test(knowledge): cover the capped step budget

Author: waleedlatif1

apps/sim/lib/knowledge/search/budget.test.ts

@@ -44,6 +44,23 @@ describe('search SQL deadline', () => {
     }
   })
 
+  it('caps a step without letting it shorten or outlive the leg it came from', () => {
+    vi.spyOn(performance, 'now').mockReturnValue(0)
+    const controller = new AbortController()
+    const leg = new SearchBudget('vector', 1000, controller.signal)
+    const step = leg.capped(600)
+    expect(step.deadline).toBe(600)
+    expect(step.leg).toBe('vector')
+    expect(step.signal).toBe(controller.signal)
+    /** Spending the step is the step's own business; the leg keeps its deadline and its verdict. */
+    step.isTimeout(new SearchDeadlineError())
+    expect(step.timedOut).toBe(true)
+    expect(leg.timedOut).toBe(false)
+    expect(leg.remaining()).toBe(1000)
+    /** A step longer than what the leg has left cannot extend it. */
+    expect(new SearchBudget('vector', 200).capped(600).deadline).toBe(200)
+  })
+
   it('preserves cancellation and unexpected errors instead of labeling them incomplete evidence', async () => {
     const controller = new AbortController()
     const budget = new SearchBudget('keyword', performance.now() - 1, controller.signal)