USB external import, and filter chips on health-dot cards

tests/test_plugins/test_usb_import_pairing.py

@@ -0,0 +1,99 @@
+"""Folding an external check-in/out LOG into self-hosted checkout PAIRS.
+
+The external cmmc_usb database records one row per action; the self-hosted
+usbcheckouts table records one row per checkout, carrying both times. The
+import has to convert between them, and the interesting cases are all the ways
+a real log is untidy after years of use: a drive still out, a return nobody
+has a matching issue for, two issues in a row.
+
+The rule these tests pin down is that NOTHING is invented and NOTHING vanishes
+silently. An unclosed checkout stays unclosed; anything that cannot be paired
+is reported. A quieter import that guessed the missing halves would produce a
+tidier database and a false audit history, which for removable-media records is
+the worst of the available outcomes.
+"""
+
+from plugins.usb.cli import _pair, _tri
+
+
+def _row(action, when, badge='B1'):
+    return {'action': action, 'timestamp': when, 'badge_number': badge}
+
+
+def test_a_clean_out_and_in_becomes_one_closed_checkout():
+    problems = []
+    pairs = _pair([_row('check-out', 1), _row('check-in', 2)], problems, 'DEV1')
+
+    assert len(pairs) == 1
+    out, back = pairs[0]
+    assert out['timestamp'] == 1
+    assert back['timestamp'] == 2
+    assert problems == []
+
+
+def test_a_drive_still_out_stays_open_and_is_not_reported_as_a_problem():
+    # This is the normal state of any drive currently issued to somebody, not
+    # a data fault, so it must not appear in the problem list.
+    problems = []
+    pairs = _pair([_row('check-out', 1)], problems, 'DEV1')
+
+    assert len(pairs) == 1
+    out, back = pairs[0]
+    assert back is None
+    assert problems == []
+
+
+def test_a_return_with_no_matching_issue_is_skipped_and_reported():
+    problems = []
+    pairs = _pair([_row('check-in', 5)], problems, 'DEV1')
+
+    assert pairs == []
+    assert len(problems) == 1
+    assert 'no matching check-out' in problems[0]
+    assert 'DEV1' in problems[0]
+
+
+def test_two_issues_in_a_row_leave_the_first_open_rather_than_inventing_a_return():
+    problems = []
+    pairs = _pair([_row('check-out', 1, 'ALICE'),
+                   _row('check-out', 2, 'BOB'),
+                   _row('check-in', 3, 'BOB')], problems, 'DEV1')
+
+    assert len(pairs) == 2
+    first, second = pairs
+    assert first[0]['badge_number'] == 'ALICE'
+    assert first[1] is None, 'the first checkout must not be given a return time'
+    assert second[0]['badge_number'] == 'BOB'
+    assert second[1]['timestamp'] == 3
+    assert len(problems) == 1
+    assert 'still out' in problems[0]
+
+
+def test_an_unrecognised_action_is_skipped_and_reported():
+    problems = []
+    pairs = _pair([_row('destroyed', 1)], problems, 'DEV1')
+
+    assert pairs == []
+    assert len(problems) == 1
+    assert 'unrecognised action' in problems[0]
+
+
+def test_action_spelling_variants_are_accepted():
+    # Years of a hand-maintained log produce more than one spelling.
+    for out_word, in_word in (('check-out', 'check-in'),
+                              ('checkout', 'checkin'),
+                              ('out', 'in'),
+                              ('CHECK_OUT', 'RETURN')):
+        problems = []
+        pairs = _pair([_row(out_word, 1), _row(in_word, 2)], problems, 'DEV1')
+        assert len(pairs) == 1, out_word
+        assert pairs[0][1] is not None, out_word
+        assert problems == [], out_word
+
+
+def test_unrecorded_flags_stay_unknown_rather_than_becoming_false():
+    # NULL in the source means nobody wrote it down. False would assert that
+    # the drive was checked and failed, which is a different claim entirely.
+    assert _tri(None) is None
+    assert _tri(0) is False
+    assert _tri(1) is True