test(ocpp): add OCPPServiceUtils pure function tests

Test getMessageTypeString, ajvErrorsToErrorType,
convertDateToISOString, isConnectorIdValid — 19 tests
covering the shared base layer with zero mocking.

diff --git a/tests/charging-station/ocpp/OCPPServiceUtils-pure.test.ts b/tests/charging-station/ocpp/OCPPServiceUtils-pure.test.ts
new file mode 100644 (file)
index 0000000..6c954c0
--- /dev/null
+++ b/tests/charging-station/ocpp/OCPPServiceUtils-pure.test.ts
@@ -0,0 +1,180 @@
+/**
+ * @file Tests for OCPPServiceUtils pure functions
+ * @description Verifies pure utility functions exported from OCPPServiceUtils
+ *
+ * Covers:
+ * - getMessageTypeString — converts MessageType enum to human-readable string
+ * - ajvErrorsToErrorType — maps AJV validation errors to OCPP ErrorType
+ * - convertDateToISOString — recursively converts Date objects to ISO strings in-place
+ * - OCPPServiceUtils.isConnectorIdValid — validates connector ID ranges
+ */
+
+import type { ErrorObject } from 'ajv'
+
+import { expect } from '@std/expect'
+import { afterEach, describe, it } from 'node:test'
+
+import type { ChargingStation } from '../../../src/charging-station/ChargingStation.js'
+
+import {
+  ajvErrorsToErrorType,
+  convertDateToISOString,
+  getMessageTypeString,
+} from '../../../src/charging-station/ocpp/OCPPServiceUtils.js'
+import { OCPPServiceUtils } from '../../../src/charging-station/ocpp/OCPPServiceUtils.js'
+import {
+  ErrorType,
+  IncomingRequestCommand,
+  type JsonType,
+  MessageType,
+} from '../../../src/types/index.js'
+import { standardCleanup } from '../../helpers/TestLifecycleHelpers.js'
+
+/**
+ *
+ * @param keyword
+ */
+function makeAjvError (keyword: string): ErrorObject {
+  return {
+    instancePath: '',
+    keyword,
+    params: {},
+    schemaPath: `#/${keyword}`,
+  } as ErrorObject
+}
+
+/**
+ *
+ */
+function makeStationStub (): ChargingStation {
+  return { logPrefix: () => '[test-station]' } as unknown as ChargingStation
+}
+
+await describe('OCPPServiceUtils — pure functions', async () => {
+  afterEach(() => {
+    standardCleanup()
+  })
+
+  await describe('getMessageTypeString', async () => {
+    await it('should return "request" for MessageType.CALL_MESSAGE', () => {
+      expect(getMessageTypeString(MessageType.CALL_MESSAGE)).toBe('request')
+    })
+
+    await it('should return "response" for MessageType.CALL_RESULT_MESSAGE', () => {
+      expect(getMessageTypeString(MessageType.CALL_RESULT_MESSAGE)).toBe('response')
+    })
+
+    await it('should return "error" for MessageType.CALL_ERROR_MESSAGE', () => {
+      expect(getMessageTypeString(MessageType.CALL_ERROR_MESSAGE)).toBe('error')
+    })
+
+    await it('should return "unknown" for undefined', () => {
+      expect(getMessageTypeString(undefined)).toBe('unknown')
+    })
+  })
+
+  await describe('ajvErrorsToErrorType', async () => {
+    await it('should return FormatViolation for null errors', () => {
+      expect(ajvErrorsToErrorType(null)).toBe(ErrorType.FORMAT_VIOLATION)
+    })
+
+    await it('should return FormatViolation for undefined errors', () => {
+      expect(ajvErrorsToErrorType(undefined)).toBe(ErrorType.FORMAT_VIOLATION)
+    })
+
+    await it('should return FormatViolation for empty errors array', () => {
+      expect(ajvErrorsToErrorType([])).toBe(ErrorType.FORMAT_VIOLATION)
+    })
+
+    await it('should return TypeConstraintViolation for type keyword', () => {
+      expect(ajvErrorsToErrorType([makeAjvError('type')])).toBe(ErrorType.TYPE_CONSTRAINT_VIOLATION)
+    })
+
+    await it('should return OccurrenceConstraintViolation for required keyword', () => {
+      expect(ajvErrorsToErrorType([makeAjvError('required')])).toBe(
+        ErrorType.OCCURRENCE_CONSTRAINT_VIOLATION
+      )
+    })
+
+    await it('should return OccurrenceConstraintViolation for dependencies keyword', () => {
+      expect(ajvErrorsToErrorType([makeAjvError('dependencies')])).toBe(
+        ErrorType.OCCURRENCE_CONSTRAINT_VIOLATION
+      )
+    })
+
+    await it('should return PropertyConstraintViolation for format keyword', () => {
+      expect(ajvErrorsToErrorType([makeAjvError('format')])).toBe(
+        ErrorType.PROPERTY_CONSTRAINT_VIOLATION
+      )
+    })
+
+    await it('should return PropertyConstraintViolation for pattern keyword', () => {
+      expect(ajvErrorsToErrorType([makeAjvError('pattern')])).toBe(
+        ErrorType.PROPERTY_CONSTRAINT_VIOLATION
+      )
+    })
+  })
+
+  await describe('convertDateToISOString', async () => {
+    await it('should convert a Date property to an ISO string', () => {
+      const date = new Date('2025-01-15T10:30:00.000Z')
+      const obj = { timestamp: date } as unknown as JsonType
+      convertDateToISOString(obj)
+      expect((obj as Record<string, unknown>).timestamp).toBe('2025-01-15T10:30:00.000Z')
+    })
+
+    await it('should convert nested Date properties recursively', () => {
+      const date = new Date('2025-06-01T12:00:00.000Z')
+      const obj = { nested: { deep: { created: date } } } as unknown as JsonType
+      convertDateToISOString(obj)
+      expect(
+        ((obj as Record<string, unknown>).nested as Record<string, unknown>).deep as Record<
+          string,
+          unknown
+        >
+      ).toStrictEqual({ created: '2025-06-01T12:00:00.000Z' })
+    })
+
+    await it('should convert Date values inside arrays', () => {
+      const date = new Date('2025-03-10T08:00:00.000Z')
+      const obj = { items: [date] } as unknown as JsonType
+      convertDateToISOString(obj)
+      expect((obj as Record<string, unknown>).items).toStrictEqual(['2025-03-10T08:00:00.000Z'])
+    })
+
+    await it('should not modify non-Date properties', () => {
+      const obj = { active: true, count: 42, name: 'test' } as unknown as JsonType
+      convertDateToISOString(obj)
+      expect(obj).toStrictEqual({ active: true, count: 42, name: 'test' })
+    })
+  })
+
+  await describe('OCPPServiceUtils.isConnectorIdValid', async () => {
+    await it('should return true for connector ID greater than zero', () => {
+      const result = OCPPServiceUtils.isConnectorIdValid(
+        makeStationStub(),
+        IncomingRequestCommand.REMOTE_START_TRANSACTION,
+        1
+      )
+      expect(result).toBe(true)
+    })
+
+    await it('should return true for connector ID zero', () => {
+      const result = OCPPServiceUtils.isConnectorIdValid(
+        makeStationStub(),
+        IncomingRequestCommand.REMOTE_START_TRANSACTION,
+        0
+      )
+      expect(result).toBe(true)
+    })
+
+    await it('should return false for negative connector ID', () => {
+      const result = OCPPServiceUtils.isConnectorIdValid(
+        makeStationStub(),
+        IncomingRequestCommand.REMOTE_START_TRANSACTION,
+        -1
+      )
+      expect(result).toBe(false)
+    })
+  })
+})