fix(mobile): in-process launcher return for Android and iOS

Stop joining ChipAudio on every EXIT GAME, always rebuild the Gen1 Game
module on Play-again, and treat iOS like Android for return-to-launcher so
release/mobile LOVE restarts no longer wipe Game.load or crash on quit.

main.lua

@@ -384,12 +384,14 @@ function bootGame(version, cartId)
     Game = require("src.core.Game2").new()
     Game:load()
   else
-    -- Gen1 Game is a module singleton.  In-process EXIT GAME resets it in
-    -- place; if a prior teardown left load missing, rebuild from source.
-    local gameMod = require("src.core.Game")
-    if type(gameMod.load) ~= "function" then
+    -- Gen1 Game is a module singleton.  Always re-require after in-process
+    -- EXIT GAME so a prior session cannot leave a table whose rawget(load)
+    -- is nil (release Android: bootGame then dies with load-a-nil-value).
+    -- rawget: type(mod.load) can lie via __index and skip a rebuild.
     package.loaded["src.core.Game"] = nil
-      gameMod = require("src.core.Game")
+    local gameMod = require("src.core.Game")
+    if type(rawget(gameMod, "load")) ~= "function" then
+      error("src.core.Game missing load after reload")
     end
     Game = gameMod
     Game:load()
@@ -1125,15 +1127,23 @@ function love.quit()
   -- docs/modding.md's core.quit_to_launcher entry) may veto returning to
   -- this Lua launcher via that hook. Vanilla behavior (used when no mod
   -- claims the hook) is exactly the condition below.
-  local isAndroid = (love.system and love.system.getOS and love.system.getOS() == "Android")
+  --
+  -- Android and iOS both tear down LOVE in-process rather than
+  -- love.event.quit("restart"): Android's vendored love.cpp PHYSFS-crashes
+  -- on a second init (#575), and iOS's love.cpp forces DONE_RESTART for
+  -- every quit while warning that leftover threads make that unreliable.
+  -- SessionLifecycle workers (ChipAudio / Fetch / Check) make that warning
+  -- real -- endProcess joins them, then the native restart still blows up.
+  local osName = love.system and love.system.getOS and love.system.getOS()
+  local inProcessReturn = (osName == "Android" or osName == "iOS")
   local wouldReturnToLauncher = PlatformHooks.quitToLauncher(function()
     return Game and not Importer and not quitToLauncher and not scripted
-      and (isAndroid or not launchedIntoGame)
+      and (inProcessReturn or not launchedIntoGame)
   end)
   if wouldReturnToLauncher then
-    if isAndroid then
+    if inProcessReturn then
       returnToLauncher()
-      return true -- abort this quit; the restart lands back in the launcher
+      return true -- abort this quit; stay in the same LOVE run
     end
     quitToLauncher = true
     -- Tell the fresh boot to ignore any boot-straight-into-a-game option this

scripts/build_android.sh

@@ -106,6 +106,13 @@ if [ -n "$TEST_APPLICATION_ID" ]; then
   APPLICATION_ID="$TEST_APPLICATION_ID"
   APP_NAME="$APP_NAME (test)"
 fi
+# Optional overrides for side-by-side test APKs (never used by CI shipping builds).
+if [ -n "${GEN1RECOMP_ANDROID_APPLICATION_ID:-}" ]; then
+  APPLICATION_ID="$GEN1RECOMP_ANDROID_APPLICATION_ID"
+fi
+if [ -n "${GEN1RECOMP_ANDROID_APP_NAME:-}" ]; then
+  APP_NAME="$GEN1RECOMP_ANDROID_APP_NAME"
+fi
 
 # --------------------------------------------------------------- preconditions
 if [ ! -f "$ANDROID_DIR/settings.gradle" ] || [ ! -f "$ANDROID_DIR/gradlew" ]; then

src/core/HostShell.lua

@@ -158,7 +158,15 @@ end
 -- and the app dies. There we relaunch through the GameActivity.restartApp
 -- JNI bridge (love.system.restartApp), which schedules our launch intent
 -- and kills the process so no native state can leak into the fresh run.
--- On every other platform the in-process restart works, so keep it.
+-- iOS is the same class of problem with a sharper edge: love.cpp under
+-- LOVE_IOS forces DONE_RESTART for *every* quit (Apple forbids programmatic
+-- exit) and comments that leftover threads make that restart unreliable --
+-- which our ChipAudio / Fetch / Check workers are.  There is no
+-- restartApp bridge on iOS, so callers that want "back to launcher" must
+-- use main.lua's in-process returnToLauncher (love.quit aborts the quit);
+-- HostShell.restart itself refuses quit("restart") and falls back to a
+-- bare quit() so a mod that still calls restart does not pick the worst
+-- path on purpose.
 function HostShell.restart()
   if not (love and love.event and love.event.quit) then return end
 
@@ -174,6 +182,14 @@ function HostShell.restart()
     love.event.quit()
     return
   end
+  if osName == "iOS" then
+    -- No process-kill bridge.  A bare quit still becomes DONE_RESTART in
+    -- love.cpp, but quit("restart") is the path that also runs our
+    -- endProcess worker joins first and then re-enters runlove -- the
+    -- combination that crashes EXIT GAME.  Prefer the softer quit.
+    love.event.quit()
+    return
+  end
 
   local appimage = os.getenv("APPIMAGE")
   if not appimage then

src/core/SessionLifecycle.lua

@@ -64,11 +64,18 @@ end
 
 -- EXIT GAME / intent_game before dropping Game.  Stops audio and resets the
 -- live game instance so map/GPU holders are gone before endMountedSession.
+--
+-- ChipAudio's worker stays alive across game sessions (see tier comment
+-- above).  shutdown() joins the thread and is process-exit only -- calling
+-- it here on every Android EXIT GAME has been observed to leave the Gen1
+-- Game singleton unbootable (Game.load nil) on the next Play of a version
+-- already opened this process, while a debug APK with a different liblove
+-- did not reproduce.
 function SessionLifecycle.endGameSession(game)
   pcall(function() require("src.core.Music").stop() end)
   pcall(function() require("src.core.Sound").stop() end)
   if package.loaded["src.core.ChipAudio"] then
-    pcall(package.loaded["src.core.ChipAudio"].shutdown)
+    pcall(package.loaded["src.core.ChipAudio"].stopMusic)
   end
   if package.loaded["src.core.DiscordPresence"] then
     pcall(package.loaded["src.core.DiscordPresence"].shutdown)
@@ -87,11 +94,11 @@ function SessionLifecycle.endGameSession(game)
   if game and game.reset then
     pcall(function() game:reset() end)
   end
-  -- Gen1 Game is the module singleton.  If teardown left it without load,
-  -- drop the cached module so the next require rebuilds a clean table
-  -- (bootGame also guards this; doing it here keeps Play-again reliable).
-  if game and type(game.load) ~= "function"
-      and package.loaded["src.core.Game"] == game then
+  -- Gen1 Game is the module singleton.  Always drop the cached module after
+  -- a session that owned it so the next bootGame require rebuilds a clean
+  -- table.  A type(game.load) check is not enough: a wrong table parked in
+  -- package.loaded (e.g. with __index) can still look like it has load.
+  if game and package.loaded["src.core.Game"] == game then
     package.loaded["src.core.Game"] = nil
   end
 

tests/engine/android_exit_to_launcher_test.lua

@@ -109,9 +109,35 @@ do
   -- Mimic a shared net module parked on the singleton (handle-style release).
   Game.net = { release = function(id) end }
   SessionLifecycle.endGameSession(Game)
+  check(package.loaded["src.core.Game"] == nil,
+    "endGameSession drops the Gen1 Game module cache")
   local again = require("src.core.Game")
-  check(type(again.load) == "function",
+  check(type(rawget(again, "load")) == "function",
     "Play-again can call Game:load after endGameSession")
+  check(again ~= Game, "Play-again gets a fresh Gen1 Game module table")
+end
+
+-- 7. endGameSession must not join the ChipAudio worker (process-tier only).
+--    Joining on every EXIT GAME correlates with release-APK Game.load nil
+--    when reopening a version already played this process.
+do
+  local SessionLifecycle = require("src.core.SessionLifecycle")
+  local ChipAudio = require("src.core.ChipAudio")
+  local shutdownCalls, stopCalls = 0, 0
+  local origShutdown, origStop = ChipAudio.shutdown, ChipAudio.stopMusic
+  ChipAudio.shutdown = function(...)
+    shutdownCalls = shutdownCalls + 1
+    return origShutdown(...)
+  end
+  ChipAudio.stopMusic = function(...)
+    stopCalls = stopCalls + 1
+    return origStop(...)
+  end
+  local game = { reset = function() end, load = function() end }
+  SessionLifecycle.endGameSession(game)
+  ChipAudio.shutdown, ChipAudio.stopMusic = origShutdown, origStop
+  eq(shutdownCalls, 0, "endGameSession does not ChipAudio.shutdown")
+  check(stopCalls >= 1, "endGameSession stops chip music (Music.stop and/or stopMusic)")
 end
 
 T.finish("android_exit_to_launcher_test")

tests/engine/host_restart_android_bug575.lua

@@ -4,7 +4,10 @@
 -- The fix prefers the love.system.restartApp JNI bridge (which kills the
 -- process, so a true return is never observed live) and, on an old APK
 -- whose liblove lacks the bridge, falls back to a CLEAN quit with no
--- argument.  Desktop keeps the in-process quit("restart").
+-- argument.  iOS has no restartApp bridge and love.cpp forces DONE_RESTART
+-- for every quit; HostShell.restart must still refuse quit("restart") so a
+-- leftover caller does not pick the worker-join + native-restart path that
+-- crashes EXIT GAME.  Desktop keeps the in-process quit("restart").
 --   luajit tests/engine/host_restart_android_bug575.lua
 
 package.path = "./?.lua;./?/init.lua;" .. package.path
@@ -48,12 +51,18 @@ HostShell.restart()
 eq(#quits, 2, "a bridge-less APK quits cleanly instead of crashing")
 eq(quits[2].n, 0, "again with no restart argument")
 
+-- iOS: no process-kill bridge; never quit("restart")
+osName = "iOS"
+HostShell.restart()
+eq(#quits, 3, "iOS HostShell.restart still quits once")
+eq(quits[3].n, 0, "iOS uses a bare quit(), never quit(\"restart\")")
+
 -- desktop (no AppImage in a test environment) keeps the in-process restart
 if not os.getenv("APPIMAGE") then
   osName = "OS X"
   HostShell.restart()
-  eq(quits[3] and quits[3].arg, "restart",
-     "non-Android still restarts in-process")
+  eq(quits[4] and quits[4].arg, "restart",
+     "non-mobile still restarts in-process")
 end
 
 T.finish("host_restart_android_bug575")

tests/engine/launcher_session_teardown_test.lua

@@ -64,12 +64,17 @@ do
   Game.linkFetch = {
     release = function(id) jobs[id] = nil end,
   }
+  local before = Game
   SessionLifecycle.endGameSession(Game)
-  check(type(Game.load) == "function",
-    "endGameSession leaves Game.load intact for the next bootGame")
-  check(package.loaded["src.core.Game"] == Game
-      or type((package.loaded["src.core.Game"] or {}).load) == "function",
-    "Gen1 Game module remains require-able after endGameSession")
+  check(type(before.load) == "function",
+    "endGameSession reset leaves methods on the old table")
+  check(package.loaded["src.core.Game"] == nil,
+    "endGameSession drops Gen1 Game from package.loaded")
+  local again = require("src.core.Game")
+  check(type(rawget(again, "load")) == "function",
+    "require rebuilds a bootable Gen1 Game after endGameSession")
+  check(again ~= before, "Play-again uses a fresh Gen1 Game module table")
+  Game = again
 end
 
 -- ---- Game2:reset releases world GPU and present canvases ------------------

tests/engine/quit_thread_shutdown.lua

@@ -197,6 +197,16 @@ check(source("src/update/Check.lua"):find("registerProcessShutdown(Check.shutdow
 check(source("src/net/Fetch.lua"):find("registerProcessShutdown(Fetch.shutdown)", 1, true) ~= nil,
       "Fetch registers its shutdown hook at load")
 
+-- iOS EXIT GAME must share Android's in-process returnToLauncher: love.cpp
+-- under LOVE_IOS forces DONE_RESTART for every quit and warns that leftover
+-- threads make that restart unreliable (ChipAudio / Fetch / Check).
+check(quitHook:find('osName == "Android" or osName == "iOS"', 1, true) ~= nil,
+      "love.quit treats Android and iOS as in-process return platforms")
+check(quitHook:find("inProcessReturn", 1, true) ~= nil,
+      "love.quit gates returnToLauncher on inProcessReturn")
+check(quitHook:find('require("src.core.HostShell").restart()', 1, true) ~= nil,
+      "desktop return-to-launcher still reaches HostShell.restart")
+
 -- The Android half: LOVE keeps the JVM process after the native main returns,
 -- so the quit event exits the process outright.  It has to sit after the
 -- love.quit() veto test, or the editor's abort-quit path would die on a quit