fix: read EmuELEC's home in launcher paths

EmuELEC links /storage/.local/share/flycast to /storage/roms/bios/dc
(flycast.sh:11-14 at v4.8), and Flycast reads
$HOME/.local/share/flycast. Root's home there is /storage
(packages/sysutils/busybox/package.mk:168, profile.d/98-busybox.conf:4,
sourced by flycast.sh:7), which nothing recorded, so the link bound
nothing and flycastsa's files went to the BIOS root.

The registry's home_directory now spells that directory as ~ in the
handles and directories of launcher records. flycastsa's ten files
land in bios/dc, where the libretro build already reads them. The
manifest drops dc_boot.bin and dc_nvmem.bin from the BIOS root, which
no emulator reads there, and six arcade archives at the root go back
to the MAME sets the mame cores claim.

platforms/_registry.yml

@@ -931,6 +931,10 @@ platforms:
     # retroarch/package.mk:115 at v4.8) and setsettings.sh never sets it, so
     # RetroArch saves beside each game: no single place.
     save_directory: null
+    # root's home, which every launcher script gets from /etc/profile
+    # (packages/sysutils/busybox/package.mk:168 and
+    # packages/sysutils/busybox/profile.d/98-busybox.conf:4 at v4.8).
+    home_directory: /storage
     schedule: monthly
     target_scraper: emuelec_targets
     target_source: https://github.com/EmuELEC/EmuELEC/blob/dev/packages/sx05re/emuelec/package.mk

scripts/launchers.py

@@ -347,14 +347,19 @@ _HOME = re.compile(r"^(?:\$\{HOME\}|\$HOME|\$home|~)(?=/|$)")
 _FLATPAK_DATA = re.compile(r"^~/\.var/app/[^/]+/data(?=/|$)")
 
 
-def normalize_handle(token: str) -> str:
+def normalize_handle(token: str, home: str = "") -> str:
     """One spelling for a path, setting or function a launcher record names.
 
     ``$home``, ``$HOME``, ``${HOME}`` and ``~`` are one directory, and a
-    Flatpak's data directory is its ``$XDG_DATA_HOME``.
+    Flatpak's data directory is its ``$XDG_DATA_HOME``. ``home`` is the
+    platform's home directory spelled out (``home_directory``): EmuELEC
+    links /storage/.local/share/flycast, Flycast's ~/.local/share/flycast.
     """
     token = token.strip().strip("\"'").rstrip(",;").rstrip("/")
     token = token.removesuffix("()")
+    home = home.rstrip("/")
+    if home and _below(token, home) is not None:
+        token = "~" + token[len(home):]
     token = _HOME.sub("~", token)
     return _FLATPAK_DATA.sub("$XDG_DATA_HOME", token)
 
@@ -464,6 +469,7 @@ def handed_directories(config: dict) -> list[HandedDirectory]:
     holds <system> gives one directory per system the platform declares.
     """
     base = str(config.get("base_destination") or "bios")
+    home = str(config.get("home_directory") or "")
     natives = native_systems(config)
     declared = {d.lower() for d in declared_destinations(config)}
     found: list[HandedDirectory] = []
@@ -490,7 +496,7 @@ def handed_directories(config: dict) -> list[HandedDirectory]:
             if any(re.search(r"[\s,:;]", part) for part in parts):
                 continue
             for part in parts:
-                directory = normalize_handle(part)
+                directory = normalize_handle(part, home)
                 if passes_to.startswith(WORKING_DIRECTORY_PASSED):
                     # The program runs from the directory: what its code
                     # reads through getcwd(), or relative to it, is below it.
@@ -499,7 +505,7 @@ def handed_directories(config: dict) -> list[HandedDirectory]:
                     handles = frozenset(
                         handle
                         for token in passes_to.split()
-                        if (handle := normalize_handle(token)) and handle != directory
+                        if (handle := normalize_handle(token, home)) and handle != directory
                     ) | ini_keys(passes_to)
                 folder = _folder_in_bios(part, base)
                 for emulator in (e.strip() for e in str(record.get("emulator", "")).split(",")):

tests/test_launcher_placement.py

@@ -721,5 +721,31 @@ class Quasi88OnRetroPie(unittest.TestCase):
         )
 
 
+class FlycastOnEmuELEC(unittest.TestCase):
+    """EmuELEC links /storage/.local/share/flycast to bios/dc (flycast.sh:11-14),
+    and root's home is /storage (busybox profile.d/98-busybox.conf:4)."""
+
+    def test_the_home_directory_is_spelled_as_home(self) -> None:
+        from launchers import normalize_handle
+
+        self.assertEqual(
+            normalize_handle("/storage/.local/share/flycast", "/storage"), "~/.local/share/flycast"
+        )
+        self.assertEqual(normalize_handle("/storage", "/storage/"), "~")
+        self.assertEqual(normalize_handle("/storagex/a", "/storage"), "/storagex/a")
+        self.assertEqual(
+            normalize_handle("/storage/.local/share/flycast"), "/storage/.local/share/flycast"
+        )
+
+    def test_the_bios_lands_in_dc(self) -> None:
+        profile = load_emulator_profiles(str(REPO_ROOT / "emulators"))["flycast"]
+        config = load_platform_config("emuelec", str(REPO_ROOT / "platforms"))
+        layouts = platform_layouts("flycast", profile, standalone_set(config))
+        (view,) = [v for v, standalone in layouts if standalone]
+        self.assertTrue(view["files"])
+        for entry in view["files"]:
+            self.assertEqual(entry["standalone_path"], "dc/" + entry["layout_path"])
+
+
 if __name__ == "__main__":
     unittest.main()