alpha > alpha &&
+	git add alpha &&
+	git commit -m "add alpha" &&
+	git checkout -q -b not-master
+	) &&
+
+	(
+	hg_clone gitrepo hgrepo &&
+
+	cd hgrepo &&
+	hg co master &&
+	hg tag alpha
+	) &&
+
+	hg_push hgrepo gitrepo &&
+	hg_clone gitrepo hgrepo2 &&
+
+	hg_log hgrepo > expected &&
+	hg_log hgrepo2 > actual &&
+
+	test_cmp expected actual
+'
+
+test_done