fix: pair a bare truth name by name, not suffix

scripts/exporter/baseline.py

@@ -325,8 +325,13 @@ def build_native_model(
             def by_destination(candidate: NativeFile, t_dest: str = t_dest) -> bool:
                 # Dolphin writes dolphin-emu/Sys/GC/USA/IPL.bin for the truth's
                 # GC/USA/IPL.bin: a destination ending in the path is the file.
+                # A bare name is no path: dc/boot.bin ends in /boot.bin, and
+                # fbneo's 480-byte boot.bin is not that 2 MB Dreamcast BIOS.
+                # Names go through by_name and its size guard.
                 theirs = _match_key(candidate.platform or {})[0]
-                return bool(t_dest) and (theirs == t_dest or theirs.endswith("/" + t_dest))
+                if not t_dest:
+                    return False
+                return theirs == t_dest or ("/" in t_dest and theirs.endswith("/" + t_dest))
 
             def by_name(
                 candidate: NativeFile,

tests/test_exporters.py

@@ -120,6 +120,22 @@ def model(truth: dict = TRUTH, scraped: dict | None = SCRAPED):
 class Reconciliation(unittest.TestCase):
     """The platform's file corrected, not replaced by ours."""
 
+    def test_a_bare_truth_name_is_not_a_path_suffix(self):
+        """fbneo's boot.bin has no path; libretro's dc/boot.bin ends in
+        /boot.bin. The suffix paired them past the size guard and wrote the
+        480-byte file's size and hashes over the 2 MB Dreamcast BIOS."""
+        truth = {"systems": {"sega-dreamcast": {"files": [
+            {"name": "boot.bin", "size": 480, "crc32": "f0774fc2"}]}}}
+        scraped = {"systems": {"sega-dreamcast": {"native_id": "dc", "files": [
+            {"name": "boot.bin", "destination": "dc/boot.bin", "native_system": "dc",
+             "size": 2097152, "crc32": "89f2b1a1"}]}}}
+        systems, report = build_native_model(truth, scraped)
+        platform_entry = next(
+            fe for fe in systems["dc"].files if fe.destination == "dc/boot.bin"
+        )
+        self.assertIsNone(platform_entry.truth)
+        self.assertEqual(report.hashes_corrected, [])
+
     def test_a_file_the_truth_says_nothing_about_is_kept(self):
         systems, _ = model()
         names = {fe.name for fe in systems["psx"].files}