fix: write emudeck corrections, count only what lands

scripts/exporter/emudeck_exporter.py

@@ -90,8 +90,27 @@ class Exporter(BaseExporter):
     def states(self, fe: NativeFile, field_name: str) -> bool:
         if field_name in fe.filled:
             return False
+        if field_name == "md5" and fe.native_system in self._refused_systems():
+            # The array was left as EmuDeck wrote it: nothing was corrected.
+            return False
         return super().states(fe, field_name)
 
+    def _refused_systems(self) -> set[str]:
+        withdrawn = getattr(self, "_withdrawn", {})
+        return {FUNCTION_HASH_MAP[name] for name in withdrawn if name in FUNCTION_HASH_MAP}
+
+    @staticmethod
+    def _corrected_away(systems: dict[str, NativeSystem], system_id: str) -> set[str]:
+        """The platform md5 values a correction of ours replaces."""
+        return {
+            value
+            for system in systems.values()
+            if system.native_id == system_id
+            for fe in system.files
+            if "md5" in fe.corrections
+            for value in _hash_values(fe.platform or {}, "md5")
+        }
+
     @classmethod
     def _md5s(cls, systems: dict[str, NativeSystem], system_id: str) -> list[str]:
         """Every MD5 the system accepts, in a stable order, deduplicated."""
@@ -151,7 +170,9 @@ class Exporter(BaseExporter):
                 # and our model does not was deleted: a user whose dump matched
                 # it would stop passing the check. A rewrite that withdraws one
                 # is refused and reported instead.
-                withdrawn = theirs - set(md5s)
+                # A correction replaces the value it corrects, which is not a
+                # withdrawal; any other value missing from ours would be.
+                withdrawn = theirs - set(md5s) - self._corrected_away(systems, system_id)
                 if withdrawn:
                     self._withdrawn.setdefault(name, set()).update(withdrawn)
                 elif set(md5s) != theirs:
@@ -180,7 +201,8 @@ class Exporter(BaseExporter):
                 issues.append(f"check absent from the output: {name}")
                 continue
             md5s = self._md5s(systems, system_id)
-            if not md5s:
+            if not md5s or name in getattr(self, "_withdrawn", {}):
+                # A refused rewrite keeps EmuDeck's own array, by design.
                 continue
             body = next(
                 content[start:end]

tests/test_export_counts.py

@@ -123,6 +123,49 @@ class HashesTheFormatCannotHold(unittest.TestCase):
         self.assertFalse(EmuDeck().states(unhashed, "md5"))
 
 
+class EmuDeckWritesItsCorrections(unittest.TestCase):
+    """A correction replaced nothing: every withdrawal was refused, the run
+    counted the correction anyway and validate failed on it."""
+
+    SCRIPT = "checkPS1BIOS(){\n  local hashes=(%s)\n}\n"
+
+    def _systems(self, corrected: NativeFile, other: NativeFile) -> dict:
+        from scraper.emudeck_scraper import FUNCTION_HASH_MAP
+
+        system_id = FUNCTION_HASH_MAP["checkPS1BIOS"]
+        corrected.native_system = other.native_system = system_id
+        return {system_id: NativeSystem(system_id, files=[corrected, other])}
+
+    def test_a_correction_replaces_its_value(self):
+        corrected = NativeFile("scph5501.bin", "scph5501.bin", "psx",
+                               platform={"md5": A}, truth={"md5": B}, corrections=["md5"])
+        other = NativeFile("scph1001.bin", "scph1001.bin", "psx", platform={"md5": C})
+        systems = self._systems(corrected, other)
+        exporter = EmuDeck()
+        produced = exporter.render(systems, None, {"checkBIOS.sh": self.SCRIPT % f"{A} {C}"})
+        text = produced["checkBIOS.sh"]
+        self.assertIn(B, text)
+        self.assertNotIn(A, text)
+        self.assertTrue(exporter.states(corrected, "md5"))
+        self.assertEqual(
+            [i for i in exporter.validate(systems, produced) if "checkPS1BIOS" in i], []
+        )
+
+    def test_a_withdrawal_is_refused_and_not_counted(self):
+        corrected = NativeFile("scph5501.bin", "scph5501.bin", "psx",
+                               platform={"md5": A}, truth={"md5": B}, corrections=["md5"])
+        other = NativeFile("scph1001.bin", "scph1001.bin", "psx", platform={"md5": C})
+        systems = self._systems(corrected, other)
+        exporter = EmuDeck()
+        d = "d" * 32
+        produced = exporter.render(systems, None, {"checkBIOS.sh": self.SCRIPT % f"{A} {C} {d}"})
+        self.assertIn(d, produced["checkBIOS.sh"])
+        self.assertFalse(exporter.states(corrected, "md5"))
+        self.assertEqual(
+            [i for i in exporter.validate(systems, produced) if "checkPS1BIOS" in i], []
+        )
+
+
 class ModelKeepsOneFileOneEntry(unittest.TestCase):
     def test_size_describes_the_hash_written(self):
         fe = NativeFile("boot.bin", "dc/boot.bin", "dc",