[1844] Error in `determine_sbb_president!`

[Mage837]

1844 Game won't allow BLS to purchase train

Game ID 216922

https://18xx.games/game/216922

When trying purchase a 5H or any train for the BLS an error message appears that reads "Undefined method 'share' for Engine::G1844::Game -1844"

How to Reproduce the Bug?

BLS withheld Revenue during operating round 7.2 (of 2) when trying to purchase a train the previous error message appears.

Please include screenshots (you can drag and drop or upload them into this issue)

I am playing this on my mobile phone.

[ollybh]

The error isn't anything to do with the train purchasing, it also occurs if BLS passes. BLS is the last company to operate in the operating round, and the game is attempting to move on to the next stock round. The error is occurring in the code for determining SBB’s president:

Caught exception #<NoMethodError: undefined method `share' for Engine::Game::G1844::Game - 1844 PurpleFrogPlays,Corian09,Mage837,Joshua6,ARandomPun>, backtrace: [
assets/deps.js:1563:35:in `klass.method_missing_stub'
assets/g_1844.js:609:104:in `klass.$Game_determine_sbb_president$excl$49'
/assets/g_1844.js:482:53:in `klass.$Game_form_sbb$excl$39'
/assets/g_1844.js:1557:45:in `klass.$$setup'
/assets/main.js:8053:22:in `klass.$$finalize_round_setup'
/assets/main.js:8045:23:in `klass.$Base_transition_to_next_round$excl$23'
/assets/main.js:8014:51:in `klass.$$process_single_action'
/assets/main.js:7944:18:in `klass.$$process_action'
/assets/main.js:41793:30:in `klass.$$process_action'
/assets/main.js:55533:25:in `Object.$$1'
/assets/deps.js:27419:13:in `invokeHandler'
/assets/deps.js:27433:5:in `handleEvent'
/assets/deps.js:27439:5:in `HTMLButtonElement.handler']

[ollybh]

This error is coming at line 532 of determine_sbb_president!. A share variable isn't set anywhere in this method, so we're getting the missing method error.

18xx/lib/engine/game/g_1844/game.rb

Lines 515 to 542 in 200da5e

	def determine_sbb_president!(president_priority_order)
	player_share_percent = sbb.player_share_holders
	max_percent = player_share_percent.values.max || 0
	return if max_percent < 10
	# Determine president
	candidates = player_share_percent.select { |_, percent| percent == max_percent }.keys
	if candidates.size > 1
	candidates.sort_by! { |player| president_priority_order.index(player) || president_priority_order.size }
	end
	president = candidates.first
	# Make sure president has a 10% cert
	if (president_shares = president.shares_of(sbb)).none? { |share| share.percent == 10 }
	ten_percent_share = @share_pool.shares_of(sbb).find { |share| share.percent == 10 } ||
	president_priority_order[-1].shares_of(sbb).find { |share| share.percent == 10 }
	@share_pool.transfer_shares(ShareBundle.new([ten_percent_share]), president, allow_president_change: false)
	@share_pool.transfer_shares(ShareBundle.new(president_shares.take(2)), share.owner, allow_president_change: false)
	end
	# Make sure president has the presidents cert
	if (presidents_share_owner = sbb.presidents_share.owner) != president
	@share_pool.transfer_shares(ShareBundle.new([sbb.presidents_share]), president)
	@share_pool.transfer_shares(
	ShareBundle.new([president_shares.find { |share| !share.president && share.percent == 10 }]),
	presidents_share_owner
	)
	end

The SBB is forming and Corian09 is the new president. They weren't the president of any pre-SBB companies so hadn't been allocated any 10% shares. This code is attempting to swap a couple of 5% shares for a 10% share.

There's not been any changes to this method, so this bug must have been present since this code was added. This situation must not happen often.