Complete resilient Steam login flow

tests/steam_login_test.gd

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+extends SceneTree
+
+var failures := 0
+var login: Control
+
+
+func _initialize() -> void:
+	call_deferred("_run")
+
+
+func _run() -> void:
+	login = load("res://scripts/ui/login_screen.gd").new()
+	root.add_child(login)
+	await process_frame
+	_test_elapsed_timeout_clears_flow()
+	_test_transient_failure_keeps_transaction()
+	_test_leaving_completion_cancels_flow()
+	login.queue_free()
+	await process_frame
+	quit(1 if failures > 0 else 0)
+
+
+func _test_elapsed_timeout_clears_flow() -> void:
+	login.steam_transaction_id = "expired-transaction"
+	login.steam_poll_deadline_msec = 1
+	login.poll_timer.start()
+	login._poll_steam()
+	_assert(login.steam_transaction_id.is_empty(), "elapsed Steam login deadline should clear the transaction")
+	_assert(login.poll_timer.is_stopped(), "elapsed Steam login deadline should stop polling")
+
+
+func _test_transient_failure_keeps_transaction() -> void:
+	login.steam_transaction_id = "retry-transaction"
+	login.steam_poll_deadline_msec = Time.get_ticks_msec() + 300000
+	login.steam_poll_failures = 2
+	login._on_steam_status(HTTPRequest.RESULT_CANT_CONNECT, 0, PackedStringArray(), PackedByteArray())
+	_assert(login.steam_transaction_id == "retry-transaction", "temporary connection failures should preserve the Steam transaction")
+	_assert(login.steam_poll_failures == 3, "temporary connection failures should be tracked without consuming the deadline")
+
+
+func _test_leaving_completion_cancels_flow() -> void:
+	login.mode = "steam"
+	login.steam_transaction_id = "cancel-transaction"
+	login.poll_timer.start()
+	login._set_mode("login")
+	_assert(login.steam_transaction_id.is_empty(), "leaving Steam account completion should clear its transaction")
+	_assert(login.poll_timer.is_stopped(), "leaving Steam account completion should stop polling")
+
+
+func _assert(condition: bool, message: String) -> void:
+	if condition:
+		return
+	failures += 1
+	push_error(message)

tests/steam_login_test.gd.uid

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+uid://cnqc7wymmiwdd