Merge pull request #781 from plague006/fix/ent_and_terrain_modules

Switch to functions in table, adjust map_loader accordingly

config.lua

@@ -24,11 +24,11 @@ global.config = {
         ['tiles_per_tick'] = 32,
         -- the entity modules to load (takes a list of requires), example included
         ['entity_modules'] = {
-            -- require('map_gen.entities.fluffy_rainbows')
+            --function() return require('map_gen.entities.fluffy_rainbows') end
         },
         -- the terrain modules to load (takes a list of requires), example included
         ['terrain_modules'] = {
-            --require('map_gen.terrain.tris_chunk_grid')
+            --function() return require('map_gen.terrain.tris_chunk_grid') end
         },
     },
     -- redmew_surface allows a map preset to control world generation as well as map and difficulty settings

map_gen/shared/map_loader.lua

@@ -3,20 +3,45 @@ local b = require 'map_gen.shared.builders'
 local RS = require 'map_gen.shared.redmew_surface'
 local config = global.config.map_generation
 
+local line = '-----------------------------\n'
+local shape_type = type(shape)
+
+--- Check if shape is a function, if it isn't throw an error.
+local function shape_check()
+    if shape_type ~= 'function' then
+        error(line .. 'You cannot use entity or terrain modules together with this map as it does not return a function.')
+    end
+end
+
+--- Run each function once to trigger the require
+local function initialize(array)
+    for i = 1, #array do
+        array[i] = array[i]()
+    end
+end
+
+--- Initializes and applies entity modules after checking for errors.
 if #config.entity_modules > 0 then
+    shape_check()
+    initialize(config.entity_modules)
     shape = shape or b.full_shape
     shape = b.apply_entities(shape, config.entity_modules)
 end
 
+--- Initializes and applies terrain modules after checking for errors.
 if #config.terrain_modules > 0 then
+    shape_check()
+    initialize(config.terrain_modules)
     shape = shape or b.full_shape
 
     for _, m in ipairs(config.terrain_modules) do
         shape = b.overlay_tile_land(shape, m)
     end
 end
-
-if type(shape) == 'function' then
+Debug.print(shape)
+Debug.print(shape_type)
+--- If shape is a function, initialize the generator
+if shape_type == 'function' then
     local surfaces = {
         [RS.get_surface_name()] = shape
     }
@@ -24,6 +49,6 @@ if type(shape) == 'function' then
     local gen = require('map_gen.shared.generate')
     gen.init({surfaces = surfaces, regen_decoratives = config.regen_decoratives, tiles_per_tick = config.tiles_per_tick})
     gen.register()
-elseif shape ~= true then
-    error('You forgot to require a map')
+elseif shape ~= true then -- If a map is returning neither true nor a function, they did not include a map, or the map is returning an unexpected type.
+    error(line .. 'The map selected in map_selection.lua is either missing or is returning a non-true non-function data type.')
 end