pulsar/spec/module-cache-spec.js

const path = require('path');
const Module = require('module');
const fs = require('fs-plus');
const temp = require('temp').track();
const ModuleCache = require('../src/module-cache');

describe('ModuleCache', function() {
  beforeEach(() => spyOn(Module, '_findPath').andCallThrough());

  afterEach(function() {
    try {
      temp.cleanupSync();
    } catch (error) {}
  });

  it('resolves Electron module paths without hitting the filesystem', function() {
    const { builtins } = ModuleCache.cache;
    expect(Object.keys(builtins).length).toBeGreaterThan(0);

    for (let builtinName in builtins) {
      const builtinPath = builtins[builtinName];
      expect(require.resolve(builtinName)).toBe(builtinPath);
      expect(fs.isFileSync(require.resolve(builtinName))).toBeTruthy();
    }

    expect(Module._findPath.callCount).toBe(0);
  });

  it('resolves relative core paths without hitting the filesystem', function() {
    ModuleCache.add(atom.getLoadSettings().resourcePath, {
      _atomModuleCache: {
        extensions: {
          '.json': [path.join('spec', 'fixtures', 'module-cache', 'file.json')]
        }
      }
    });
    expect(require('./fixtures/module-cache/file.json').foo).toBe('bar');
    expect(Module._findPath.callCount).toBe(0);
  });

  it('resolves module paths when a compatible version is provided by core', function() {
    const packagePath = fs.realpathSync(temp.mkdirSync('atom-package'));
    ModuleCache.add(packagePath, {
      _atomModuleCache: {
        folders: [
          {
            paths: [''],
            dependencies: {
              'underscore-plus': '*'
            }
          }
        ]
      }
    });
    ModuleCache.add(atom.getLoadSettings().resourcePath, {
      _atomModuleCache: {
        dependencies: [
          {
            name: 'underscore-plus',
            version: require('underscore-plus/package.json').version,
            path: path.join(
              'node_modules',
              'underscore-plus',
              'lib',
              'underscore-plus.js'
            )
          }
        ]
      }
    });

    const indexPath = path.join(packagePath, 'index.js');
    fs.writeFileSync(
      indexPath,
      `\
exports.load = function() { require('underscore-plus'); };\
`
    );

    const packageMain = require(indexPath);
    Module._findPath.reset();
    packageMain.load();
    expect(Module._findPath.callCount).toBe(0);
  });

  it('does not resolve module paths when no compatible version is provided by core', function() {
    const packagePath = fs.realpathSync(temp.mkdirSync('atom-package'));
    ModuleCache.add(packagePath, {
      _atomModuleCache: {
        folders: [
          {
            paths: [''],
            dependencies: {
              'underscore-plus': '0.0.1'
            }
          }
        ]
      }
    });
    ModuleCache.add(atom.getLoadSettings().resourcePath, {
      _atomModuleCache: {
        dependencies: [
          {
            name: 'underscore-plus',
            version: require('underscore-plus/package.json').version,
            path: path.join(
              'node_modules',
              'underscore-plus',
              'lib',
              'underscore-plus.js'
            )
          }
        ]
      }
    });

    const indexPath = path.join(packagePath, 'index.js');
    fs.writeFileSync(
      indexPath,
      `\
exports.load = function() { require('underscore-plus'); };\
`
    );

    spyOn(process, 'cwd').andReturn('/'); // Required when running this test from CLI
    const packageMain = require(indexPath);
    Module._findPath.reset();
    expect(() => packageMain.load()).toThrow();
    expect(Module._findPath.callCount).toBe(1);
  });
});