test(otel): cover orchestration span timing helpers

Add unit tests for stampOrchestrationStartTime and
resolveOrchestrationSpanBounds used by the backfilled orchestration span
export path in #9794.

Co-authored-by: Cursor <cursoragent@cursor.com>

Author: chemystery09

packages/datadog-instrumentations/test/helpers/otel-orchestration-export.spec.js

@@ -0,0 +1,47 @@
+'use strict'
+
+const assert = require('node:assert/strict')
+
+const { describe, it } = require('mocha')
+
+const {
+  resolveOrchestrationSpanBounds,
+} = require('../../src/helpers/otel-orchestration-export')
+const {
+  stampOrchestrationStartTime,
+} = require('../../src/helpers/otel-orchestration-store')
+
+describe('otel orchestration span timing', () => {
+  describe('stampOrchestrationStartTime', () => {
+    it('stamps the first orchestration turn once', () => {
+      const seeded = {
+        traceId: 'abc',
+        spanId: 'def',
+        pendingStart: true,
+      }
+
+      const first = stampOrchestrationStartTime(seeded, 'PizzaOrderOrchestration')
+      assert.ok(first.startTime)
+      assert.strictEqual(first.pendingStart, undefined)
+
+      const second = stampOrchestrationStartTime(first, 'PizzaOrderOrchestration')
+      assert.strictEqual(second.startTime, first.startTime)
+    })
+  })
+
+  describe('resolveOrchestrationSpanBounds', () => {
+    it('spans the full instance window from first turn through completion', () => {
+      const bounds = resolveOrchestrationSpanBounds({ startTime: 100 }, 350)
+
+      assert.strictEqual(bounds.startTime, 100)
+      assert.strictEqual(bounds.endTime, 350)
+    })
+
+    it('clamps start time when it would exceed the end time', () => {
+      const bounds = resolveOrchestrationSpanBounds({ startTime: 400 }, 350)
+
+      assert.strictEqual(bounds.startTime, 350)
+      assert.strictEqual(bounds.endTime, 350)
+    })
+  })
+})