(pkg: ExtendedPackageJson)
| 46 | * Detect the module format of a package based on package.json fields |
| 47 | */ |
| 48 | export function detectModuleFormat(pkg: ExtendedPackageJson): ModuleFormat { |
| 49 | const hasExports = pkg.exports != null |
| 50 | const hasModule = !!pkg.module |
| 51 | const hasMain = !!pkg.main |
| 52 | const isTypeModule = pkg.type === 'module' |
| 53 | const isTypeCommonjs = pkg.type === 'commonjs' || !pkg.type |
| 54 | |
| 55 | // Check exports field for dual format indicators |
| 56 | if (hasExports && pkg.exports) { |
| 57 | const exportInfo = analyzeExports(pkg.exports) |
| 58 | |
| 59 | if (exportInfo.hasImport && exportInfo.hasRequire) { |
| 60 | return 'dual' |
| 61 | } |
| 62 | |
| 63 | if (exportInfo.hasImport || exportInfo.hasModule) { |
| 64 | // Has ESM exports, check if also has CJS |
| 65 | if (hasMain && !isTypeModule) { |
| 66 | return 'dual' |
| 67 | } |
| 68 | return 'esm' |
| 69 | } |
| 70 | |
| 71 | if (exportInfo.hasRequire) { |
| 72 | // Has CJS exports, check if also has ESM |
| 73 | if (hasModule) { |
| 74 | return 'dual' |
| 75 | } |
| 76 | return 'cjs' |
| 77 | } |
| 78 | |
| 79 | // exports field exists but doesn't use import/require conditions |
| 80 | // Fall through to other detection methods |
| 81 | } |
| 82 | |
| 83 | // Legacy detection without exports field |
| 84 | if (hasModule && hasMain) { |
| 85 | // Check for dual packages (has module field and main points to cjs) |
| 86 | const mainIsCJS = pkg.main?.endsWith('.cjs') || (pkg.main?.endsWith('.js') && !isTypeModule) |
| 87 | |
| 88 | return mainIsCJS ? 'dual' : 'esm' |
| 89 | } |
| 90 | |
| 91 | const mainIsWASM = pkg.main?.endsWith('.wasm') |
| 92 | if (mainIsWASM) { |
| 93 | return 'wasm' |
| 94 | } |
| 95 | |
| 96 | if (hasModule || isTypeModule) { |
| 97 | return 'esm' |
| 98 | } |
| 99 | |
| 100 | if (hasMain || isTypeCommonjs) { |
| 101 | return 'cjs' |
| 102 | } |
| 103 | |
| 104 | return 'unknown' |
| 105 | } |
no test coverage detected