feat: show actual overage percentage in status bar (e.g. 111%)

When overageEnabled is true and overageUsed > 0, compute the display
percentage as 100 + (overageUsed / quota * 100) instead of capping at
the base usedPct. This surfaces overage at a glance without requiring
the user to open the tooltip.

- Extract computeDisplayPct(data) as a named pure function
- Export it for test-only use
- Add 6 unit tests covering normal, edge, and zero-quota cases
- Update README status bar states table (100%+ → 111% example)

Author: euxx

README.md

@@ -27,6 +27,7 @@
 | `25%`          | Normal usage                                       |
 | `75%` (yellow) | Warning threshold reached                          |
 | `90%` (red)    | Critical threshold reached                         |
+| `111%` (red)   | Overage — actual usage exceeds                     |
 | `∞`            | Unlimited plan                                     |
 | `—`            | No premium quota data (plan has no tracked limit)  |
 | `⟳`            | Loading                                            |

src/extension.js

@@ -168,6 +168,19 @@ async function refresh(promptSignIn = false, isManual = false) {
 // Status bar rendering
 // ---------------------------------------------------------------------------
 
+/**
+ * Compute the display percentage for the status bar.
+ * When overage is active, returns the actual total (e.g. 111 when 11% over quota).
+ * @param {import('./api').UsageData} data
+ * @returns {number}
+ */
+function computeDisplayPct(data) {
+  if (data.overageEnabled && data.overageUsed > 0 && data.quota > 0) {
+    return Math.round(100 + (data.overageUsed / data.quota) * 100);
+  }
+  return data.usedPct;
+}
+
 const BILLING_URL = 'https://github.com/settings/billing/premium_requests_usage';
 
 /**
@@ -198,7 +211,7 @@ function updateStatusBar(data, isRateLimited = false) {
     return;
   }
 
-  const pct = data.usedPct;
+  const pct = computeDisplayPct(data);
   let color;
   if (cfg.thresholdEnabled) {
     if (pct >= cfg.thresholdCritical) {
@@ -396,6 +409,7 @@ module.exports = {
   getConfig,
   buildTooltip,
   computeIsStale,
+  computeDisplayPct,
   // Test-only: inspect and mutate module-level state.
   _setState: (s) => {
     if ('isOffline' in s) isOffline = s.isOffline;

tests/extension.test.js

@@ -5,6 +5,7 @@ const {
   getConfig,
   buildTooltip,
   computeIsStale,
+  computeDisplayPct,
   _setState,
   _getState,
   _startRecoveryTimer,
@@ -301,3 +302,36 @@ describe('recovery timer', () => {
     expect(_getState().refreshTimerActive).toBe(true);
   });
 });
+
+// ---------------------------------------------------------------------------
+// computeDisplayPct
+// ---------------------------------------------------------------------------
+
+describe('computeDisplayPct', () => {
+  const base = { usedPct: 70, quota: 100, overageEnabled: false, overageUsed: 0 };
+
+  it('returns usedPct when no overage', () => {
+    expect(computeDisplayPct({ ...base, usedPct: 70 })).toBe(70);
+  });
+
+  it('returns usedPct when overageEnabled but overageUsed is 0', () => {
+    expect(computeDisplayPct({ ...base, overageEnabled: true, overageUsed: 0 })).toBe(70);
+  });
+
+  it('returns usedPct when overageUsed > 0 but overageEnabled is false', () => {
+    expect(computeDisplayPct({ ...base, overageEnabled: false, overageUsed: 10 })).toBe(70);
+  });
+
+  it('returns 110 when 10 of 100 quota used as overage', () => {
+    expect(computeDisplayPct({ ...base, usedPct: 100, overageEnabled: true, overageUsed: 10, quota: 100 })).toBe(110);
+  });
+
+  it('rounds the overage percentage', () => {
+    // 5 overage out of 300 quota = 1.667% overage → rounds to 102
+    expect(computeDisplayPct({ ...base, usedPct: 100, overageEnabled: true, overageUsed: 5, quota: 300 })).toBe(102);
+  });
+
+  it('handles quota of 0 by falling back to usedPct', () => {
+    expect(computeDisplayPct({ ...base, usedPct: 100, overageEnabled: true, overageUsed: 10, quota: 0 })).toBe(100);
+  });
+});