tests/run-test.sh: Add new tool to simplify running tests

Running the tests outside of meson gives more control but also requires
setting up a bunch of environment variables. The new script sets
everything up automatically if the standard build directory is used.

tests/run-test.sh

@@ -0,0 +1,30 @@
+#!/bin/bash
+#
+# - Sets up the required environment to run tests based on the build dir.
+# - If another build directory is used, it can be set in the BUILDDIR env
+#   variable.
+# - All arguments are passed along to pytest.
+# - Check tests/README.md for useful environment variables
+#
+# Examples:
+#
+#   ./run-test.sh ./test_camera.py -k test_version -v -s
+#
+#   BUILDDIR=../_build ./run-test.sh ./test_usb.py
+#
+
+set -euo pipefail
+
+SCRIPT_DIR=$( cd -- "$( dirname -- "${BASH_SOURCE[0]}" )" &> /dev/null && pwd )
+
+BUILDDIR="${BUILDDIR:-$SCRIPT_DIR/../build}"
+
+[ ! -d $BUILDDIR ] && echo "Env BUILDDIR must be set to the build dir" && exit 1
+
+export XDP_VALIDATE_SOUND=$BUILDDIR/src/xdg-desktop-portal-validate-sound
+export XDP_VALIDATE_ICON=$BUILDDIR/src/xdg-desktop-portal-validate-icon
+export XDG_DESKTOP_PORTAL_PATH=$BUILDDIR/src/xdg-desktop-portal
+export XDG_DOCUMENT_PORTAL_PATH=$BUILDDIR/document-portal/xdg-document-portal
+export XDG_PERMISSION_STORE_PATH=$BUILDDIR/document-portal/xdg-permission-store
+exec pytest-3 $@
+