fix: index the standalone layout for regions

GC/EUR/IPL.bin fell through to its bare name and the union of five regions, so a Batocera or standalone Dolphin pack never reduced it. The GameCube IPLs of four Dolphin-family profiles now name their system, as the MMJR profiles do.

emulators/dolphin.yml

@@ -38,6 +38,7 @@ files:
   - name: "IPL.bin"
     path: "dolphin-emu/Sys/GC/USA/IPL.bin"
     standalone_path: "GC/USA/IPL.bin"
+    system: nintendo-gamecube
     region: [north-america]
     size: 2097152
     required: false
@@ -48,6 +49,7 @@ files:
   - name: "IPL.bin"
     path: "dolphin-emu/Sys/GC/EUR/IPL.bin"
     standalone_path: "GC/EUR/IPL.bin"
+    system: nintendo-gamecube
     region: [europe, oceania]
     size: 2097152
     required: false
@@ -58,6 +60,7 @@ files:
   - name: "IPL.bin"
     path: "dolphin-emu/Sys/GC/JAP/IPL.bin"
     standalone_path: "GC/JAP/IPL.bin"
+    system: nintendo-gamecube
     region: [japan, south-korea]
     size: 2097152
     required: false

emulators/ishiiruka.yml

@@ -35,6 +35,7 @@ files:
   - name: "IPL.bin"
     path: "dolphin-emu/Sys/GC/USA/IPL.bin"
     standalone_path: "GC/USA/IPL.bin"
+    system: nintendo-gamecube
     region: [north-america]
     size: 2097152
     required: false
@@ -45,6 +46,7 @@ files:
   - name: "IPL.bin"
     path: "dolphin-emu/Sys/GC/EUR/IPL.bin"
     standalone_path: "GC/EUR/IPL.bin"
+    system: nintendo-gamecube
     region: [europe, oceania]
     size: 2097152
     required: false
@@ -55,6 +57,7 @@ files:
   - name: "IPL.bin"
     path: "dolphin-emu/Sys/GC/JAP/IPL.bin"
     standalone_path: "GC/JAP/IPL.bin"
+    system: nintendo-gamecube
     region: [japan, south-korea]
     size: 2097152
     required: false

emulators/primehack.yml

@@ -34,6 +34,7 @@ files:
   # Checked in User/GC/<region>/ then Sys/GC/<region>/
   - name: "IPL.bin"
     path: "GC/USA/IPL.bin"
+    system: nintendo-gamecube
     region: [north-america]
     size: 2097152
     required: false
@@ -43,6 +44,7 @@ files:
 
   - name: "IPL.bin"
     path: "GC/EUR/IPL.bin"
+    system: nintendo-gamecube
     region: [europe, oceania]
     size: 2097152
     required: false
@@ -52,6 +54,7 @@ files:
 
   - name: "IPL.bin"
     path: "GC/JAP/IPL.bin"
+    system: nintendo-gamecube
     region: [japan, south-korea]
     size: 2097152
     required: false

emulators/triforce.yml

@@ -195,6 +195,7 @@ files:
   - name: "IPL.bin"
     path: "GC/USA/IPL.bin"
     description: "GameCube NTSC-U boot ROM"
+    system: nintendo-gamecube
     region: [north-america]
     size: 2097152
     required: false
@@ -205,6 +206,7 @@ files:
   - name: "IPL.bin"
     path: "GC/EUR/IPL.bin"
     description: "GameCube PAL boot ROM"
+    system: nintendo-gamecube
     region: [europe, oceania]
     size: 2097152
     required: false
@@ -214,6 +216,7 @@ files:
   - name: "IPL.bin"
     path: "GC/JAP/IPL.bin"
     description: "GameCube NTSC-J boot ROM"
+    system: nintendo-gamecube
     region: [japan, south-korea]
     size: 2097152
     required: false

scripts/region.py

@@ -181,9 +181,11 @@ def build_region_index(profiles: dict) -> dict[str, dict]:
             path = f.get("path") or ""
             # Path-keyed so same-named entries stay separate (Dolphin declares
             # three IPL.bin), name-keyed so a candidate identified by name alone
-            # sees the union and is never dropped on ambiguity.
+            # sees the union and is never dropped on ambiguity. The standalone
+            # layout is a path of its own: GC/EUR/IPL.bin fell through to the
+            # bare name and its five-region union, and was never reduced.
             priority = f.get("priority")
-            for key in {path, name} - {""}:
+            for key in {path, f.get("standalone_path") or "", name} - {""}:
                 entry = index.setdefault(
                     key,
                     {"regions": set(), "has_untagged": False, "emulators": [],

scripts/slot.py

@@ -60,7 +60,8 @@ def build_slot_index(profiles: dict) -> dict[str, dict]:
                 continue
             name = f.get("name", "")
             path = f.get("path") or ""
-            for key in {path, name} - {""}:
+            # Keyed by the standalone layout too, as build_region_index is.
+            for key in {path, f.get("standalone_path") or "", name} - {""}:
                 entry = index.setdefault(
                     key,
                     {"rank": None, "conflict": False, "regions": set(),

tests/test_region.py

@@ -246,6 +246,25 @@ class TestRegionIndex(unittest.TestCase):
         self.assertIn("x.bin", str(ctx.exception))
 
 
+class TestStandaloneLayoutIsIndexed(unittest.TestCase):
+    """GC/EUR/IPL.bin, Dolphin's standalone path, was looked up by its bare
+    name and got the union of five regions: never reduced in a Batocera
+    pack nor in --emulator dolphin --standalone."""
+
+    def test_the_standalone_path_carries_its_own_regions(self):
+        import slot
+
+        profiles = {"dolphin": {"files": [
+            {"name": "IPL.bin", "path": "dolphin-emu/Sys/GC/USA/IPL.bin",
+             "standalone_path": "GC/USA/IPL.bin", "region": ["north-america"]},
+            {"name": "IPL.bin", "path": "dolphin-emu/Sys/GC/EUR/IPL.bin",
+             "standalone_path": "GC/EUR/IPL.bin", "region": ["europe"]},
+        ]}}
+        index = region.build_region_index(profiles)
+        self.assertEqual(region.lookup_regions(index, "GC/EUR/IPL.bin", "IPL.bin"), {"europe"})
+        self.assertIn("GC/EUR/IPL.bin", slot.build_slot_index(profiles))
+
+
 class TestResolveRegionDrops(unittest.TestCase):
     def setUp(self):
         self.index = region.build_region_index(