feat: hash-based matching for cross-reference

expand_platform_declared_names resolves platform file MD5s
through the database to recover canonical names and aliases,
eliminating false positive undeclared files when a platform
renames a file (e.g. Batocera ROM1 vs gsplus ROM).

scripts/common.py

@@ -915,6 +915,39 @@ def filter_systems_by_target(
     return filtered
 
 
+def expand_platform_declared_names(config: dict, db: dict) -> set[str]:
+    """Build set of file names declared by a platform config.
+
+    Enriches the set with canonical names and aliases from the database
+    by resolving each platform file's MD5 through by_md5.  This handles
+    cases where a platform declares a file under a different name than
+    the emulator profile (e.g. Batocera ROM1 vs gsplus ROM).
+    """
+    declared: set[str] = set()
+    by_md5 = db.get("indexes", {}).get("by_md5", {})
+    files_db = db.get("files", {})
+    for system in config.get("systems", {}).values():
+        for fe in system.get("files", []):
+            name = fe.get("name", "")
+            if name:
+                declared.add(name)
+            md5 = fe.get("md5", "")
+            if not md5:
+                continue
+            # Skip multi-hash and zippedFile entries (inner ROM MD5, not file MD5)
+            if "," in md5 or fe.get("zippedFile"):
+                continue
+            sha1 = by_md5.get(md5.lower())
+            if not sha1:
+                continue
+            entry = files_db.get(sha1, {})
+            db_name = entry.get("name", "")
+            if db_name:
+                declared.add(db_name)
+            for alias in entry.get("aliases", []):
+                declared.add(alias)
+    return declared
+
 
 # Validation and mode filtering -extracted to validation.py for SoC.
 # Re-exported below for backward compatibility.

scripts/generate_pack.py

@@ -28,7 +28,7 @@ sys.path.insert(0, os.path.dirname(__file__))
 from common import (
     MANUFACTURER_PREFIXES,
     build_target_cores_cache, build_zip_contents_index, check_inside_zip,
-    compute_hashes, fetch_large_file, group_identical_platforms,
+    compute_hashes, expand_platform_declared_names, fetch_large_file, group_identical_platforms,
     list_emulator_profiles, list_platform_system_ids, list_registered_platforms,
     filter_systems_by_target, list_system_ids, load_database,
     load_data_dir_registry, load_emulator_profiles, load_platform_config,
@@ -371,12 +371,8 @@ def _collect_emulator_extras(
     by_path_suffix = db.get("indexes", {}).get("by_path_suffix", {})
 
     # Build set of filenames already covered (platform baseline + first pass extras)
-    covered_names: set[str] = set()
-    for sys_id, system in config.get("systems", {}).items():
-        for fe in system.get("files", []):
-            n = fe.get("name", "")
-            if n:
-                covered_names.add(n)
+    # Enriched with canonical names from DB via MD5 (handles platform renaming)
+    covered_names = expand_platform_declared_names(config, db)
     for e in extras:
         covered_names.add(e["name"])
 

scripts/verify.py

@@ -31,10 +31,11 @@ from pathlib import Path
 sys.path.insert(0, os.path.dirname(__file__))
 from common import (
     build_target_cores_cache, build_zip_contents_index, check_inside_zip,
-    compute_hashes, filter_systems_by_target, group_identical_platforms,
-    list_emulator_profiles, list_system_ids, load_data_dir_registry,
-    load_emulator_profiles, load_platform_config, md5sum, md5_composite,
-    require_yaml, resolve_local_file, resolve_platform_cores,
+    compute_hashes, expand_platform_declared_names, filter_systems_by_target,
+    group_identical_platforms, list_emulator_profiles, list_system_ids,
+    load_data_dir_registry, load_emulator_profiles, load_platform_config,
+    md5sum, md5_composite, require_yaml, resolve_local_file,
+    resolve_platform_cores,
 )
 
 yaml = require_yaml()
@@ -261,13 +262,9 @@ def find_undeclared_files(
     data_names: set[str] | None = None,
 ) -> list[dict]:
     """Find files needed by cores but not declared in platform config."""
-    # Collect all filenames declared by this platform
-    declared_names: set[str] = set()
-    for sys_id, system in config.get("systems", {}).items():
-        for fe in system.get("files", []):
-            name = fe.get("name", "")
-            if name:
-                declared_names.add(name)
+    # Collect all filenames declared by this platform, enriched with
+    # canonical names from DB via MD5 (handles platform renaming)
+    declared_names = expand_platform_declared_names(config, db)
 
     # Collect data_directory refs
     declared_dd: set[str] = set()