tests: Add a stub test framework

Imported a little bit of code from OSTree's shell `libtest.sh`.  I'm
mostly doing this to test Travis and Homu, but hey, we get a little
bit of coverage.

Pull request: #21
Approved by: alexlarsson

Makefile.am

@@ -13,3 +13,6 @@ test-setcaps: bwrap
 	sudo setcap "cap_sys_admin+ep cap_sys_chroot+ep" bwrap
 
 include Makefile-docs.am
+
+TESTS = tests/test-basic.sh
+TESTS_ENVIRONMENT = PATH=$$(cd $(top_builddir) && pwd):$${PATH}

tests/test-basic.sh

@@ -0,0 +1,35 @@
+#!/bin/bash
+
+set -xeuo pipefail
+
+srcd=$(cd $(dirname $0) && pwd)
+bn=$(basename $0)
+tempdir=$(mktemp -d /var/tmp/tap-test.XXXXXX)
+touch ${tempdir}/.testtmp
+function cleanup () {
+    if test -n "${TEST_SKIP_CLEANUP:-}"; then
+	echo "Skipping cleanup of ${test_tmpdir}"
+    else if test -f ${tempdir}/.test; then
+	rm "${tempdir}" -rf
+    fi
+    fi
+}
+trap cleanup EXIT
+cd ${tempdir}
+
+assert_not_reached () {
+    echo $@ 1>&2; exit 1
+}
+
+assert_file_has_content () {
+    if ! grep -q -e "$2" "$1"; then
+	echo 1>&2 "File '$1' doesn't match regexp '$2'"; exit 1
+    fi
+}
+
+# At the moment we're testing in Travis' container infrastructure
+# which also uses PR_SET_NO_NEW_PRIVS...but let's at least
+# verify --help works!
+bwrap --help >out.txt 2>&1
+assert_file_has_content out.txt "--lock-file"
+