Harden CI digest parsing and failure cleanup

tests/run-digest-tests.py

@@ -0,0 +1,34 @@
+"""Run in an x64 VS developer shell with Windows SDK and Python 3 installed.
+
+Extracts the actual production functions without changing their bodies, replacing
+only kernel dependencies with the test harness. No driver is loaded. This tests
+parsing, hashing and cleanup, not real CI policy or kernel I/O synchronization.
+"""
+import argparse
+from pathlib import Path
+import subprocess
+import tempfile
+
+parser = argparse.ArgumentParser()
+parser.add_argument('--source-root', type=Path, default=Path(__file__).resolve().parents[1])
+parser.add_argument('--digest-source', type=Path)
+args = parser.parse_args()
+root = args.source_root
+digest = (args.digest_source or root / 'src/Domito.CodeIntegrity.cpp').read_text(encoding='utf-8-sig')
+digest = digest.replace('#include "Domito.Internal.h"', '').replace('#include "Domito.MinCrypt.h"', '')
+common = (root / 'src/Domito.cpp').read_text(encoding='utf-8-sig')
+start = common.rfind('_Success_', 0, common.index('DomitoMemorySearchPattern('))
+end = common.index('_Success_', common.index('DomitoMemorySearchPattern('))
+search = common[start:end]
+public = (root / 'include/Domito.h').read_text(encoding='utf-8-sig')
+start = public.index('#if !defined(CALG_SHA1)')
+end = public.index('/*', public.index('DOMITO_CALG_TO_BCRYPT_ALGORITHM('))
+algorithm = public[start:end]
+with tempfile.TemporaryDirectory(prefix='domito-digest-tests-') as temp:
+    build = Path(temp)
+    (build / 'digest-under-test.inc').write_text(algorithm + '\n' + search + '\n' + digest, encoding='utf-8')
+    test_source = Path(__file__).with_name('digest-tests.cpp')
+    subprocess.run(['cl', '/nologo', '/EHsc', '/W4', '/WX', '/std:c++17',
+                    '/I' + str(build), str(test_source), '/Fe' + str(build/'digest-tests.exe'),
+                    '/Fo' + str(build/'digest-tests.obj'), '/link', 'bcrypt.lib'], cwd=build, check=True)
+    subprocess.run([str(build/'digest-tests.exe')], cwd=build, check=True)