module: add findPackageJSON util

PR-URL: #55412
Reviewed-By: Matteo Collina <matteo.collina@gmail.com>
Reviewed-By: Antoine du Hamel <duhamelantoine1995@gmail.com>

Author: JakobJingleheimer

doc/api/module.md

@@ -217,6 +217,88 @@ added: v22.8.0
 * Returns: {string|undefined} Path to the [module compile cache][] directory if it is enabled,
  or `undefined` otherwise.
 
+### `module.findPackageJSON(specifier[, base])`
+
+<!-- YAML
+added: REPLACEME
+-->
+
+> Stability: 1.1 - Active Development
+
+* `specifier` {string|URL} The specifier for the module whose `package.json` to
+ retrieve. When passing a _bare specifier_, the `package.json` at the root of
+ the package is returned. When passing a _relative specifier_ or an _absolute specifier_,
+ the closest parent `package.json` is returned.
+* `base` {string|URL} The absolute location (`file:` URL string or FS path) of the
+ containing module. For CJS, use `__filename` (not `__dirname`!); for ESM, use
+`import.meta.url`. You do not need to pass it if `specifier` is an `absolute specifier`.
+* Returns: {string|undefined} A path if the `package.json` is found. When `startLocation`
+ is a package, the package's root `package.json`; when a relative or unresolved, the closest
+`package.json` to the `startLocation`.
+
+> **Caveat**: Do not use this to try to determine module format. There are many things effecting
+> that determination; the `type` field of package.json is the _least_ definitive (ex file extension
+> superceeds it, and a loader hook superceeds that).
+
+```text
+/path/to/project
+ ├ packages/
+ ├ bar/
+ ├ bar.js
+ └ package.json// name = '@foo/bar'
+ └ qux/
+ ├ node_modules/
+ └ some-package/
+ └ package.json// name = 'some-package'
+ ├ qux.js
+ └ package.json// name = '@foo/qux'
+ ├ main.js
+ └ package.json// name = '@foo'
+```
+
+```mjs
+// /path/to/project/packages/bar/bar.js
+import { findPackageJSON } from'node:module';
+
+findPackageJSON('..', import.meta.url);
+// '/path/to/project/package.json'
+// Same result when passing an absolute specifier instead:
+findPackageJSON(newURL('../', import.meta.url));
+findPackageJSON(import.meta.resolve('../'));
+
+findPackageJSON('some-package', import.meta.url);
+// '/path/to/project/packages/bar/node_modules/some-package/package.json'
+// When passing an absolute specifier, you might get a different result if the
+// resolved module is inside a subfolder that has nested `package.json`.
+findPackageJSON(import.meta.resolve('some-package'));
+// '/path/to/project/packages/bar/node_modules/some-package/some-subfolder/package.json'
+
+findPackageJSON('@foo/qux', import.meta.url);
+// '/path/to/project/packages/qux/package.json'
+```
+
+```cjs
+// /path/to/project/packages/bar/bar.js
+const { findPackageJSON } =require('node:module');
+const { pathToFileURL } =require('node:url');
+constpath=require('node:path');
+
+findPackageJSON('..', __filename);
+// '/path/to/project/package.json'
+// Same result when passing an absolute specifier instead:
+findPackageJSON(pathToFileURL(path.join(__dirname, '..')));
+
+findPackageJSON('some-package', __filename);
+// '/path/to/project/packages/bar/node_modules/some-package/package.json'
+// When passing an absolute specifier, you might get a different result if the
+// resolved module is inside a subfolder that has nested `package.json`.
+findPackageJSON(pathToFileURL(require.resolve('some-package')));
+// '/path/to/project/packages/bar/node_modules/some-package/some-subfolder/package.json'
+
+findPackageJSON('@foo/qux', __filename);
+// '/path/to/project/packages/qux/package.json'
+```
+
 ### `module.isBuiltin(moduleName)`
 
 <!-- YAML

lib/internal/modules/cjs/loader.js

@@ -602,11 +602,11 @@ function trySelf(parentPath, request) {
 try{
 const{ packageExportsResolve }=require('internal/modules/esm/resolve');
 returnfinalizeEsmResolution(packageExportsResolve(
-pathToFileURL(pkg.path+'/package.json'),expansion,pkg.data,
+pathToFileURL(pkg.path),expansion,pkg.data,
 pathToFileURL(parentPath),getCjsConditions()),parentPath,pkg.path);
 }catch(e){
 if(e.code==='ERR_MODULE_NOT_FOUND'){
-throwcreateEsmNotFoundErr(request,pkg.path+'/package.json');
+throwcreateEsmNotFoundErr(request,pkg.path);
 }
 throwe;
 }
@@ -1201,14 +1201,15 @@ Module._resolveFilename = function(request, parent, isMain, options) {
 
 if(request[0]==='#'&&(parent?.filename||parent?.id==='<repl>')){
 constparentPath=parent?.filename??process.cwd()+path.sep;
-constpkg=packageJsonReader.getNearestParentPackageJSON(parentPath)||{__proto__: null};
-if(pkg.data?.imports!=null){
+constpkg=packageJsonReader.getNearestParentPackageJSON(parentPath);
+if(pkg?.data.imports!=null){
 try{
 const{ packageImportsResolve }=require('internal/modules/esm/resolve');
 returnfinalizeEsmResolution(
-packageImportsResolve(request,pathToFileURL(parentPath),
-getCjsConditions()),parentPath,
-pkg.path);
+packageImportsResolve(request,pathToFileURL(parentPath),getCjsConditions()),
+parentPath,
+pkg.path,
+);
 }catch(e){
 if(e.code==='ERR_MODULE_NOT_FOUND'){
 throwcreateEsmNotFoundErr(request);
@@ -1268,8 +1269,7 @@ function finalizeEsmResolution(resolved, parentPath, pkgPath) {
 if(actual){
 returnactual;
 }
-consterr=createEsmNotFoundErr(filename,
-path.resolve(pkgPath,'package.json'));
+consterr=createEsmNotFoundErr(filename,pkgPath);
 throwerr;
 }
 
@@ -1623,7 +1623,7 @@ function loadTS(module, filename) {
 
 constparent=module[kModuleParent];
 constparentPath=parent?.filename;
-constpackageJsonPath=path.resolve(pkg.path,'package.json');
+constpackageJsonPath=pkg.path;
 constusesEsm=containsModuleSyntax(content,filename);
 consterr=newERR_REQUIRE_ESM(filename,usesEsm,parentPath,
 packageJsonPath);
@@ -1682,7 +1682,7 @@ Module._extensions['.js'] = function(module, filename) {
 // This is an error path because `require` of a `.js` file in a `"type": "module"` scope is not allowed.
 constparent=module[kModuleParent];
 constparentPath=parent?.filename;
-constpackageJsonPath=path.resolve(pkg.path,'package.json');
+constpackageJsonPath=pkg.path;
 constusesEsm=containsModuleSyntax(content,filename);
 consterr=newERR_REQUIRE_ESM(filename,usesEsm,parentPath,
 packageJsonPath);

lib/internal/modules/esm/resolve.js

@@ -356,7 +356,6 @@ function invalidPackageTarget(
 
 constinvalidSegmentRegEx=/(^|\\|\/)((\.|%2e)(\.|%2e)?|(n|%6e|%4e)(o|%6f|%4f)(d|%64|%44)(e|%65|%45)(_|%5f)(m|%6d|%4d)(o|%6f|%4f)(d|%64|%44)(u|%75|%55)(l|%6c|%4c)(e|%65|%45)(s|%73|%53))?(\\|\/|$)/i;
 constdeprecatedInvalidSegmentRegEx=/(^|\\|\/)((\.|%2e)(\.|%2e)?|(n|%6e|%4e)(o|%6f|%4f)(d|%64|%44)(e|%65|%45)(_|%5f)(m|%6d|%4d)(o|%6f|%4f)(d|%64|%44)(u|%75|%55)(l|%6c|%4c)(e|%65|%45)(s|%73|%53))(\\|\/|$)/i;
-constinvalidPackageNameRegEx=/^\.|%|\\/;
 constpatternRegEx=/\*/g;
 
 /**
@@ -752,44 +751,6 @@ function packageImportsResolve(name, base, conditions) {
 throwimportNotDefined(name,packageJSONUrl,base);
 }
 
-/**
- * Parse a package name from a specifier.
- * @param {string} specifier - The import specifier.
- * @param {string | URL | undefined} base - The parent URL.
- */
-functionparsePackageName(specifier,base){
-letseparatorIndex=StringPrototypeIndexOf(specifier,'/');
-letvalidPackageName=true;
-letisScoped=false;
-if(specifier[0]==='@'){
-isScoped=true;
-if(separatorIndex===-1||specifier.length===0){
-validPackageName=false;
-}else{
-separatorIndex=StringPrototypeIndexOf(
-specifier,'/',separatorIndex+1);
-}
-}
-
-constpackageName=separatorIndex===-1 ?
-specifier : StringPrototypeSlice(specifier,0,separatorIndex);
-
-// Package name cannot have leading . and cannot have percent-encoding or
-// \\ separators.
-if(RegExpPrototypeExec(invalidPackageNameRegEx,packageName)!==null){
-validPackageName=false;
-}
-
-if(!validPackageName){
-thrownewERR_INVALID_MODULE_SPECIFIER(
-specifier,'is not a valid package name',fileURLToPath(base));
-}
-
-constpackageSubpath='.'+(separatorIndex===-1 ? '' :
-StringPrototypeSlice(specifier,separatorIndex));
-
-return{ packageName, packageSubpath, isScoped };
-}
 
 /**
  * Resolves a package specifier to a URL.
@@ -804,57 +765,24 @@ function packageResolve(specifier, base, conditions) {
 returnnewURL('node:'+specifier);
 }
 
-const{ packageName, packageSubpath, isScoped }=
-parsePackageName(specifier,base);
+const{ packageJSONUrl, packageJSONPath, packageSubpath }=packageJsonReader.getPackageJSONURL(specifier,base);
 
-// ResolveSelf
-constpackageConfig=packageJsonReader.getPackageScopeConfig(base);
-if(packageConfig.exists){
-if(packageConfig.exports!=null&&packageConfig.name===packageName){
-constpackageJSONUrl=pathToFileURL(packageConfig.pjsonPath);
-returnpackageExportsResolve(
-packageJSONUrl,packageSubpath,packageConfig,base,conditions);
-}
-}
+constpackageConfig=packageJsonReader.read(packageJSONPath,{__proto__: null, specifier, base,isESM: true});
 
-letpackageJSONUrl=
-newURL('./node_modules/'+packageName+'/package.json',base);
-letpackageJSONPath=fileURLToPath(packageJSONUrl);
-letlastPath;
-do{
-conststat=internalFsBinding.internalModuleStat(
-internalFsBinding,
-StringPrototypeSlice(packageJSONPath,0,packageJSONPath.length-13),
+// Package match.
+if(packageConfig.exports!=null){
+returnpackageExportsResolve(
+packageJSONUrl,packageSubpath,packageConfig,base,conditions);
+}
+if(packageSubpath==='.'){
+returnlegacyMainResolve(
+packageJSONUrl,
+packageConfig,
+base,
 );
-// Check for !stat.isDirectory()
-if(stat!==1){
-lastPath=packageJSONPath;
-packageJSONUrl=newURL((isScoped ?
-'../../../../node_modules/' : '../../../node_modules/')+
-packageName+'/package.json',packageJSONUrl);
-packageJSONPath=fileURLToPath(packageJSONUrl);
-continue;
-}
-
-// Package match.
-constpackageConfig=packageJsonReader.read(packageJSONPath,{__proto__: null, specifier, base,isESM: true});
-if(packageConfig.exports!=null){
-returnpackageExportsResolve(
-packageJSONUrl,packageSubpath,packageConfig,base,conditions);
-}
-if(packageSubpath==='.'){
-returnlegacyMainResolve(
-packageJSONUrl,
-packageConfig,
-base,
-);
-}
-
-returnnewURL(packageSubpath,packageJSONUrl);
-// Cross-platform root check.
-}while(packageJSONPath.length!==lastPath.length);
+}
 
-thrownewERR_MODULE_NOT_FOUND(packageName,fileURLToPath(base),null);
+returnnewURL(packageSubpath,packageJSONUrl);
 }
 
 /**
@@ -1105,10 +1033,11 @@ module.exports = {
  decorateErrorWithCommonJSHints,
  defaultResolve,
  encodedSepRegEx,
+ legacyMainResolve,
  packageExportsResolve,
  packageImportsResolve,
+ packageResolve,
  throwIfInvalidParentURL,
- legacyMainResolve,
 };
 
 // cycle