Fix Results tab Metric display names containing replacement syntax

apps/control-panel/src/lib/experiments/metric-names.test.ts

@@ -0,0 +1,42 @@
+import { describe, expect, it } from "vitest";
+import { metricDisplayName, withMetricNames } from "./metric-names";
+
+describe("withMetricNames", () => {
+  it("substitutes an ordinary Metric display name", () => {
+    expect(withMetricNames("metric_x failed", new Map([["metric_x", "Checkout conversion"]]))).toBe(
+      "Checkout conversion failed",
+    );
+  });
+
+  it("treats $& as literal authored text, not the matched Metric id", () => {
+    expect(withMetricNames("metric_x failed", new Map([["metric_x", "Revenue $&"]]))).toBe(
+      "Revenue $& failed",
+    );
+  });
+
+  it("treats $' as literal authored text, not the unmatched suffix", () => {
+    expect(withMetricNames("metric_x failed", new Map([["metric_x", "Revenue $'"]]))).toBe(
+      "Revenue $' failed",
+    );
+  });
+
+  it("treats $ as literal authored text", () => {
+    expect(withMetricNames("metric_x failed", new Map([["metric_x", "Revenue $"]]))).toBe(
+      "Revenue $ failed",
+    );
+  });
+
+  it("leaves a deleted Metric id in place when no display name remains", () => {
+    expect(withMetricNames("metric_x failed", new Map())).toBe("metric_x failed");
+  });
+});
+
+describe("metricDisplayName", () => {
+  it("falls back to the raw Metric id after the catalog entry is gone", () => {
+    expect(metricDisplayName("metric_x", new Map())).toBe("metric_x");
+  });
+
+  it("returns the authored display name when the catalog still has it", () => {
+    expect(metricDisplayName("metric_x", new Map([["metric_x", "Revenue $&"]]))).toBe("Revenue $&");
+  });
+});

apps/control-panel/src/lib/experiments/metric-names.ts

@@ -24,6 +24,6 @@ export function metricDisplayName(metricId: string, names: MetricNames): string
 /** Gate check details arrive as prose with raw Metric ids embedded; rewrite them. */
 export function withMetricNames(text: string, names: MetricNames): string {
   let renamed = text;
-  for (const [id, name] of names) renamed = renamed.replaceAll(id, name);
+  for (const [id, name] of names) renamed = renamed.replaceAll(id, () => name);
   return renamed;
 }