feat(scenarios): add meter-value-negative to the corpus

.changeset/add-meter-value-negative.md

@@ -0,0 +1,5 @@
+---
+'@ocpp-debugkit/toolkit': patch
+---
+
+meter-value-negative: add a scenario that drives the negative branch of METER_VALUE_ANOMALY. The register reads -50 Wh, which is physically impossible, so the rule fires. meter-anomaly only covers the decreasing branch, so this is the missing half.

README.md

@@ -22,7 +22,7 @@ validate behavior against known scenarios.
   firmware update failures, suspicious session duration, slow CSMS responses,
   heartbeat interval violations, meter value anomalies, unresponsive CSMS, and
   repeated boot notifications.
-- **Scenario Evaluator** — 23 predefined scenarios with expected failure
+- **Scenario Evaluator** — 24 predefined scenarios with expected failure
   outcomes for testing the analysis engine. Supports external scenario files.
 - **Replay Engine** — Deterministic, pure replay engine with step forward/back,
   jump-to-event, and configurable playback speed.

packages/toolkit/README.md

@@ -20,7 +20,7 @@ report generation, React components, and CLI.
   firmware update failures, suspicious session duration, slow CSMS responses,
   heartbeat interval violations, meter value anomalies, unresponsive CSMS, and
   repeated boot notifications.
-- **Scenario Evaluator** — 23 predefined scenarios with expected failure
+- **Scenario Evaluator** — 24 predefined scenarios with expected failure
   outcomes for testing the analysis engine. Supports external scenario files.
 - **Replay Engine** — Deterministic, pure replay engine with step forward/back,
   jump-to-event, and configurable playback speed. No timers or I/O.

packages/toolkit/src/scenarios/__scenarios__/meter-value-negative.ts

@@ -0,0 +1,114 @@
+export default {
+  name: 'meter-value-negative',
+  description:
+    'Cumulative energy register goes negative during a transaction. A negative reading is physically impossible and triggers METER_VALUE_ANOMALY.',
+  trace: {
+    traceId: 'scenario-meter-value-negative',
+    metadata: {
+      stationId: 'CS-SYNTHETIC-025',
+      ocppVersion: '1.6',
+      source: 'synthetic-scenario',
+      description:
+        'Station reports a negative cumulative register (-50 Wh) — the register can never go below zero.',
+    },
+    events: [
+      {
+        timestamp: '2026-03-01T09:00:00.000Z',
+        direction: 'CS_TO_CSMS',
+        message: [
+          2,
+          'msg-001',
+          'BootNotification',
+          {
+            chargePointVendor: 'SyntheticVendor',
+            chargePointModel: 'SM-100',
+            chargePointSerialNumber: 'CS-SYNTHETIC-025',
+            firmwareVersion: '1.0.0',
+          },
+        ],
+      },
+      {
+        timestamp: '2026-03-01T09:00:00.500Z',
+        direction: 'CSMS_TO_CS',
+        message: [3, 'msg-001', { currentTime: '2026-03-01T09:00:00.500Z', interval: 300, status: 'Accepted' }],
+      },
+      {
+        timestamp: '2026-03-01T09:00:30.000Z',
+        direction: 'CS_TO_CSMS',
+        message: [2, 'msg-002', 'Authorize', { idTag: 'SYNTHETIC-TAG-025' }],
+      },
+      {
+        timestamp: '2026-03-01T09:00:30.500Z',
+        direction: 'CSMS_TO_CS',
+        message: [3, 'msg-002', { idTagInfo: { status: 'Accepted' } }],
+      },
+      {
+        timestamp: '2026-03-01T09:01:00.000Z',
+        direction: 'CS_TO_CSMS',
+        message: [
+          2,
+          'msg-003',
+          'StartTransaction',
+          { connectorId: 1, idTag: 'SYNTHETIC-TAG-025', meterStart: 0 },
+        ],
+      },
+      {
+        timestamp: '2026-03-01T09:01:00.500Z',
+        direction: 'CSMS_TO_CS',
+        message: [3, 'msg-003', { idTagInfo: { status: 'Accepted' }, transactionId: 100025 }],
+      },
+      {
+        timestamp: '2026-03-01T09:02:00.000Z',
+        direction: 'CS_TO_CSMS',
+        message: [
+          2,
+          'msg-004',
+          'MeterValues',
+          {
+            connectorId: 1,
+            transactionId: 100025,
+            meterValue: [
+              {
+                sampledValue: [
+                  { value: '-50', measurand: 'Energy.Active.Import.Register', unit: 'Wh' },
+                ],
+              },
+            ],
+          },
+        ],
+      },
+      {
+        timestamp: '2026-03-01T09:02:00.500Z',
+        direction: 'CSMS_TO_CS',
+        message: [3, 'msg-004', {}],
+      },
+      {
+        timestamp: '2026-03-01T09:05:00.000Z',
+        direction: 'CS_TO_CSMS',
+        message: [
+          2,
+          'msg-005',
+          'StopTransaction',
+          {
+            transactionId: 100025,
+            idTag: 'SYNTHETIC-TAG-025',
+            meterStop: 0,
+            reason: 'Local',
+          },
+        ],
+      },
+      {
+        timestamp: '2026-03-01T09:05:00.500Z',
+        direction: 'CSMS_TO_CS',
+        message: [3, 'msg-005', { idTagInfo: { status: 'Accepted' } }],
+      },
+    ],
+  },
+  expectedFailures: ['METER_VALUE_ANOMALY'],
+  assertions: [
+    {
+      type: 'failure_count',
+      params: { code: 'METER_VALUE_ANOMALY', min: 1 },
+    },
+  ],
+};

packages/toolkit/src/scenarios/index.test.ts

@@ -26,6 +26,7 @@ import {
   meterValueZeroScenario,
   statusTransitionsLegalScenario,
   bootOutsideRepeatWindowScenario,
+  meterValueNegativeScenario,
 } from './index.js';
 import { parseTrace, buildSessionTimeline, detectFailures } from '../core/index.js';
 
@@ -34,8 +35,8 @@ import { parseTrace, buildSessionTimeline, detectFailures } from '../core/index.
 // ---------------------------------------------------------------------------
 
 describe('scenario registry', () => {
-  it('exports exactly 23 scenarios', () => {
-    expect(scenarios).toHaveLength(23);
+  it('exports exactly 24 scenarios', () => {
+    expect(scenarios).toHaveLength(24);
   });
 
   it('exports scenario names in order', () => {
@@ -63,6 +64,7 @@ describe('scenario registry', () => {
       'meter-value-zero',
       'status-transitions-legal',
       'boot-outside-repeat-window',
+      'meter-value-negative',
     ]);
   });
 
@@ -99,6 +101,7 @@ describe('scenario registry', () => {
     expect(getScenario('meter-value-zero')).toBe(meterValueZeroScenario);
     expect(getScenario('status-transitions-legal')).toBe(statusTransitionsLegalScenario);
     expect(getScenario('boot-outside-repeat-window')).toBe(bootOutsideRepeatWindowScenario);
+    expect(getScenario('meter-value-negative')).toBe(meterValueNegativeScenario);
   });
 
   it('getScenario returns undefined for unknown name', () => {
@@ -278,6 +281,14 @@ describe('scenario engine integration', () => {
     const failures = detectFailures(result.events, sessions);
     expect(failures).toHaveLength(0);
   });
+
+  it('meter-value-negative: detects METER_VALUE_ANOMALY', () => {
+    const trace = JSON.stringify(meterValueNegativeScenario.trace);
+    const result = parseTrace(trace);
+    const sessions = buildSessionTimeline(result.events);
+    const failures = detectFailures(result.events, sessions);
+    expect(failures.some((f) => f.code === 'METER_VALUE_ANOMALY')).toBe(true);
+  });
 });
 
 // ---------------------------------------------------------------------------

packages/toolkit/src/scenarios/index.ts

@@ -28,6 +28,7 @@ import repeatedBootNotification from './__scenarios__/repeated-boot-notification
 import meterValueZero from './__scenarios__/meter-value-zero.js';
 import statusTransitionsLegal from './__scenarios__/status-transitions-legal.js';
 import bootOutsideRepeatWindow from './__scenarios__/boot-outside-repeat-window.js';
+import meterValueNegative from './__scenarios__/meter-value-negative.js';
 
 // ---------------------------------------------------------------------------
 // Scenarios derived from core fixtures
@@ -82,6 +83,7 @@ const repeatedBootNotificationScenario: Scenario = repeatedBootNotification as u
 const meterValueZeroScenario: Scenario = meterValueZero as unknown as Scenario;
 const statusTransitionsLegalScenario: Scenario = statusTransitionsLegal as unknown as Scenario;
 const bootOutsideRepeatWindowScenario: Scenario = bootOutsideRepeatWindow as unknown as Scenario;
+const meterValueNegativeScenario: Scenario = meterValueNegative as unknown as Scenario;
 
 // ---------------------------------------------------------------------------
 // Registry
@@ -111,6 +113,7 @@ export const scenarios = [
   meterValueZeroScenario,
   statusTransitionsLegalScenario,
   bootOutsideRepeatWindowScenario,
+  meterValueNegativeScenario,
 ] as const;
 
 export const scenarioNames = [
@@ -137,6 +140,7 @@ export const scenarioNames = [
   'meter-value-zero',
   'status-transitions-legal',
   'boot-outside-repeat-window',
+  'meter-value-negative',
 ] as const;
 
 export {
@@ -163,6 +167,7 @@ export {
   meterValueZeroScenario,
   statusTransitionsLegalScenario,
   bootOutsideRepeatWindowScenario,
+  meterValueNegativeScenario,
 };
 
 export { compareScenarioReports } from './compare.js';

tests/external-fixture/test.mjs

@@ -158,8 +158,8 @@ const scenarios = await import('@ocpp-debugkit/toolkit/scenarios');
 
 assert(Array.isArray(scenarios.scenarios), 'scenarios is an array');
 assert(
-  scenarios.scenarios.length === 23,
-  `23 scenarios exported (got ${scenarios.scenarios.length})`,
+  scenarios.scenarios.length === 24,
+  `24 scenarios exported (got ${scenarios.scenarios.length})`,
 );
 assert(typeof scenarios.getScenario === 'function', 'getScenario is a function');
 assert(scenarios.getScenario('normal-session') !== undefined, 'normal-session scenario exists');