fix: link systems to the folder of their files

tests/test_site_system_links.py

@@ -0,0 +1,60 @@
+"""A platform system links to the page of the folder its files live in.
+
+The site mapped each system by the bare name of its first file, the last
+console written winning: MiSTer's boot.rom sits under a dozen consoles, so
+wonderswan and tiger-game-com linked to VideoBrain, ngpc and tandy-coco to
+TI-99. Reads the repository: skips when the database is absent.
+"""
+
+from __future__ import annotations
+
+import os
+import sys
+import unittest
+from pathlib import Path
+
+REPO_ROOT = Path(__file__).resolve().parents[1]
+sys.path.insert(0, str(REPO_ROOT / "scripts"))
+
+import generate_site as gs  # noqa: E402
+
+
+class LinksFollowContent(unittest.TestCase):
+    def test_an_ambiguous_name_places_nothing(self):
+        names = {"boot.rom": {("VideoBrain", "VideoBrain"), ("Bandai", "WonderSwan")}}
+        files = [{"name": "boot.rom", "sha1": "0" * 40}]
+        self.assertIsNone(gs._system_folder(files, {"files": {}, "indexes": {}}, names))
+        names["only.rom"] = {("Bandai", "WonderSwan")}
+        files.append({"name": "only.rom"})
+        self.assertEqual(
+            gs._system_folder(files, {"files": {}, "indexes": {}}, names),
+            ("Bandai", "WonderSwan"),
+        )
+
+    def test_mister_systems(self):
+        if not (REPO_ROOT / "database.json").exists():
+            self.skipTest("database.json is not built")
+        previous = os.getcwd()
+        os.chdir(REPO_ROOT)
+        self.addCleanup(os.chdir, previous)
+        from common import load_database, load_platform_config
+
+        db = load_database("database.json")
+        config = load_platform_config("misterfpga")
+        names: dict = {}
+        for mfr, consoles in gs._group_by_manufacturer(db).items():
+            for console, entries in consoles.items():
+                for entry in entries:
+                    names.setdefault(entry["name"], set()).add((mfr, console))
+        expected = {"wonderswan": "WonderSwan", "ngpc": "Neo Geo Pocket"}
+        for sys_id, console in expected.items():
+            system = config["systems"].get(sys_id)
+            if system is None:
+                continue
+            with self.subTest(system=sys_id):
+                place = gs._system_folder(system.get("files", []), db, names)
+                self.assertEqual(place and place[1], console)
+
+
+if __name__ == "__main__":
+    unittest.main()