Deduplicate AndroidQF SMS analysis (#837)

tests/common/test_password.py

@@ -0,0 +1,28 @@
+# Mobile Verification Toolkit (MVT)
+# Copyright (c) 2026 The MVT Authors.
+# Use of this software is governed by the MVT License 1.1 that can be found at
+# https://license.mvt.re/1.1/
+
+from io import StringIO
+
+from mvt.common.password import _readline_with_asterisks
+
+
+def test_readline_with_asterisks():
+    output = StringIO()
+
+    password = _readline_with_asterisks(
+        output, StringIO("pass\x7fword\n"), "Enter backup password: "
+    )
+
+    assert password == "pasword"
+    assert output.getvalue() == "Enter backup password: ****\b \b****"
+
+
+def test_readline_with_asterisks_ignores_nul_and_handles_eof():
+    output = StringIO()
+
+    password = _readline_with_asterisks(output, StringIO("a\x00b\x04\x04"), "")
+
+    assert password == "ab"
+    assert output.getvalue() == "**"