chore: merge round 4 fixes (links)

Both branches extracted RetroBat's Flycast BiosPath: value_folders
already produces the record, so the dedicated extractor is dropped and
its test reads the generic one.

scripts/scraper/batocera_launchers.py

@@ -647,6 +647,46 @@ def gsplus(cg: Configgen) -> list[Launcher]:
     )]
 
 
+# Generators that hand a directory of /userdata/bios to the emulator through
+# its environment, with the module holding their path constants.
+ENVIRONMENT_GENERATORS = (("flycast.flycastGenerator", "flycast/flycastPaths.py"),)
+
+
+def environment_directories(cg: Configgen) -> list[Launcher]:
+    """Command(..., env={KEY: <path under BIOS>}) in the generator."""
+    launchers = []
+    for module, paths_module in ENVIRONMENT_GENERATORS:
+        src = cg.generator(module)
+        constants = dict(cg.paths)
+        for node in cg.source(f"{GENERATORS}/{paths_module}").tree.body:
+            name = _assigned_name(node)
+            value = _path_value(getattr(node, "value", None), constants)
+            if name is not None and value is not None:
+                constants[name] = value
+        prefix = cg.bios.rstrip("/")
+        found = [
+            (key.value, value, key)
+            for call in _calls(src.tree, attr="Command")
+            for keyword in call.keywords
+            if keyword.arg == "env" and isinstance(keyword.value, ast.Dict)
+            for key, item in zip(keyword.value.keys, keyword.value.values)
+            if isinstance(key, ast.Constant)
+            and (value := _path_value(item, constants)) is not None
+            and (value == prefix or value.startswith(prefix + "/"))
+        ]
+        if not found:
+            src.fail("the command environment names no /userdata/bios directory")
+        launchers.extend(
+            Launcher(
+                emulator=cg.emulator(module), build="standalone", kind="passes_path",
+                names=[], search_dir=value, passes_to=f"environment {key}",
+                source_ref=src.ref([(node.lineno, node.end_lineno)]),
+            )
+            for key, value, node in found
+        )
+    return launchers
+
+
 # libretro core options whose value names the BIOS file the core opens.
 FILE_OPTIONS = (("_o2em_options", "o2em_bios"), ("_neocd_options", "neocd_bios"))
 
@@ -701,7 +741,7 @@ def core_file_options(cg: Configgen) -> list[Launcher]:
 
 EXTRACTORS: tuple[Callable[[Configgen], list[Launcher]], ...] = (
     duckstation, duckstation_legacy, hatari, xemu, melonds, mupen64plus,
-    x16emu, gsplus, core_file_options,
+    x16emu, gsplus, environment_directories, core_file_options,
 )
 
 

scripts/scraper/emudeck_scraper.py

@@ -231,6 +231,25 @@ def launcher_revision(url: str) -> str:
     return found.group(1)
 
 
+RETROARCH_SCRIPT = "functions/EmuScripts/emuDeckRetroArch.sh"
+
+
+def installed_libretro_cores(script: str) -> list[str]:
+    """The cores RetroArch_installCores downloads, without the _libretro suffix."""
+    body = re.search(r"RetroArch_installCores\(\)\s*\{(.*?)\n\}", script, re.S)
+    array = re.search(r"RAcores=\((.*?)\)", body.group(1), re.S) if body else None
+    if array is None:
+        raise RuntimeError(f"{RETROARCH_SCRIPT}: no RAcores list in RetroArch_installCores")
+    cores = [
+        word.removesuffix("_libretro")
+        for word in array.group(1).replace("\\", " ").split()
+        if word.endswith("_libretro")
+    ]
+    if not cores:
+        raise RuntimeError(f"{RETROARCH_SCRIPT}: RAcores names no core")
+    return cores
+
+
 class Scraper(BaseScraper):
     """Scraper for EmuDeck checkBIOS.sh and CSV cheat sheets."""
 
@@ -451,6 +470,9 @@ class Scraper(BaseScraper):
         version = fetch_github_latest_version("dragoonDorise/EmuDeck")
 
         cores = self._fetch_installed_emulators()
+        standalone = [core for core in cores if core != "retroarch"]
+        tree = RepoTree.github(EMUDECK_REPO, launcher_revision(self.checkbios_url))
+        libretro = set(installed_libretro_cores(tree.read(RETROARCH_SCRIPT)))
 
         return {
             "platform": "EmuDeck",
@@ -469,12 +491,14 @@ class Scraper(BaseScraper):
             # Dolphin, Cemu, xemu, ARMSX2 and Supermodel ran with the libretro
             # layout and lost their standalone-only files. A profile with no
             # standalone build keeps its layout (runs_standalone).
-            "standalone_cores": [core for core in cores if core != "retroarch"],
+            "standalone_cores": standalone,
+            # RetroArch_installCores downloads a libretro build of some of
+            # them (flycast_libretro reads system/dc/ beside the standalone
+            # Flycast's flycast/bios/): both layouts are packed.
+            "dual_mode_cores": [core for core in standalone if core in libretro],
             "systems": systems,
             # Read at the commit checkBIOS.sh comes from.
-            "launchers": extract_launchers(
-                RepoTree.github(EMUDECK_REPO, launcher_revision(self.checkbios_url))
-            ),
+            "launchers": extract_launchers(tree),
         }
 
     def _fetch_installed_emulators(self) -> list[str]:

scripts/scraper/rocknix_launchers.py

@@ -612,6 +612,52 @@ def links(tree: RepoTree) -> list[Launcher]:
     return records
 
 
+# Packages whose build patch replaces the function an emulator resolves a
+# directory with by a fixed path: ROCKNIX's Flycast returns
+# /storage/roms/dreamcast/data as its data directory, which start_flycast.sh
+# then links to the BIOS tree.
+DIRECTORY_PATCHES = (
+    ("flycast", f"{STANDALONE}/flycast-sa/patches/000-conf-dir.patch", "find_user_data_dir"),
+)
+
+
+def patched_directories(tree: RepoTree) -> list[Launcher]:
+    records = []
+    for emulator, path, function in DIRECTORY_PATCHES:
+        lines = tree.read(path).splitlines()
+        target = next(
+            (line[len("+++ b/"):] for line in lines if line.startswith("+++ b/")), None
+        )
+        start = next(
+            (n for n, line in enumerate(lines, 1) if re.search(rf"\b{function}\(\)", line)),
+            None,
+        )
+        returned = None
+        if target is not None and start is not None:
+            returned = next(
+                (
+                    (n, match.group(1))
+                    for n, line in enumerate(lines[start:], start + 1)
+                    if (match := re.match(r'^\+\s*return "(/[^"]+)";', line))
+                ),
+                None,
+            )
+        if returned is None:
+            raise LauncherPatternMissing(path, f"{function}() patched to return a fixed path")
+        number, directory = returned
+        records.append(Launcher(
+            emulator=emulator,
+            build="standalone",
+            kind="passes_path",
+            names=[],
+            source_ref=source_ref([(path, {start, number})]),
+            search_dir=directory.rstrip("/"),
+            passes_to=f"{function}() in {target} returns it",
+            fails_when_missing=False,
+        ))
+    return records
+
+
 def _existence_guard(script: Script, link: Link) -> int | None:
     """The line of a -e test of the BIOS-side path the link waits for, if any."""
     last = max(link.lines)
@@ -639,6 +685,7 @@ EXTRACTORS: tuple[Callable[[RepoTree], list[Launcher]], ...] = (
     duckstation,
     aethersx2,
     armsx2,
+    patched_directories,
     links,
 )