fix: show each platform row its own hash

tests/test_site_platform_hashes.py

@@ -0,0 +1,48 @@
+"""A platform page shows each row the hash its own declaration carries.
+
+The page joined verify's details to the platform YAML by file name alone,
+the last declaration winning: MiSTer declares boot.rom 23 times with 21
+distinct MD5s, and every boot.rom row showed the same one, so a user
+checking a dump against the page was told the wrong hash.
+"""
+
+from __future__ import annotations
+
+import sys
+import unittest
+from pathlib import Path
+
+REPO_ROOT = Path(__file__).resolve().parents[1]
+sys.path.insert(0, str(REPO_ROOT / "scripts"))
+
+from generate_site import _render_platform_systems  # noqa: E402
+
+A, B, C = "a" * 32, "b" * 32, "c" * 32
+
+
+class EachRowItsDeclaration(unittest.TestCase):
+    def test_same_name_in_two_systems_and_twice_in_one(self):
+        config_files = {
+            ("psx", "boot.rom"): [{"name": "boot.rom", "md5": A}],
+            ("saturn", "boot.rom"): [
+                {"name": "boot.rom", "md5": B},
+                {"name": "boot.rom", "md5": C},
+            ],
+        }
+        by_system = {
+            "psx": [{"name": "boot.rom", "status": "ok", "system": "psx"}],
+            "saturn": [
+                {"name": "boot.rom", "status": "ok", "system": "saturn"},
+                {"name": "boot.rom", "status": "ok", "system": "saturn"},
+            ],
+        }
+        text = "\n".join(_render_platform_systems(by_system, config_files, {}))
+        psx, saturn = text.split("saturn", 1)[0], text.split("saturn", 1)[1]
+        self.assertIn(A, psx)
+        self.assertNotIn(B, psx)
+        self.assertLess(saturn.index(B), saturn.index(C))
+        self.assertNotIn(A, saturn)
+
+
+if __name__ == "__main__":
+    unittest.main()