import { describe, it, expect, beforeEach, afterEach } from 'vitest';
import * as path from 'path';
import { FileSystem, NodeFileSystem } from '@debugmcp/shared';
import {
isESMProject,
hasTsConfigPaths,
setDefaultFileSystem
} from '../../src/utils/config-transformer.js';
/**
* Mock implementation of FileSystem for testing
*/
class MockFileSystem implements FileSystem {
private existsMock: ((path: string) => boolean) | null = null;
private readFileMock: ((path: string, encoding: string) => string) | null = null;
setExistsMock(mock: (path: string) => boolean): void {
this.existsMock = mock;
}
setReadFileMock(mock: (path: string, encoding: string) => string): void {
this.readFileMock = mock;
}
existsSync(path: string): boolean {
if (this.existsMock) {
return this.existsMock(path);
}
return false;
}
readFileSync(path: string, encoding: string): string {
if (this.readFileMock) {
return this.readFileMock(path, encoding);
}
return '';
}
}
describe('utils/config-transformer.edge2: branch-padding cases', () => {
const projDir = path.resolve(process.cwd(), 'proj-edge2');
const programDir = path.join(projDir, 'src');
let mockFileSystem: MockFileSystem;
beforeEach(() => {
mockFileSystem = new MockFileSystem();
setDefaultFileSystem(mockFileSystem);
// Default: no files exist
mockFileSystem.setExistsMock(() => false);
mockFileSystem.setReadFileMock(() => '');
});
afterEach(() => {
// Restore the default filesystem
setDefaultFileSystem(new NodeFileSystem());
});
it('isESMProject: empty programPath uses cwd-only checks (tsconfig ESNext in cwd => true)', () => {
const tc = path.join(projDir, 'tsconfig.json');
mockFileSystem.setExistsMock((p) => String(p) === tc);
mockFileSystem.setReadFileMock((p, _enc) =>
String(p) === tc ? JSON.stringify({ compilerOptions: { module: 'ESNext' } }) : ''
);
expect(isESMProject('', projDir)).toBe(true);
});
it('isESMProject: package.json present but type not "module" does not trigger ESM', () => {
const pj = path.join(programDir, 'package.json');
mockFileSystem.setExistsMock((p) => String(p) === pj);
mockFileSystem.setReadFileMock((p, _enc) =>
String(p) === pj ? JSON.stringify({ type: 'commonjs' }) : ''
);
expect(isESMProject(path.join(programDir, 'app.js'), projDir)).toBe(false);
});
it('isESMProject: tsconfig module CommonJS does not trigger ESM', () => {
const tc = path.join(programDir, 'tsconfig.json');
mockFileSystem.setExistsMock((p) => String(p) === tc);
mockFileSystem.setReadFileMock((p, _enc) =>
String(p) === tc ? JSON.stringify({ compilerOptions: { module: 'CommonJS' } }) : ''
);
expect(isESMProject(path.join(programDir, 'app.ts'), projDir)).toBe(false);
});
it('hasTsConfigPaths: non-object paths (string/array) treated as false', () => {
const tc = path.join(projDir, 'tsconfig.json');
// Case 1: string
mockFileSystem.setExistsMock((p) => String(p) === tc);
mockFileSystem.setReadFileMock((p, _enc) =>
String(p) === tc ? JSON.stringify({ compilerOptions: { paths: 'not-an-object' } }) : ''
);
expect(hasTsConfigPaths(projDir)).toBe(false);
// Case 2: array-like — current implementation treats arrays as objects and counts keys => truthy
mockFileSystem.setReadFileMock((p, _enc) =>
String(p) === tc ? JSON.stringify({ compilerOptions: { paths: ['x'] } }) : ''
);
expect(hasTsConfigPaths(projDir)).toBe(true);
});
});
