fix: keep cross-named aliases inside their profile

tests/test_db_aliases.py

@@ -111,5 +111,29 @@ class AcceptedRevisionLists(unittest.TestCase):
         for sha in ("s1", "s2"):
             self.assertEqual([a["name"] for a in aliases.get(sha, [])], ["MT32_CONTROL.ROM"])
 
+class CrossNamingStaysInItsProfile(unittest.TestCase):
+    def test_an_alias_naming_a_sibling_entry_is_not_indexed(self):
+        """dosbox-x aliases MT32_CONTROL.ROM and CM32L_CONTROL.ROM to each other."""
+        import generate_db
+
+        with tempfile.TemporaryDirectory(dir=REPO_ROOT / "tmp") as tmp:
+            previous = os.getcwd()
+            os.chdir(tmp)
+            try:
+                Path("emulators").mkdir()
+                Path("emulators/d.yml").write_text(
+                    'files:\n'
+                    '  - name: "MT32_CONTROL.ROM"\n    sha1: "mt"\n    aliases: ["CM32L_CONTROL.ROM"]\n'
+                    '  - name: "CM32L_CONTROL.ROM"\n    sha1: "cm"\n    aliases: ["MT32_CONTROL.ROM"]\n'
+                )
+                aliases = generate_db._collect_all_aliases({
+                    "mt": {"name": "mt32_control.rom", "path": "a", "md5": "m1"},
+                    "cm": {"name": "cm32l_control.rom", "path": "b", "md5": "m2"},
+                })
+            finally:
+                os.chdir(previous)
+        self.assertEqual([a["name"] for a in aliases["mt"]], ["MT32_CONTROL.ROM"])
+        self.assertEqual([a["name"] for a in aliases["cm"]], ["CM32L_CONTROL.ROM"])
+
 if __name__ == "__main__":
     unittest.main()

tests/test_name_tiebreak.py

@@ -0,0 +1,36 @@
+"""Same-named candidates are ordered by the size the entry declares.
+
+ScummVM declares MT32_PCM.ROM at 524288 bytes; the name step took the 1 MB
+CM-32L PCM ROM that sorted first. Ordering rejects nothing, so a size
+without `validation: [size]` keeps its informative status.
+"""
+
+from __future__ import annotations
+
+import sys
+import tempfile
+import unittest
+from pathlib import Path
+
+REPO_ROOT = Path(__file__).resolve().parents[1]
+sys.path.insert(0, str(REPO_ROOT / "scripts"))
+
+from common import _by_affinity  # noqa: E402
+
+
+class DeclaredSizeOrders(unittest.TestCase):
+    def test_the_fitting_size_comes_first(self):
+        with tempfile.TemporaryDirectory(dir=REPO_ROOT / "tmp") as tmp:
+            big = Path(tmp) / "a" / "pcm.rom"
+            small = Path(tmp) / "b" / "pcm.rom"
+            for path, size in ((big, 1024), (small, 512)):
+                path.parent.mkdir()
+                path.write_bytes(b"x" * size)
+            ordered = _by_affinity([str(big), str(small)], {"size": 512}, "")
+            self.assertEqual(ordered[0], str(small))
+            kept = _by_affinity([str(big), str(small)], {}, "")
+            self.assertEqual(kept, [str(big), str(small)])
+
+
+if __name__ == "__main__":
+    unittest.main()