fix: a ROCKNIX runner follows its build

ROCKNIX registers DuckStation twice, as the libretro core under retroarch and as duckstation-sa under its own emulator. The exporter looked a standalone runner up as a core name, so standalone DuckStation's 98 additions were written for users of the libretro core, PS2 images included, and standalone ARMSX2 was refused. A libretro runner now answers with the retroarch pair, a standalone with its emulator's own.

scripts/exporter/rocknix_exporter.py

@@ -32,16 +32,27 @@ class Exporter(BatoceraExporter):
 
     def __init__(self) -> None:
         super().__init__()
-        self._emulator_of: dict[str, str] = {}
+        self._pairs: set[tuple[str, str]] = set()
 
     def _runner_pair(self, runner: tuple[bool, str]) -> tuple[str, str | None] | None:
         """ROCKNIX registers libretro cores under `retroarch` and each
         standalone under its own emulator (`azahar azahar-sa`), in the
         emulators package. The `libretro` Batocera writes names nothing
-        there."""
-        _standalone, name = runner
-        emulator = self._emulator_of.get(name)
-        return (emulator, name) if emulator else None
+        there.
+
+        The build decides which registration answers. A libretro core is the
+        `retroarch` pair of that core. A standalone is its own emulator's
+        pair: DuckStation is registered both ways, and looking the standalone
+        up as a core name sent its 98 files to the libretro core's users.
+        """
+        standalone, name = runner
+        if not standalone:
+            return ("retroarch", name) if ("retroarch", name) in self._pairs else None
+        own = sorted(
+            pair for pair in self._pairs
+            if pair[0] == name or (pair[1] == name and pair[0] != "retroarch")
+        )
+        return own[0] if own else None
 
     def render(
         self,
@@ -50,8 +61,8 @@ class Exporter(BatoceraExporter):
         originals: dict[str, str],
         scraped: dict | None = None,
     ) -> dict[str, str]:
-        self._emulator_of = {
-            core: emulator
+        self._pairs = {
+            (emulator, core)
             for _system, emulator, core in _ADD_EMU_CORE.findall(
                 originals.get(EMULATORS_MK, "")
             )

tests/test_exporters.py

@@ -1695,5 +1695,34 @@ class RocknixNamesRunnersItsOwnWay(unittest.TestCase):
         self.assertNotIn("c.bin", text)
 
 
+class RocknixRunnersFollowTheBuild(unittest.TestCase):
+    """ROCKNIX registers DuckStation twice: as the libretro core under
+    retroarch, and as duckstation-sa under its own emulator. The exporter
+    looked a standalone runner up as a core name, gating standalone
+    DuckStation's 98 files on the libretro core, and refused ARMSX2."""
+
+    MK = (
+        "add_emu_core psx retroarch duckstation false\n"
+        "add_emu_core psx duckstation duckstation-sa false\n"
+        "add_emu_core ps2 armsx2 armsx2-sa true\n"
+    )
+
+    def test_each_build_answers_with_its_own_pair(self):
+        from exporter.rocknix_exporter import EMULATORS_MK, Exporter
+
+        exporter = Exporter()
+        exporter._pairs = {
+            (emulator, core)
+            for _s, emulator, core in __import__("re").findall(
+                r"add_emu_core\s+(\S+)\s+(\S+)\s+(\S+)", self.MK
+            )
+        }
+        self.assertEqual(exporter._runner_pair((False, "duckstation")), ("retroarch", "duckstation"))
+        self.assertEqual(exporter._runner_pair((True, "duckstation")), ("duckstation", "duckstation-sa"))
+        self.assertEqual(exporter._runner_pair((True, "armsx2")), ("armsx2", "armsx2-sa"))
+        self.assertIsNone(exporter._runner_pair((False, "armsx2")))
+        self.assertTrue(EMULATORS_MK)
+
+
 if __name__ == "__main__":
     unittest.main()