aes2550: Add basic test to check too-short errors

Traces provided by Shengyu Qu

Co-Authored-By: Shengyu Qu <wiagn@4d2.org>

tests/aes2550/custom.py

@@ -0,0 +1,41 @@
+#!/usr/bin/env python3
+
+import sys
+import traceback
+import gi
+
+gi.require_version('FPrint', '2.0')
+from gi.repository import FPrint, GLib
+
+# Exit with error on any exception, included those happening in async callbacks
+sys.excepthook = lambda *args: (traceback.print_exception(*args), sys.exit(1))
+
+if len(sys.argv) != 1:
+    print("This test does not accept arguments")
+    sys.exit(1)
+
+ctx = GLib.main_context_default()
+
+c = FPrint.Context()
+c.enumerate()
+devices = c.get_devices()
+
+d = devices[0]
+del devices
+
+d.open_sync()
+
+# We're testing that the device returns an error when only tapping the it.
+print("Please tap the fingerprint reader, but do not swipe your finger across it.")
+try:
+    d.capture_sync(True)
+except GLib.Error as error:
+    assert error.matches(FPrint.device_retry_quark(),
+                         FPrint.DeviceRetry.TOO_SHORT)
+else:
+    raise AssertionError("Capture did not raise FP_DEVICE_RETRY_TOO_SHORT")
+finally:
+    d.close_sync()
+
+del d
+del c