test(trace): add tests for normalizeTraceSpan

Export the function and add unit tests covering event_id→span_id
fallback, existing span_id preservation, and child recursion.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

Author: betegon

src/lib/api-client.ts

@@ -1512,7 +1512,7 @@ export async function getDetailedTrace(
  * ID that `parent_span_id` references on child spans. We copy it to `span_id`
  * so the rest of the codebase can use a single, predictable field name.
  */
-function normalizeTraceSpan(span: TraceSpan): TraceSpan {
+export function normalizeTraceSpan(span: TraceSpan): TraceSpan {
   const normalized = { ...span };
   if (!normalized.span_id && normalized.event_id) {
     normalized.span_id = normalized.event_id;

test/lib/api-client.normalizeTraceSpan.test.ts

@@ -0,0 +1,30 @@
+import { describe, expect, test } from "bun:test";
+import { normalizeTraceSpan } from "../../src/lib/api-client.js";
+
+describe("normalizeTraceSpan", () => {
+  test("copies event_id to span_id when span_id is missing", () => {
+    const span = { event_id: "abc123", start_timestamp: 0 } as Parameters<
+      typeof normalizeTraceSpan
+    >[0];
+    const result = normalizeTraceSpan(span);
+    expect(result.span_id).toBe("abc123");
+  });
+
+  test("preserves existing span_id", () => {
+    const result = normalizeTraceSpan({
+      span_id: "existing",
+      event_id: "other",
+      start_timestamp: 0,
+    });
+    expect(result.span_id).toBe("existing");
+  });
+
+  test("recurses into children", () => {
+    const result = normalizeTraceSpan({
+      span_id: "parent",
+      start_timestamp: 0,
+      children: [{ event_id: "child1", start_timestamp: 1 } as any],
+    });
+    expect(result.children?.[0]?.span_id).toBe("child1");
+  });
+});