Add fix/stuck-merchants

For http://www.bay12games.com/dwarves/mantisbt/view.php?id=9593

Closes DFHack/dfhack#1088

fix/stuck-merchants.lua

@@ -0,0 +1,65 @@
+-- Dismisses stuck merchants that haven't entered the map yet
+
+help = [====[
+
+fix/stuck-merchants
+===================
+
+Dismisses merchants that haven't entered the map yet. This can fix :bug:`9593`.
+This script should probably not be run if any merchants are on the map, so using
+it with `repeat` is not recommended.
+
+Run ``fix/stuck-merchants -n`` or ``fix/stuck-merchants --dry-run`` to list all
+merchants that would be dismissed but make no changes.
+
+]====]
+
+
+function getEntityName(u)
+    local civ = df.historical_entity.find(u.civ_id)
+    if not civ then return 'unknown civ' end
+    return dfhack.TranslateName(civ.name)
+end
+
+function getEntityRace(u)
+    local civ = df.historical_entity.find(u.civ_id)
+    if civ then
+        local craw = df.creature_raw.find(civ.race)
+        if craw then
+            return craw.name[0]
+        end
+    end
+    return 'unknown race'
+end
+
+function dismissMerchants(args)
+    local dry_run = false
+    for _, arg in pairs(args) do
+        if args[1]:match('-h') or args[1]:match('help') then
+            print(help)
+            return
+        elseif args[1]:match('-n') or args[1]:match('dry') then
+            dry_run = true
+        end
+    end
+    for _,u in pairs(df.global.world.units.active) do
+        if u.flags1.merchant and u.flags1.dead then
+            print(('%s unit %d: %s (%s), civ %d (%s, %s)'):format(
+                dry_run and 'Would remove' or 'Removing',
+                u.id,
+                dfhack.df2console(dfhack.TranslateName(dfhack.units.getVisibleName(u))),
+                df.creature_raw.find(u.race).name[0],
+                u.civ_id,
+                dfhack.df2console(getEntityName(u)),
+                getEntityRace(u)
+            ))
+            if not dry_run then
+                u.flags1.left = true
+            end
+        end
+    end
+end
+
+if not dfhack_flags.module then
+    dismissMerchants{...}
+end