Test Creation and Running Skill

This skill provides guidance for creating and running tests in the Markco VS Code extension.

Project Test Structure

code

src/test/
├── runTest.ts           # Test runner entry point
└── suite/
    ├── index.ts         # Mocha test suite loader
    ├── CommentService.test.ts    # CommentService unit tests
    ├── CommentDecorator.test.ts  # CommentDecorator unit tests
    └── extension.test.ts         # Integration tests

Running Tests

From Command Line

bash

# Run all tests
npm run test

# Compile and run tests
npm run test:watch

# Just compile (prerequisite for tests)
npm run compile

From VS Code

•Task Runner: Press Ctrl+Shift+P → "Tasks: Run Task" → Select "Run Tests"
•Debug Tests: Press F5 → Select "Run Extension Tests"
•Quick Test: Ctrl+Shift+B to compile, then Ctrl+Shift+P → "Tasks: Run Test Task"

Writing New Tests

Test File Template

typescript

import * as assert from 'assert';
import * as vscode from 'vscode';
import * as sinon from 'sinon';
import * as Mocha from 'mocha';

const suite = Mocha.suite;
const test = Mocha.test;
const setup = Mocha.setup;
const teardown = Mocha.teardown;

suite('YourComponent Test Suite', () => {
  let sandbox: sinon.SinonSandbox;

  setup(() => {
    sandbox = sinon.createSandbox();
  });

  teardown(() => {
    sandbox.restore();
  });

  suite('Feature Group', () => {
    test('should do something', () => {
      // Arrange
      const expected = 'value';
      
      // Act
      const actual = 'value';
      
      // Assert
      assert.strictEqual(actual, expected);
    });
  });
});

Mock Document Helper

Mock documents require the encoding property:

typescript

function createMockDocument(text: string): vscode.TextDocument {
  const lines = text.split('\n');
  return {
    uri: vscode.Uri.parse('file:///test/mock.md'),
    languageId: 'markdown',
    lineCount: lines.length,
    encoding: 'utf-8',  // Required!
    getText: (range?: vscode.Range) => range ? /* extract range */ : text,
    // ... other required properties
  } as vscode.TextDocument;
}

Mock Editor for Integration Tests

typescript

async function createMockEditor(text: string): Promise<vscode.TextEditor> {
  const document = await vscode.workspace.openTextDocument({
    language: 'markdown',
    content: text
  });
  return await vscode.window.showTextDocument(document);
}

Test Categories

Unit Tests

•Test individual functions in isolation
•Mock VS Code APIs
•Focus on business logic
•Located in: CommentService.test.ts, CommentDecorator.test.ts

Integration Tests

•Test component interactions
•Use real VS Code APIs when possible
•Test command execution
•Located in: extension.test.ts

Key Test Scenarios to Cover

CommentService

•Parse comments from markdown
•Handle malformed JSON
•Ignore comment blocks in code fences
•CRUD operations on comments
•Reply management
•Anchor reconciliation
•Text sanitization (-->)

CommentDecorator

•Apply/clear decorations
•Find comment at position
•Focus management
•Navigate to comment

Extension

•Command registration
•Activation events
•Configuration handling
•Webview communication

Mocking Tips

Stub VS Code APIs

typescript

sandbox.stub(vscode.window, 'showInformationMessage').resolves();
sandbox.stub(vscode.workspace, 'applyEdit').resolves(true);

Stub Git Commands

typescript

sandbox.stub(child_process, 'exec').yields(null, { stdout: 'testuser\n' });

Common Issues

•Tests hang: Ensure all async operations complete
•Extension not active: Tests run in separate VS Code instance
•File not found: Use absolute paths or mock documents
•Mocha functions undefined: Must import from Mocha explicitly (see template above)

Adding New Test File

•Create src/test/suite/NewComponent.test.ts
•Follow the test template above (with Mocha imports!)
•Run npm run compile
•Run npm test