avod duplicate columns

src/builder/DataBuilder.ts

@@ -130,7 +130,20 @@ export default class DataBuilder extends LineUpBuilder {
    * @returns {LocalDataProvider}
    */
   buildData() {
-    const columns = this.columns.map((d) => typeof d === 'function' ? d(this.data) : d);
+    // last come survived separted by label to be able to override columns
+    const columns: IColumnDesc[] = [];
+    const contained = new Set<string>();
+    for (const col of this.columns) {
+      const c = typeof col === 'function' ? col(this.data) : col;
+      const key = `${c.type}@${c.label}`;
+      if (!contained.has(key)) {
+        columns.push(c);
+        contained.add(key);
+        continue;
+      }
+      const oldPos = columns.findIndex((d) => key === `${d.type}@${d.label}`);
+      columns.splice(oldPos, 1, c); // replace with new one
+    }
     if (this._deriveColors) {
       deriveColors(columns);
     }

src/builder/adapter/lineup.ts

@@ -126,10 +126,10 @@ export class Adapter {
     this.prevColumns = ctx;
     const columns = ctx.columns.map((d) => Object.assign({}, d)); // work on copy
     if (ctx.deriveColumns) {
-      const labels = new Set(columns.map((d) => d.label));
+      const labels = new Set(columns.map((d) => `${d.type}@${d.label}`));
       const derived = deriveColumnDescriptions(data, {columns: ctx.deriveColumnNames});
       for (const derive of derived) {
-        if (labels.has(derive.label)) { // skip same name
+        if (labels.has(`${derive.type}@${derive.label}`)) { // skip same name
           continue;
         }
         columns.push(derive);