@memberjunction/unit-testing

Utilities and mocks for writing unit tests in the MemberJunction monorepo using Vitest.

Installation

npm install --save-dev @memberjunction/unit-testing
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This package is typically already included as a dev dependency in MemberJunction projects.

Overview

This package provides helper functions and mock utilities to simplify unit testing of MemberJunction components. It handles common testing challenges like:

• Singleton reset - Clean state between tests
• Entity mocking - Mock BaseEntity behavior without database
• RunView mocking - Mock data loading operations
• Custom matchers - Additional Vitest assertions

Utilities

Singleton Reset

MemberJunction uses singletons for engines and global state. Reset them between tests to ensure isolation.

resetMJSingletons()

Clears ALL MJ singleton instances from the global store.

import { describe, it, beforeEach } from 'vitest';
import { resetMJSingletons } from '@memberjunction/unit-testing';

describe('MyEngine', () => {
  beforeEach(() => {
    resetMJSingletons(); // Clean slate for each test
  });

  it('should create fresh engine instance', () => {
    const engine = MyEngine.Instance; // Gets new instance
    // ... test
  });
});
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resetClassFactory()

Resets only the ClassFactory registrations. Lighter weight than resetMJSingletons.

import { resetClassFactory } from '@memberjunction/unit-testing';

beforeEach(() => {
  resetClassFactory(); // Only reset class registrations
});
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resetObjectCache()

Clears the global object cache used by MJ for caching data.

import { resetObjectCache } from '@memberjunction/unit-testing';

beforeEach(() => {
  resetObjectCache(); // Clear cached objects
});
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Entity Mocking

createMockEntity<T>(data, options?)

Creates a Proxy-based mock that behaves like a BaseEntity with getter/setter properties.

Why needed: BaseEntity uses getters/setters, so the spread operator (...entity) doesn't work. This mock provides the same interface without requiring a real database.

import { createMockEntity } from '@memberjunction/unit-testing';

// Create a mock user entity
const mockUser = createMockEntity({
  ID: 'user-123',
  Name: 'Test User',
  Email: 'test@example.com',
  Status: 'Active'
});

// Use like a real entity
console.log(mockUser.Name); // 'Test User'
mockUser.Status = 'Inactive'; // Setter works
console.log(mockUser.Get('Email')); // 'test@example.com'
console.log(mockUser.GetAll()); // { ID: '...', Name: '...', ... }

await mockUser.Save(); // Mock save (always succeeds)
console.log(mockUser.Dirty); // false after save
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Options:

interface MockEntityOptions {
  isSaved?: boolean;  // Default: true - Entity appears saved to DB
  isDirty?: boolean;  // Default: false - Entity appears clean
}

// Create unsaved entity
const newEntity = createMockEntity(
  { ID: '', Name: 'New User' },
  { isSaved: false, isDirty: true }
);
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Mock Entity Methods:

• Get(fieldName) - Get field value (case-insensitive)
• Set(fieldName, value) - Set field value (marks dirty)
• GetAll() - Returns all fields as plain object
• Save() - Mock save operation (always succeeds, clears dirty flag)
• Delete() - Mock delete operation (always succeeds)
• Dirty - Boolean indicating if entity has unsaved changes
• IsSaved - Boolean indicating if entity exists in DB
• PrimaryKey - Mock primary key object

RunView Mocking

mockRunView(entityName, mockResults)

Mocks a single RunView operation to return specific results.

import { mockRunView } from '@memberjunction/unit-testing';
import { vi } from 'vitest';

// Mock RunView for 'Users' entity
const mockUsers = [
  createMockEntity({ ID: '1', Name: 'Alice' }),
  createMockEntity({ ID: '2', Name: 'Bob' })
];

const runViewSpy = mockRunView('Users', mockUsers);

// Now when code calls RunView:
const rv = new RunView();
const result = await rv.RunView({ EntityName: 'Users' });
// result.Results === mockUsers

// Verify it was called
expect(runViewSpy).toHaveBeenCalledWith(
  expect.objectContaining({ EntityName: 'Users' })
);
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mockRunViews(mocks)

Mocks multiple RunView operations at once.

import { mockRunViews } from '@memberjunction/unit-testing';

mockRunViews({
  'Users': mockUsers,
  'Actions': mockActions,
  'AI Models': mockModels
});

// All three entities will return mock data
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resetRunViewMocks()

Clears all RunView mocks.

import { resetRunViewMocks } from '@memberjunction/unit-testing';

afterEach(() => {
  resetRunViewMocks(); // Clean up mocks
});
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Custom Matchers

installCustomMatchers()

Installs additional Vitest matchers for MemberJunction-specific assertions.

import { installCustomMatchers } from '@memberjunction/unit-testing';
import { beforeAll } from 'vitest';

beforeAll(() => {
  installCustomMatchers();
});

// Now use custom matchers in your tests
// (See vitest.d.ts for available custom matchers)
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Common Patterns

Test Structure with Full Setup

import { describe, it, expect, beforeEach } from 'vitest';
import {
  resetMJSingletons,
  createMockEntity,
  mockRunView
} from '@memberjunction/unit-testing';

describe('MyService', () => {
  beforeEach(() => {
    // Reset singletons for clean state
    resetMJSingletons();
  });

  it('should process users correctly', async () => {
    // Setup mock data
    const mockUsers = [
      createMockEntity({ ID: '1', Name: 'Alice', Status: 'Active' }),
      createMockEntity({ ID: '2', Name: 'Bob', Status: 'Inactive' })
    ];

    // Mock RunView to return mock data
    mockRunView('Users', mockUsers);

    // Test your service
    const service = new MyService();
    const result = await service.getActiveUsers();

    // Assertions
    expect(result).toHaveLength(1);
    expect(result[0].Name).toBe('Alice');
  });
});
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Mocking Entity Creation

When testing code that creates entities via Metadata.GetEntityObject():

import { vi } from 'vitest';
import { createMockEntity } from '@memberjunction/unit-testing';

// Mock the Metadata class
vi.mock('@memberjunction/core', () => ({
  Metadata: vi.fn(function() {
    return {
      GetEntityObject: vi.fn(async (entityName) => {
        return createMockEntity({ ID: '', Name: '' }, { isSaved: false });
      })
    };
  })
}));
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Testing Singleton Engines

import { resetMJSingletons } from '@memberjunction/unit-testing';

describe('ActionEngine', () => {
  beforeEach(() => {
    resetMJSingletons(); // Ensures fresh instance
  });

  it('should load actions', async () => {
    const engine = ActionEngine.Instance;
    await engine.Load();
    expect(engine.Actions.length).toBeGreaterThan(0);
  });

  it('should get separate instance after reset', async () => {
    const engine1 = ActionEngine.Instance;
    resetMJSingletons();
    const engine2 = ActionEngine.Instance;

    expect(engine1).not.toBe(engine2); // Different instances
  });
});
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TypeScript Support

This package includes TypeScript definitions for all utilities. Import types as needed:

import type { MockEntityOptions, MockEntityMethods } from '@memberjunction/unit-testing';
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Best Practices

DO:

• ✅ Always reset singletons in beforeEach() for test isolation
• ✅ Use createMockEntity() instead of plain objects for BaseEntity mocks
• ✅ Use mockRunView() to avoid database dependencies in unit tests
• ✅ Keep mocks simple and focused on the test case

DON'T:

• ❌ Share mock data between tests (creates hidden dependencies)
• ❌ Forget to reset singletons (causes test interference)
• ❌ Over-mock (test real logic where possible)
• ❌ Use real database connections in unit tests (use integration tests instead)

Related Documentation

• Testing Strategy: See /unit-testing/README.md for comprehensive testing guidelines
• Analytics: See /unit-testing/README.md for test reporting and analytics
• Integration Tests: See /packages/TestingFramework/ for full-stack testing

Examples

Look at existing tests for usage examples:

• /packages/MJCore/src/__tests__/ - Core functionality tests
• /packages/Actions/Engine/src/__tests__/ - Action engine tests
• /packages/AI/*/src/__tests__/ - AI provider tests

Contributing

When adding new test utilities:

1. Add the utility function to appropriate file (singleton-reset.ts, mock-entity.ts, etc.)
2. Export from index.ts
3. Update this README with usage examples
4. Add TypeScript definitions to vitest.d.ts if adding custom matchers

License

See repository root LICENSE file.