Fix interleaved text and choices

anselme/state/event_manager.lua

@@ -1,7 +1,7 @@
 local class = require("anselme.lib.class")
 
 local ast = require("anselme.ast")
-local Nil, String, List, Identifier, Boolean = ast.Nil, ast.String, ast.List, ast.Identifier, ast.Boolean
+local Nil, String, List, Identifier = ast.Nil, ast.String, ast.List, ast.Identifier
 
 -- list of event data
 local event_buffer_identifier = Identifier:new("_event_buffer")
@@ -11,9 +11,9 @@ local event_buffer_symbol = event_buffer_identifier:to_symbol{ confined_to_branc
 local last_event_type_identifier = Identifier:new("_last_event_type")
 local last_event_type_symbol = last_event_type_identifier:to_symbol{ confined_to_branch = true }
 
--- indicate if the next flush should be ignored for the current buffered event
-local discard_next_flush_identifier = Identifier:new("_discard_next_flush")
-local discard_next_flush_symbol = discard_next_flush_identifier:to_symbol{ confined_to_branch = true }
+-- (per-scope) indicate if we should discard write to an event type
+local discard_next_events_identifier = Identifier:new("_discard_next_events")
+local discard_next_events_symbol = discard_next_events_identifier:to_symbol{ confined_to_branch = true }
 
 return class {
 	init = false,
@@ -21,38 +21,48 @@ return class {
 	setup = function(self, state)
 		state.scope:define(event_buffer_symbol, List:new(state))
 		state.scope:define(last_event_type_symbol, Nil:new())
-		state.scope:define(discard_next_flush_symbol, Nil:new())
 	end,
 	reset = function(self, state)
 		state.scope:set(event_buffer_identifier, List:new(state))
 		state.scope:set(last_event_type_identifier, Nil:new())
-		state.scope:set(discard_next_flush_identifier, Nil:new())
 	end,
 
 	-- write an event into the event buffer
 	-- will flush if an event of a different type is present in the buffer
 	write = function(self, state, event)
+		-- discard if requested
+		if state.scope:defined_in_current(discard_next_events_symbol) then
+			local discard_type = state.scope:get(discard_next_events_identifier):to_lua()
+			if discard_type == event.type then
+				return
+			elseif discard_type ~= nil then
+				state.scope:set(discard_next_events_identifier, Nil:new()) -- fake flush the discarded events
+			end
+		end
+		-- flush until no event or same type
+		repeat
 			local current_type = state.scope:get(last_event_type_identifier):to_lua(state)
 			if current_type ~= nil and current_type ~= event.type then
 				self:flush(state)
 			end
+		until current_type == nil or current_type == event.type
+		-- write
 		state.scope:set(last_event_type_identifier, String:new(event.type))
 		state.scope:get(event_buffer_identifier):insert(state, event)
 	end,
-	-- same as :write, but the buffer will be discarded instead of yielded on the next flush
-	write_and_discard_on_flush = function(self, state, event)
-		self:write(state, event)
-		state.scope:set(discard_next_flush_identifier, Boolean:new(true))
+	-- same as :write, but will not actually write the event, instead discarding all immediately following event of the same type in the same scope
+	write_and_discard_following = function(self, state, event)
+		if not state.scope:defined_in_current(discard_next_events_symbol) then
+			state.scope:define(discard_next_events_symbol, String:new(event.type))
+		else
+			state.scope:set(discard_next_events_identifier, String:new(event.type))
+		end
 	end,
 
 	-- flush the event buffer: build the event data and yield it
 	flush = function(self, state)
 		local last_type = state.scope:get(last_event_type_identifier):to_lua(state)
 		if last_type then
-			local discard_next_flush = state.scope:get(discard_next_flush_identifier):truthy()
-			if discard_next_flush then
-				self:reset(state)
-			else
 			local last_buffer = state.scope:get(event_buffer_identifier)
 			local event_president = last_buffer:get(state, 1) -- elected representative of all concerned events
 			-- yield event data
@@ -63,7 +73,6 @@ return class {
 			-- post callback
 			if event_president.post_flush_callback then event_president:post_flush_callback(state, last_buffer, data) end
 		end
-		end
 	end,
 	-- keep flushing until nothing is left (a flush may re-fill the buffer during its execution)
 	final_flush = function(self, state)

anselme/stdlib/text.lua

@@ -21,7 +21,7 @@ return {
 		function(state, text, func)
 			if func:contains_current_resume_target(state) then
 				func:call(state, ArgumentTuple:new())
-				event_manager:write_and_discard_on_flush(state, Choice:new(text, func))
+				event_manager:write_and_discard_following(state, Choice:new(text, func))
 			else
 				event_manager:write(state, Choice:new(text, func))
 			end

test/results/choice text interleaved.ans

@@ -0,0 +1,19 @@
+--# run #--
+--- choice ---
+=> | {}"a" |
+--- text ---
+| {}"-> a" |
+--- choice ---
+=> | {}"aa" |
+ > | {}"ab" |
+--- text ---
+| {}"-> aa" |
+| {}"x" |
+--- choice ---
+=> | {}"b" |
+--- text ---
+| {}"-> b" |
+--- return ---
+()
+--# saved #--
+{}

test/tests/choice text interleaved.ans

@@ -0,0 +1,14 @@
+:@choice = 1
+
+:f = $_
+	| a |>
+		|-> a
+		| aa |>
+			|-> aa
+		| ab |>
+			|-> ab
+	| x
+	| b |>
+		|-> b
+
+f!