perf: diagnoistics improvements

electron/diagnostics/high-memory-alert.rules.spec.ts

@@ -0,0 +1,27 @@
+import {
+  describe,
+  expect,
+  it
+} from 'vitest';
+import {
+  exceedsHighMemoryThreshold,
+  formatWorkingSetGb,
+  HIGH_MEMORY_THRESHOLD_KB
+} from './high-memory-alert.rules';
+
+describe('high-memory-alert.rules', () => {
+  it('uses a 2 GiB working-set threshold', () => {
+    expect(HIGH_MEMORY_THRESHOLD_KB).toBe(2 * 1024 * 1024);
+  });
+
+  it('detects totals at or above the threshold', () => {
+    expect(exceedsHighMemoryThreshold(HIGH_MEMORY_THRESHOLD_KB - 1)).toBe(false);
+    expect(exceedsHighMemoryThreshold(HIGH_MEMORY_THRESHOLD_KB)).toBe(true);
+    expect(exceedsHighMemoryThreshold(HIGH_MEMORY_THRESHOLD_KB + 1024)).toBe(true);
+  });
+
+  it('formats working set totals in gigabytes', () => {
+    expect(formatWorkingSetGb(1536 * 1024)).toBe('1.50');
+    expect(formatWorkingSetGb(HIGH_MEMORY_THRESHOLD_KB)).toBe('2.00');
+  });
+});