[verified] Document bounded Discovery checker preparation

harness/tests/spec/test_priority_review_contracts.py

@@ -110,6 +110,21 @@ class PriorityReviewContracts(unittest.TestCase):
         self.assertLess(step.index('비정본·변경된 readback helper 호출 계약'),
                         step.index('Native review create를'))
 
+    def test_discovery_checker_documentation_contract_preserves_bytes_and_bounded_transformations(self):
+        text = DISCOVERY.read_text()
+        heading = '### 임시·변경된 Discovery checker 준비'
+        self.assertIn(heading, text, 'bounded Discovery checker preparation guidance is missing')
+        section = text.split(heading, 1)[1].split('\n## ', 1)[0]
+        for rule in ('임시·변경된', 'LF/CRLF', 'splitlines', '원본 bytes',
+                     'payload', 'hash', 'flags=', 'section·paragraph',
+                     'OQ ID', '정확 문구', 'prefix', '일괄 면제하지',
+                     'replay', '외부 write 없이', '사용자 선택',
+                     '공통 semantic validator', '부분 완료', 'synthetic'):
+            with self.subTest(rule=rule):
+                self.assertIn(rule, section)
+        step = text.split('11. trusted workflow directory', 1)[1].split('\n12.', 1)[0]
+        self.assertIn('임시·변경된 Discovery checker 준비', step)
+
     def test_local_links_resolve_and_procedures_reference_new_rules(self):
         for path in (DISCOVERY, IMPLEMENTATION, README):
             text = path.read_text()
@@ -120,6 +135,61 @@ class PriorityReviewContracts(unittest.TestCase):
         self.assertIn('11. 문서 검토 입력과 구조·의미 분리 절차', IMPLEMENTATION.read_text())
 
 
+class SyntheticDiscoveryCheckerControls(unittest.TestCase):
+    """Small local primitive examples, not a shared Discovery validator."""
+
+    def test_synthetic_logical_headings_accept_crlf_without_rewriting_bytes(self):
+        import hashlib
+        lf = b'## Scope\nbody\n## Questions\nnone\n'
+        crlf = lf.replace(b'\n', b'\r\n')
+        original_digest = hashlib.sha256(crlf).digest()
+        self.assertIsNone(re.search(r'^## Scope$', crlf.decode(), flags=re.MULTILINE))
+        expected = ['## Scope', '## Questions']
+        for raw in (lf, crlf):
+            headings = [line for line in raw.decode().splitlines() if line.startswith('## ')]
+            self.assertEqual(headings, expected)
+        for malformed in (lf.replace(b'## Scope', b'## Scopes'),
+                          lf + b'## Scope\n', lf.replace(b'## Questions\n', b'')):
+            headings = [line for line in malformed.decode().splitlines() if line.startswith('## ')]
+            self.assertNotEqual(headings, expected)
+        self.assertEqual(hashlib.sha256(crlf).digest(), original_digest)
+        self.assertEqual(crlf, b'## Scope\r\nbody\r\n## Questions\r\nnone\r\n')
+
+    def test_synthetic_exact_paragraph_exception_does_not_hide_other_oq_residue(self):
+        old = 'OQ-1: legacy introduction'
+        replacement = old + '; explicit approved reselection'
+        paragraphs = {'decision': replacement, 'question': 'OQ-2: unrelated question'}
+        self.assertIn(old, paragraphs['decision'])  # Naive global substring false positive.
+        self.assertEqual(paragraphs['decision'], replacement)
+        residue = {key: value for key, value in paragraphs.items()
+                   if old in value and not (key == 'decision' and value == replacement)}
+        self.assertEqual(residue, {})
+        paragraphs['question'] = old + '; unresolved reference in OQ-2'
+        residue = {key: value for key, value in paragraphs.items()
+                   if old in value and not (key == 'decision' and value == replacement)}
+        self.assertEqual(set(residue), {'question'})
+        self.assertEqual(paragraphs['decision'], replacement)
+
+    def test_synthetic_self_containing_exact_replacement_replays_without_duplication(self):
+        old = b'Legacy introduction'
+        replacement = old + b'; approved detail'
+        naive_replay = replacement.replace(old, replacement)
+        self.assertNotEqual(naive_replay, replacement)
+        # Approved exact paragraph fixture only; no general normalization policy.
+        def fixture_transform(paragraph):
+            if paragraph == replacement:
+                return paragraph
+            if paragraph == old:
+                return replacement
+            raise ValueError('ambiguous paragraph fixture')
+
+        first = fixture_transform(old)
+        self.assertEqual(first, replacement)
+        self.assertEqual(fixture_transform(first), first)
+        with self.assertRaisesRegex(ValueError, 'ambiguous paragraph fixture'):
+            fixture_transform(old + b'; unrelated edit')
+
+
 class SyntheticReadbackInvocationTests(unittest.TestCase):
     """Local Python binding/collector controls, not a production pre-create gate."""