test(P4.01): strengthen clamp assertions with overflow and precise value checks [codexPreflight]

Author: cesarnml

src/lib/components/BarChart/barChartHelpers.spec.ts

@@ -36,6 +36,62 @@ describe('createActiveHoursData', () => {
 
     const result = createActiveHoursData(durations)
     const values = result.map((item) => item.value)
+    expect(values[10]).toBe(0)
     expect(values.every((v) => v >= 0)).toBe(true)
   })
+
+  it('clamps same-hour accumulation at zero when a reversed segment exceeds prior minutes', () => {
+    const durations: SupabaseDuration = {
+      id: 'test',
+      created_at: '2024-01-01',
+      updated_at: '2024-01-01',
+      date: '2024-01-01',
+      data: [
+        {
+          time: 1704103200, // 2024-01-01 10:00 AM UTC
+          duration: 1200, // +20 minutes
+          color: null,
+          project: 'test',
+          language: 'TypeScript',
+          category: 'coding',
+          entity: 'test.ts',
+          branch: 'main',
+          ai_session: null,
+          ai_additions: 0,
+          ai_deletions: 0,
+          human_additions: 0,
+          human_deletions: 0,
+          ai_input_tokens: 0,
+          ai_output_tokens: 0,
+          ai_prompt_length_sum: 0,
+          ai_prompt_events: 0,
+        },
+        {
+          time: 1704105000, // 2024-01-01 10:30 AM UTC
+          duration: -1800, // -30 minutes, would underflow without clamping acc + delta
+          color: null,
+          project: 'test',
+          language: 'TypeScript',
+          category: 'coding',
+          entity: 'test.ts',
+          branch: 'main',
+          ai_session: null,
+          ai_additions: 0,
+          ai_deletions: 0,
+          human_additions: 0,
+          human_deletions: 0,
+          ai_input_tokens: 0,
+          ai_output_tokens: 0,
+          ai_prompt_length_sum: 0,
+          ai_prompt_events: 0,
+        },
+      ],
+    }
+
+    const result = createActiveHoursData(durations)
+    const values = result.map((item) => item.value)
+
+    expect(values[10]).toBe(0)
+    expect(values.every((value, index) => index === 10 || value === 0)).toBe(true)
+  })
 })