don't call value formatter on categories

Author: pan-kot

src/core/__tests__/chart-core-axes.test.tsx

@@ -250,20 +250,17 @@ describe("CoreChart: axes", () => {
     });
   });
 
-  test("uses custom category axes formatters", () => {
-    const valueFormatter = (value: null | number) => ["a", "b"][value!].toUpperCase();
+  test("does not call custom formatter on categorical values", () => {
+    const valueFormatter = vi.fn();
     renderChart({
       highcharts,
       options: {
         series,
-        xAxis: { type: "category", title: { text: "X" } },
-        yAxis: { type: "category", title: { text: "Y" } },
+        xAxis: { type: "category", categories: ["A", "B", "C"], title: { text: "X" }, valueFormatter },
+        yAxis: { type: "category", categories: ["A", "B", "C"], title: { text: "Y" }, valueFormatter },
       },
     });
-    getAxisOptionsFormatters().forEach((formatter) => {
-      expect(formatter.call(mockAxisContext({ type: "category", valueFormatter, value: 0 }))).toBe("A");
-      expect(formatter.call(mockAxisContext({ type: "category", valueFormatter, value: 1 }))).toBe("B");
-    });
+    expect(valueFormatter).not.toHaveBeenCalled();
   });
 
   test("uses custom datetime axes formatters", () => {

src/core/formatters.tsx

@@ -18,13 +18,13 @@ export function getFormatter(axis?: Highcharts.Axis) {
     if (!axis) {
       return `${value}`;
     }
+    if (axis.options.type === "category") {
+      return axis.categories?.[value] ?? value.toString();
+    }
     const axisOptions = axis.userOptions as InternalXAxisOptions | InternalYAxisOptions;
     if (axisOptions.valueFormatter) {
       return axisOptions.valueFormatter(value);
     }
-    if (axis.options.type === "category") {
-      return axis.categories?.[value] ?? value.toString();
-    }
     if (axis.options.type === "datetime") {
       const extremes = axis.getExtremes();
       const formatter = getDefaultDatetimeFormatter([extremes.dataMin, extremes.dataMax]);