Fix clear-smoke memory leaks

changelog.txt

@@ -56,6 +56,7 @@ Template for new versions:
 - `quickfort`: allow farm plots to be built on muddy stone
 - `suspend`: remove broken ``--onlyblocking`` option; restore functionality to ``suspend all``
 - `gui/create-item`: allow creation of adamantine thread, wool, and yarn
+- `clear-smoke`: fix memory leak caused by the smoke flow not being deleted from memory
 
 ## Misc Improvements
 - `gui/launcher`: "space space to toggle pause" behavior is skipped if the game was paused when `gui/launcher` came up to prevent accidental unpausing

clear-smoke.lua

@@ -1,25 +1,28 @@
--- Removes all smoke from the map
-
---[====[
-
-clear-smoke
-===========
-
-Removes all smoke from the map. Note that this can leak memory and should be
-used sparingly.
-
-]====]
+local flows_to_delete = {}
 
 function clearSmoke(flows)
+    local success
     for i = #flows - 1, 0, -1 do
-        if flows[i].type == df.flow_type.Smoke then
+        local flow = flows[i]
+        if flow.type == df.flow_type.Smoke then
             flows:erase(i)
+            flows_to_delete[flow] = true
+            success = true
         end
     end
+    return success
 end
 
 clearSmoke(df.global.flows)
 
-for _, block in pairs(df.global.world.map.map_blocks) do
-    clearSmoke(block.flows)
+for _,block in pairs(df.global.world.map.map_blocks) do
+    if clearSmoke(block.flows) then
+        dfhack.maps.enableBlockUpdates(block, true)
+    end
 end
+
+for flow,_ in pairs(flows_to_delete) do
+    if flow then
+        flow:delete()
+    end
+end

docs/clear-smoke.rst

@@ -5,7 +5,6 @@ clear-smoke
     :summary: Removes all smoke from the map.
     :tags: fort armok fps map
 
-Note that this can leak memory and should be used sparingly.
 
 Usage
 -----