Studio: studio now supports loading self-made layers in themes

src/Models/ThemeConfig/Conversion/Conversion.ts

@@ -39,7 +39,7 @@ export abstract class Conversion<TIn, TOut> {
             ConversionContext.print(msg)
         }
         if (context.hasErrors()) {
-            throw "Detected one or more errors, stopping now"
+            throw new Error(["Detected one or more errors, stopping now:", context.getAll("error").map(e => e.context.path.join(".")+": "+e.message)].join("\n\t"))
         }
         return fixed
     }

src/Models/ThemeConfig/Conversion/PrepareTheme.ts

@@ -186,7 +186,7 @@ class AddDefaultLayers extends DesugaringStep<LayoutConfigJson> {
 
     convert(json: LayoutConfigJson, context: ConversionContext): LayoutConfigJson {
         const state = this._state
-        json.layers = [...(json.layers ?? [])]
+        json.layers = Utils.NoNull([...(json.layers ?? [])])
         const alreadyLoaded = new Set(json.layers.map((l) => l["id"]))
 
         for (const layerName of Constants.added_by_default) {

src/Models/ThemeConfig/Json/LayoutConfigJson.ts

@@ -156,7 +156,7 @@ export interface LayoutConfigJson {
      * type: layer[]
      * types: hidden | layer | hidden
      * group: layers
-     * suggestions: return Array.from(layers.keys()).map(key => ({if: "value="+key, then: key+" - "+layers.get(key).description}))
+     * suggestions: return Array.from(layers.keys()).map(key => ({if: "value="+key, then: "<b>"+key+"</b> (builtin) - "+layers.get(key).description}))
      * Every layer contains a description of which feature to display - the overpassTags which are queried.
      * Instead of running one query for every layer, the query is fused.
      *

src/Models/ThemeConfig/TagRenderingConfig.ts

@@ -233,7 +233,7 @@ export default class TagRenderingConfig {
             }
 
             const firstMappingSize: string = json.mappings
-                .map((m) => m.icon?.["class"])
+                .map((m) => m?.icon?.["class"])
                 .find((c) => !!c)
             const commonIconSize = firstMappingSize ?? json["#iconsize"] ?? "small"
             this.mappings = json.mappings.map((m, i) =>