Garbage collect properties when change type #42

src/libs/layer.js

@@ -0,0 +1,24 @@
+import GlSpec from 'mapbox-gl-style-spec/reference/latest.js'
+
+export function changeType(layer, newType) {
+  const changedPaintProps = { ...layer.paint }
+  Object.keys(changedPaintProps).forEach(propertyName => {
+    if(!(propertyName in GlSpec['paint_' + newType])) {
+      delete changedPaintProps[propertyName]
+    }
+  })
+
+  const changedLayoutProps = { ...layer.layout }
+  Object.keys(changedLayoutProps).forEach(propertyName => {
+    if(!(propertyName in GlSpec['layout_' + newType])) {
+      delete changedLayoutProps[propertyName]
+    }
+  })
+
+  return {
+    ...layer,
+    paint: changedPaintProps,
+    layout: changedLayoutProps,
+    type: newType,
+  }
+}