feat: record the commit a branch scrape read

Six platforms are read from a branch: System.dat, batocera-systems.json, checkBIOS.sh, the MiSTer BiosDB, the RetroPie scriptmodules and the RetroDECK component manifests. Their YAML named the branch, so the native export patched whatever the branch had become since the scrape. Each scraper now resolves the branch head once, reads every file at that commit and writes it into source. The export follows a recorded tarball and a recorded tree as it already followed a raw file URL.

scripts/scraper/retrobat_scraper.py

@@ -16,6 +16,7 @@ try:
     from .base_scraper import (
         BaseScraper,
         BiosRequirement,
+        fetch_branch_head,
         fetch_github_latest_version,
         requirement_entry,
     )
@@ -24,6 +25,7 @@ except ImportError:
     from base_scraper import (
         BaseScraper,
         BiosRequirement,
+        fetch_branch_head,
         fetch_github_latest_version,
         requirement_entry,
     )
@@ -31,9 +33,10 @@ except ImportError:
 
 PLATFORM_NAME = "retrobat"
 
+LAUNCHER_REPO = "RetroBat-Official/emulatorlauncher"
 SOURCE_URL = (
     "https://raw.githubusercontent.com/RetroBat-Official/emulatorlauncher/"
-    "master/batocera-systems/Resources/batocera-systems.json"
+    "{rev}/batocera-systems/Resources/batocera-systems.json"
 )
 
 GITHUB_REPO = "RetroBat-Official/retrobat"
@@ -103,7 +106,10 @@ SYSTEM_SLUG_MAP = {
 class Scraper(BaseScraper):
     """Scraper for RetroBat batocera-systems.json."""
 
-    def __init__(self, url: str = SOURCE_URL) -> None:
+    def __init__(self, url: str | None = None) -> None:
+        # batocera-systems.json is read from master: the commit read is recorded.
+        if url is None:
+            url = SOURCE_URL.format(rev=fetch_branch_head(LAUNCHER_REPO, "master"))
         super().__init__(url=url)
         self._parsed: dict | None = None
 
@@ -234,7 +240,7 @@ class Scraper(BaseScraper):
             "platform": "RetroBat",
             "version": version,
             "homepage": "https://www.retrobat.org",
-            "source": SOURCE_URL,
+            "source": self.url,
             "base_destination": "bios",
             "hash_type": "md5",
             "verification_mode": "md5",