From e312d60e3f81dfa26d5922f3c23a371b2b2ce343 Mon Sep 17 00:00:00 2001
From: Jacob Smith <3012099+JakobJingleheimer@users.noreply.github.com>
Date: Fri, 25 Oct 2024 22:40:54 +0200
Subject: [PATCH] module: add `findPackageJSON` util

PR-URL: https://github.com/nodejs/node/pull/55412
Reviewed-By: Matteo Collina <matteo.collina@gmail.com>
Reviewed-By: Antoine du Hamel <duhamelantoine1995@gmail.com>
---
 doc/api/module.md                             |  82 ++++++
 lib/internal/modules/cjs/loader.js            |  22 +-
 lib/internal/modules/esm/resolve.js           | 103 ++-----
 lib/internal/modules/package_json_reader.js   | 265 ++++++++++++++----
 lib/module.js                                 |   7 +-
 .../packages/cjs-main-no-index/main.js        |   1 +
 .../packages/cjs-main-no-index/other.js       |   3 +
 .../packages/cjs-main-no-index/package.json   |   5 +
 test/fixtures/packages/nested/package.json    |   1 +
 .../packages/nested/sub-pkg-cjs/index.js      |   3 +
 .../packages/nested/sub-pkg-cjs/package.json  |   1 +
 .../packages/nested/sub-pkg-esm/index.js      |   3 +
 .../packages/nested/sub-pkg-esm/package.json  |   1 +
 .../packages/root-types-field/index.js        |   0
 .../packages/root-types-field/package.json    |   5 +
 test/parallel/test-find-package-json.js       | 152 ++++++++++
 typings/internalBinding/modules.d.ts          |  13 +-
 17 files changed, 516 insertions(+), 151 deletions(-)
 create mode 100644 test/fixtures/packages/cjs-main-no-index/main.js
 create mode 100644 test/fixtures/packages/cjs-main-no-index/other.js
 create mode 100644 test/fixtures/packages/cjs-main-no-index/package.json
 create mode 100644 test/fixtures/packages/nested/package.json
 create mode 100644 test/fixtures/packages/nested/sub-pkg-cjs/index.js
 create mode 100644 test/fixtures/packages/nested/sub-pkg-cjs/package.json
 create mode 100644 test/fixtures/packages/nested/sub-pkg-esm/index.js
 create mode 100644 test/fixtures/packages/nested/sub-pkg-esm/package.json
 create mode 100644 test/fixtures/packages/root-types-field/index.js
 create mode 100644 test/fixtures/packages/root-types-field/package.json
 create mode 100644 test/parallel/test-find-package-json.js

diff --git a/doc/api/module.md b/doc/api/module.md
index 8662cc218898d5..5ead40d6da3fe0 100644
--- a/doc/api/module.md
+++ b/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(new URL('../', 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');
+const path = 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
diff --git a/lib/internal/modules/cjs/loader.js b/lib/internal/modules/cjs/loader.js
index af37c2511200da..20d06d7ebed21a 100644
--- a/lib/internal/modules/cjs/loader.js
+++ b/lib/internal/modules/cjs/loader.js
@@ -602,11 +602,11 @@ function trySelf(parentPath, request) {
   try {
     const { packageExportsResolve } = require('internal/modules/esm/resolve');
     return finalizeEsmResolution(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') {
-      throw createEsmNotFoundErr(request, pkg.path + '/package.json');
+      throw createEsmNotFoundErr(request, pkg.path);
     }
     throw e;
   }
@@ -1201,14 +1201,15 @@ Module._resolveFilename = function(request, parent, isMain, options) {
 
   if (request[0] === '#' && (parent?.filename || parent?.id === '<repl>')) {
     const parentPath = parent?.filename ?? process.cwd() + path.sep;
-    const pkg = packageJsonReader.getNearestParentPackageJSON(parentPath) || { __proto__: null };
-    if (pkg.data?.imports != null) {
+    const pkg = packageJsonReader.getNearestParentPackageJSON(parentPath);
+    if (pkg?.data.imports != null) {
       try {
         const { packageImportsResolve } = require('internal/modules/esm/resolve');
         return finalizeEsmResolution(
-          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') {
           throw createEsmNotFoundErr(request);
@@ -1268,8 +1269,7 @@ function finalizeEsmResolution(resolved, parentPath, pkgPath) {
   if (actual) {
     return actual;
   }
-  const err = createEsmNotFoundErr(filename,
-                                   path.resolve(pkgPath, 'package.json'));
+  const err = createEsmNotFoundErr(filename, pkgPath);
   throw err;
 }
 
@@ -1623,7 +1623,7 @@ function loadTS(module, filename) {
 
     const parent = module[kModuleParent];
     const parentPath = parent?.filename;
-    const packageJsonPath = path.resolve(pkg.path, 'package.json');
+    const packageJsonPath = pkg.path;
     const usesEsm = containsModuleSyntax(content, filename);
     const err = new ERR_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.
       const parent = module[kModuleParent];
       const parentPath = parent?.filename;
-      const packageJsonPath = path.resolve(pkg.path, 'package.json');
+      const packageJsonPath = pkg.path;
       const usesEsm = containsModuleSyntax(content, filename);
       const err = new ERR_REQUIRE_ESM(filename, usesEsm, parentPath,
                                       packageJsonPath);
diff --git a/lib/internal/modules/esm/resolve.js b/lib/internal/modules/esm/resolve.js
index 61c043e35c6ce9..bfd9bd3d127404 100644
--- a/lib/internal/modules/esm/resolve.js
+++ b/lib/internal/modules/esm/resolve.js
@@ -356,7 +356,6 @@ function invalidPackageTarget(
 
 const invalidSegmentRegEx = /(^|\\|\/)((\.|%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))?(\\|\/|$)/i;
 const deprecatedInvalidSegmentRegEx = /(^|\\|\/)((\.|%2e)(\.|%2e)?|(n|%6e|%4e)(o|%6f|%4f)(d|%64|%44)(e|%65|%45)(_|%5f)(m|%6d|%4d)(o|%6f|%4f)(d|%64|%44)(u|%75|%55)(l|%6c|%4c)(e|%65|%45)(s|%73|%53))(\\|\/|$)/i;
-const invalidPackageNameRegEx = /^\.|%|\\/;
 const patternRegEx = /\*/g;
 
 /**
@@ -752,44 +751,6 @@ function packageImportsResolve(name, base, conditions) {
   throw importNotDefined(name, packageJSONUrl, base);
 }
 
-/**
- * Parse a package name from a specifier.
- * @param {string} specifier - The import specifier.
- * @param {string | URL | undefined} base - The parent URL.
- */
-function parsePackageName(specifier, base) {
-  let separatorIndex = StringPrototypeIndexOf(specifier, '/');
-  let validPackageName = true;
-  let isScoped = false;
-  if (specifier[0] === '@') {
-    isScoped = true;
-    if (separatorIndex === -1 || specifier.length === 0) {
-      validPackageName = false;
-    } else {
-      separatorIndex = StringPrototypeIndexOf(
-        specifier, '/', separatorIndex + 1);
-    }
-  }
-
-  const packageName = 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) {
-    throw new ERR_INVALID_MODULE_SPECIFIER(
-      specifier, 'is not a valid package name', fileURLToPath(base));
-  }
-
-  const packageSubpath = '.' + (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) {
     return new URL('node:' + specifier);
   }
 
-  const { packageName, packageSubpath, isScoped } =
-    parsePackageName(specifier, base);
+  const { packageJSONUrl, packageJSONPath, packageSubpath } = packageJsonReader.getPackageJSONURL(specifier, base);
 
-  // ResolveSelf
-  const packageConfig = packageJsonReader.getPackageScopeConfig(base);
-  if (packageConfig.exists) {
-    if (packageConfig.exports != null && packageConfig.name === packageName) {
-      const packageJSONUrl = pathToFileURL(packageConfig.pjsonPath);
-      return packageExportsResolve(
-        packageJSONUrl, packageSubpath, packageConfig, base, conditions);
-    }
-  }
+  const packageConfig = packageJsonReader.read(packageJSONPath, { __proto__: null, specifier, base, isESM: true });
 
-  let packageJSONUrl =
-    new URL('./node_modules/' + packageName + '/package.json', base);
-  let packageJSONPath = fileURLToPath(packageJSONUrl);
-  let lastPath;
-  do {
-    const stat = internalFsBinding.internalModuleStat(
-      internalFsBinding,
-      StringPrototypeSlice(packageJSONPath, 0, packageJSONPath.length - 13),
+  // Package match.
+  if (packageConfig.exports != null) {
+    return packageExportsResolve(
+      packageJSONUrl, packageSubpath, packageConfig, base, conditions);
+  }
+  if (packageSubpath === '.') {
+    return legacyMainResolve(
+      packageJSONUrl,
+      packageConfig,
+      base,
     );
-    // Check for !stat.isDirectory()
-    if (stat !== 1) {
-      lastPath = packageJSONPath;
-      packageJSONUrl = new URL((isScoped ?
-        '../../../../node_modules/' : '../../../node_modules/') +
-        packageName + '/package.json', packageJSONUrl);
-      packageJSONPath = fileURLToPath(packageJSONUrl);
-      continue;
-    }
-
-    // Package match.
-    const packageConfig = packageJsonReader.read(packageJSONPath, { __proto__: null, specifier, base, isESM: true });
-    if (packageConfig.exports != null) {
-      return packageExportsResolve(
-        packageJSONUrl, packageSubpath, packageConfig, base, conditions);
-    }
-    if (packageSubpath === '.') {
-      return legacyMainResolve(
-        packageJSONUrl,
-        packageConfig,
-        base,
-      );
-    }
-
-    return new URL(packageSubpath, packageJSONUrl);
-    // Cross-platform root check.
-  } while (packageJSONPath.length !== lastPath.length);
+  }
 
-  throw new ERR_MODULE_NOT_FOUND(packageName, fileURLToPath(base), null);
+  return new URL(packageSubpath, packageJSONUrl);
 }
 
 /**
@@ -1105,10 +1033,11 @@ module.exports = {
   decorateErrorWithCommonJSHints,
   defaultResolve,
   encodedSepRegEx,
+  legacyMainResolve,
   packageExportsResolve,
   packageImportsResolve,
+  packageResolve,
   throwIfInvalidParentURL,
-  legacyMainResolve,
 };
 
 // cycle
diff --git a/lib/internal/modules/package_json_reader.js b/lib/internal/modules/package_json_reader.js
index 9a9dcebb799c00..d55ccbad64d0e6 100644
--- a/lib/internal/modules/package_json_reader.js
+++ b/lib/internal/modules/package_json_reader.js
@@ -4,29 +4,54 @@ const {
   ArrayIsArray,
   JSONParse,
   ObjectDefineProperty,
-  StringPrototypeLastIndexOf,
+  RegExpPrototypeExec,
+  StringPrototypeIndexOf,
   StringPrototypeSlice,
+  StringPrototypeStartsWith,
 } = primordials;
-const modulesBinding = internalBinding('modules');
-const { resolve, sep } = require('path');
+const {
+  fileURLToPath,
+  isURL,
+  pathToFileURL,
+  URL,
+} = require('internal/url');
+const { canParse: URLCanParse } = internalBinding('url');
+const {
+  codes: {
+    ERR_INVALID_MODULE_SPECIFIER,
+    ERR_MISSING_ARGS,
+    ERR_MODULE_NOT_FOUND,
+  },
+} = require('internal/errors');
 const { kEmptyObject } = require('internal/util');
+const modulesBinding = internalBinding('modules');
+const path = require('path');
+const { validateString } = require('internal/validators');
+const internalFsBinding = internalBinding('fs');
 
 /**
- * @param {string} path
- * @param {import('typings/internalBinding/modules').SerializedPackageConfig} contents
- * @returns {import('typings/internalBinding/modules').PackageConfig}
+ * @typedef {import('typings/internalBinding/modules').DeserializedPackageConfig} DeserializedPackageConfig
+ * @typedef {import('typings/internalBinding/modules').PackageConfig} PackageConfig
+ * @typedef {import('typings/internalBinding/modules').SerializedPackageConfig} SerializedPackageConfig
+ */
+
+/**
+ * @param {URL['pathname']} path
+ * @param {SerializedPackageConfig} contents
+ * @returns {DeserializedPackageConfig}
  */
 function deserializePackageJSON(path, contents) {
   if (contents === undefined) {
     return {
-      __proto__: null,
+      data: {
+        __proto__: null,
+        type: 'none', // Ignore unknown types for forwards compatibility
+      },
       exists: false,
-      pjsonPath: path,
-      type: 'none', // Ignore unknown types for forwards compatibility
+      path,
     };
   }
 
-  let pjsonPath = path;
   const {
     0: name,
     1: main,
@@ -36,37 +61,40 @@ function deserializePackageJSON(path, contents) {
     5: optionalFilePath,
   } = contents;
 
-  // This is required to be used in getPackageScopeConfig.
-  if (optionalFilePath) {
-    pjsonPath = optionalFilePath;
-  }
-
-  // The imports and exports fields can be either undefined or a string.
-  // - If it's a string, it's either plain string or a stringified JSON string.
-  // - If it's a stringified JSON string, it starts with either '[' or '{'.
-  const requiresJSONParse = (value) => (value !== undefined && (value[0] === '[' || value[0] === '{'));
+  const pjsonPath = optionalFilePath ?? path;
 
   return {
-    __proto__: null,
-    exists: true,
-    pjsonPath,
-    name,
-    main,
-    type,
-    // This getters are used to lazily parse the imports and exports fields.
-    get imports() {
-      const value = requiresJSONParse(plainImports) ? JSONParse(plainImports) : plainImports;
-      ObjectDefineProperty(this, 'imports', { __proto__: null, value });
-      return this.imports;
-    },
-    get exports() {
-      const value = requiresJSONParse(plainExports) ? JSONParse(plainExports) : plainExports;
-      ObjectDefineProperty(this, 'exports', { __proto__: null, value });
-      return this.exports;
+    data: {
+      __proto__: null,
+      ...(name != null && { name }),
+      ...(main != null && { main }),
+      ...(type != null && { type }),
+      ...(plainImports != null && {
+        // This getters are used to lazily parse the imports and exports fields.
+        get imports() {
+          const value = requiresJSONParse(plainImports) ? JSONParse(plainImports) : plainImports;
+          ObjectDefineProperty(this, 'imports', { __proto__: null, value });
+          return this.imports;
+        },
+      }),
+      ...(plainExports != null && {
+        get exports() {
+          const value = requiresJSONParse(plainExports) ? JSONParse(plainExports) : plainExports;
+          ObjectDefineProperty(this, 'exports', { __proto__: null, value });
+          return this.exports;
+        },
+      }),
     },
+    exists: true,
+    path: pjsonPath,
   };
 }
 
+// The imports and exports fields can be either undefined or a string.
+// - If it's a string, it's either plain string or a stringified JSON string.
+// - If it's a stringified JSON string, it starts with either '[' or '{'.
+const requiresJSONParse = (value) => (value !== undefined && (value[0] === '[' || value[0] === '{'));
+
 /**
  * Reads a package.json file and returns the parsed contents.
  * @param {string} jsonPath
@@ -75,7 +103,7 @@ function deserializePackageJSON(path, contents) {
  *   specifier?: URL | string,
  *   isESM?: boolean,
  * }} options
- * @returns {import('typings/internalBinding/modules').PackageConfig}
+ * @returns {PackageConfig}
  */
 function read(jsonPath, { base, specifier, isESM } = kEmptyObject) {
   // This function will be called by both CJS and ESM, so we need to make sure
@@ -87,7 +115,14 @@ function read(jsonPath, { base, specifier, isESM } = kEmptyObject) {
     specifier == null ? undefined : `${specifier}`,
   );
 
-  return deserializePackageJSON(jsonPath, parsed);
+  const result = deserializePackageJSON(jsonPath, parsed);
+
+  return {
+    __proto__: null,
+    ...result.data,
+    exists: result.exists,
+    pjsonPath: result.path,
+  };
 }
 
 /**
@@ -98,14 +133,14 @@ function read(jsonPath, { base, specifier, isESM } = kEmptyObject) {
  */
 function readPackage(requestPath) {
   // TODO(@anonrig): Remove this function.
-  return read(resolve(requestPath, 'package.json'));
+  return read(path.resolve(requestPath, 'package.json'));
 }
 
 /**
  * Get the nearest parent package.json file from a given path.
  * Return the package.json data and the path to the package.json file, or undefined.
  * @param {string} checkPath The path to start searching from.
- * @returns {undefined | {data: import('typings/internalBinding/modules').PackageConfig, path: string}}
+ * @returns {undefined | DeserializedPackageConfig}
  */
 function getNearestParentPackageJSON(checkPath) {
   const result = modulesBinding.getNearestParentPackageJSON(checkPath);
@@ -114,13 +149,7 @@ function getNearestParentPackageJSON(checkPath) {
     return undefined;
   }
 
-  const data = deserializePackageJSON(checkPath, result);
-
-  // Path should be the root folder of the matched package.json
-  // For example for ~/path/package.json, it should be ~/path
-  const path = StringPrototypeSlice(data.pjsonPath, 0, StringPrototypeLastIndexOf(data.pjsonPath, sep));
-
-  return { data, path };
+  return deserializePackageJSON(checkPath, result);
 }
 
 /**
@@ -132,7 +161,14 @@ function getPackageScopeConfig(resolved) {
   const result = modulesBinding.getPackageScopeConfig(`${resolved}`);
 
   if (ArrayIsArray(result)) {
-    return deserializePackageJSON(`${resolved}`, result);
+    const { data, exists, path } = deserializePackageJSON(`${resolved}`, result);
+
+    return {
+      __proto__: null,
+      ...data,
+      exists,
+      pjsonPath: path,
+    };
   }
 
   // This means that the response is a string
@@ -154,10 +190,145 @@ function getPackageType(url) {
   return getPackageScopeConfig(url).type;
 }
 
+const invalidPackageNameRegEx = /^\.|%|\\/;
+/**
+ * Parse a package name from a specifier.
+ * @param {string} specifier - The import specifier.
+ * @param {string | URL | undefined} base - The parent URL.
+ */
+function parsePackageName(specifier, base) {
+  let separatorIndex = StringPrototypeIndexOf(specifier, '/');
+  let validPackageName = true;
+  let isScoped = false;
+  if (specifier[0] === '@') {
+    isScoped = true;
+    if (separatorIndex === -1 || specifier.length === 0) {
+      validPackageName = false;
+    } else {
+      separatorIndex = StringPrototypeIndexOf(
+        specifier, '/', separatorIndex + 1);
+    }
+  }
+
+  const packageName = 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) {
+    throw new ERR_INVALID_MODULE_SPECIFIER(
+      specifier, 'is not a valid package name', fileURLToPath(base));
+  }
+
+  const packageSubpath = '.' + (separatorIndex === -1 ? '' :
+    StringPrototypeSlice(specifier, separatorIndex));
+
+  return { packageName, packageSubpath, isScoped };
+}
+
+function getPackageJSONURL(specifier, base) {
+  const { packageName, packageSubpath, isScoped } =
+    parsePackageName(specifier, base);
+
+  // ResolveSelf
+  const packageConfig = getPackageScopeConfig(base);
+  if (packageConfig.exists) {
+    if (packageConfig.exports != null && packageConfig.name === packageName) {
+      const packageJSONPath = packageConfig.pjsonPath;
+      return { packageJSONUrl: pathToFileURL(packageJSONPath), packageJSONPath, packageSubpath };
+    }
+  }
+
+  let packageJSONUrl =
+    new URL('./node_modules/' + packageName + '/package.json', base);
+  let packageJSONPath = fileURLToPath(packageJSONUrl);
+  let lastPath;
+  do {
+    const stat = internalFsBinding.internalModuleStat(
+      internalFsBinding,
+      StringPrototypeSlice(packageJSONPath, 0, packageJSONPath.length - 13),
+    );
+    // Check for !stat.isDirectory()
+    if (stat !== 1) {
+      lastPath = packageJSONPath;
+      packageJSONUrl = new URL((isScoped ?
+        '../../../../node_modules/' : '../../../node_modules/') +
+        packageName + '/package.json', packageJSONUrl);
+      packageJSONPath = fileURLToPath(packageJSONUrl);
+      continue;
+    }
+
+    // Package match.
+    return { packageJSONUrl, packageJSONPath, packageSubpath };
+  } while (packageJSONPath.length !== lastPath.length);
+
+  throw new ERR_MODULE_NOT_FOUND(packageName, fileURLToPath(base), null);
+}
+
+const pjsonImportAttributes = { __proto__: null, type: 'json' };
+let cascadedLoader;
+/**
+ * @param {URL['href'] | string | URL} specifier The location for which to get the "root" package.json
+ * @param {URL['href'] | string | URL} [base] The location of the current module (ex file://tmp/foo.js).
+ */
+function findPackageJSON(specifier, base = 'data:') {
+  if (arguments.length === 0) {
+    throw new ERR_MISSING_ARGS('specifier');
+  }
+  try {
+    specifier = `${specifier}`;
+  } catch {
+    validateString(specifier, 'specifier');
+  }
+
+  let parentURL;
+  if (isURL(base)) {
+    parentURL = new URL(base);
+  } else {
+    validateString(base, 'base');
+    if (
+      path.isAbsolute(base) ||
+      (URLCanParse(base) && !StringPrototypeStartsWith(base, 'file:'))
+    ) {
+      parentURL = pathToFileURL(path.toNamespacedPath(base));
+    } else {
+      parentURL = URL.parse(base) || pathToFileURL(base);
+    }
+  }
+
+  if (specifier && specifier[0] !== '.' && specifier[0] !== '/' && !URLCanParse(specifier)) {
+    const { packageJSONPath } = getPackageJSONURL(specifier, parentURL);
+    return packageJSONPath;
+  }
+
+  let resolvedTarget;
+  cascadedLoader ??= require('internal/modules/esm/loader').getOrInitializeCascadedLoader();
+
+  try {
+    resolvedTarget = cascadedLoader.resolve(specifier, `${parentURL}`, pjsonImportAttributes).url;
+  } catch (err) {
+    if (err.code === 'ERR_UNSUPPORTED_DIR_IMPORT') {
+      resolvedTarget = err.url;
+    } else {
+      throw err;
+    }
+  }
+
+  const pkg = getNearestParentPackageJSON(fileURLToPath(resolvedTarget));
+
+  return pkg?.path;
+}
+
 module.exports = {
   read,
   readPackage,
   getNearestParentPackageJSON,
   getPackageScopeConfig,
   getPackageType,
+  getPackageJSONURL,
+  findPackageJSON,
 };
diff --git a/lib/module.js b/lib/module.js
index eb400e71ae0400..a0317d06e0edb0 100644
--- a/lib/module.js
+++ b/lib/module.js
@@ -10,6 +10,9 @@ const {
   flushCompileCache,
   getCompileCacheDir,
 } = require('internal/modules/helpers');
+const {
+  findPackageJSON,
+} = require('internal/modules/package_json_reader');
 const { stripTypeScriptTypes } = require('internal/modules/typescript');
 
 Module.findSourceMap = findSourceMap;
@@ -17,7 +20,9 @@ Module.register = register;
 Module.SourceMap = SourceMap;
 Module.constants = constants;
 Module.enableCompileCache = enableCompileCache;
+Module.findPackageJSON = findPackageJSON;
 Module.flushCompileCache = flushCompileCache;
-Module.stripTypeScriptTypes = stripTypeScriptTypes;
 Module.getCompileCacheDir = getCompileCacheDir;
+Module.stripTypeScriptTypes = stripTypeScriptTypes;
+
 module.exports = Module;
diff --git a/test/fixtures/packages/cjs-main-no-index/main.js b/test/fixtures/packages/cjs-main-no-index/main.js
new file mode 100644
index 00000000000000..888cae37af95c5
--- /dev/null
+++ b/test/fixtures/packages/cjs-main-no-index/main.js
@@ -0,0 +1 @@
+module.exports = 42;
diff --git a/test/fixtures/packages/cjs-main-no-index/other.js b/test/fixtures/packages/cjs-main-no-index/other.js
new file mode 100644
index 00000000000000..8fa48276783484
--- /dev/null
+++ b/test/fixtures/packages/cjs-main-no-index/other.js
@@ -0,0 +1,3 @@
+const answer = require('./');
+
+module.exports = answer+1;
diff --git a/test/fixtures/packages/cjs-main-no-index/package.json b/test/fixtures/packages/cjs-main-no-index/package.json
new file mode 100644
index 00000000000000..897d3f99daf7a2
--- /dev/null
+++ b/test/fixtures/packages/cjs-main-no-index/package.json
@@ -0,0 +1,5 @@
+{
+  "name": "main-no-index",
+  "main": "./main.js",
+  "type":"commonjs"
+}
diff --git a/test/fixtures/packages/nested/package.json b/test/fixtures/packages/nested/package.json
new file mode 100644
index 00000000000000..0ce6c71db42e8c
--- /dev/null
+++ b/test/fixtures/packages/nested/package.json
@@ -0,0 +1 @@
+{"name": "package-with-sub-package"}
diff --git a/test/fixtures/packages/nested/sub-pkg-cjs/index.js b/test/fixtures/packages/nested/sub-pkg-cjs/index.js
new file mode 100644
index 00000000000000..679ad2d65ed570
--- /dev/null
+++ b/test/fixtures/packages/nested/sub-pkg-cjs/index.js
@@ -0,0 +1,3 @@
+const { findPackageJSON } = require('node:module');
+
+module.exports = findPackageJSON('..', __filename);
diff --git a/test/fixtures/packages/nested/sub-pkg-cjs/package.json b/test/fixtures/packages/nested/sub-pkg-cjs/package.json
new file mode 100644
index 00000000000000..2dec7591cd6db8
--- /dev/null
+++ b/test/fixtures/packages/nested/sub-pkg-cjs/package.json
@@ -0,0 +1 @@
+{"name": "sub-package", "type": "commonjs"}
diff --git a/test/fixtures/packages/nested/sub-pkg-esm/index.js b/test/fixtures/packages/nested/sub-pkg-esm/index.js
new file mode 100644
index 00000000000000..546390de4bf3a5
--- /dev/null
+++ b/test/fixtures/packages/nested/sub-pkg-esm/index.js
@@ -0,0 +1,3 @@
+import { findPackageJSON } from 'node:module';
+
+export default findPackageJSON('..', import.meta.url);
diff --git a/test/fixtures/packages/nested/sub-pkg-esm/package.json b/test/fixtures/packages/nested/sub-pkg-esm/package.json
new file mode 100644
index 00000000000000..c294ec5158824a
--- /dev/null
+++ b/test/fixtures/packages/nested/sub-pkg-esm/package.json
@@ -0,0 +1 @@
+{"name": "sub-package", "type": "module"}
diff --git a/test/fixtures/packages/root-types-field/index.js b/test/fixtures/packages/root-types-field/index.js
new file mode 100644
index 00000000000000..e69de29bb2d1d6
diff --git a/test/fixtures/packages/root-types-field/package.json b/test/fixtures/packages/root-types-field/package.json
new file mode 100644
index 00000000000000..4af68442446dd8
--- /dev/null
+++ b/test/fixtures/packages/root-types-field/package.json
@@ -0,0 +1,5 @@
+{
+  "name": "package-with-unrecognised-fields",
+  "type": "module",
+  "types": "./index.d.ts"
+}
diff --git a/test/parallel/test-find-package-json.js b/test/parallel/test-find-package-json.js
new file mode 100644
index 00000000000000..cc74b46c031aa1
--- /dev/null
+++ b/test/parallel/test-find-package-json.js
@@ -0,0 +1,152 @@
+'use strict';
+
+const common = require('../common');
+const fixtures = require('../common/fixtures');
+const tmpdir = require('../common/tmpdir');
+const assert = require('node:assert');
+const fs = require('node:fs');
+const { findPackageJSON } = require('node:module');
+const path = require('node:path');
+const { describe, it } = require('node:test');
+
+
+describe('findPackageJSON', () => { // Throws when no arguments are provided
+  it('should throw when no arguments are provided', () => {
+    assert.throws(
+      () => findPackageJSON(),
+      { code: 'ERR_MISSING_ARGS' }
+    );
+  });
+
+  it('should throw when parentLocation is invalid', () => {
+    for (const invalid of [null, {}, [], Symbol(), () => {}, true, false, 1, 0]) {
+      assert.throws(
+        () => findPackageJSON('', invalid),
+        { code: 'ERR_INVALID_ARG_TYPE' },
+      );
+    }
+  });
+
+  it('should accept a file URL (string), like from `import.meta.resolve()`', () => {
+    const importMetaUrl = `${fixtures.fileURL('whatever.ext')}`;
+    const specifierBase = './packages/root-types-field';
+    assert.strictEqual(
+      findPackageJSON(`${specifierBase}/index.js`, importMetaUrl),
+      path.toNamespacedPath(fixtures.path(specifierBase, 'package.json')),
+    );
+  });
+
+  it('should accept a file URL instance', () => {
+    const importMetaUrl = fixtures.fileURL('whatever.ext');
+    const specifierBase = './packages/root-types-field';
+    assert.strictEqual(
+      findPackageJSON(
+        new URL(`${specifierBase}/index.js`, importMetaUrl),
+        importMetaUrl,
+      ),
+      path.toNamespacedPath(fixtures.path(specifierBase, 'package.json')),
+    );
+  });
+
+  it('should be able to crawl up (CJS)', () => {
+    const pathToMod = fixtures.path('packages/nested/sub-pkg-cjs/index.js');
+    const parentPkg = require(pathToMod);
+
+    const pathToParent = path.toNamespacedPath(fixtures.path('packages/nested/package.json'));
+    assert.strictEqual(parentPkg, pathToParent);
+  });
+
+  it('should be able to crawl up (ESM)', () => {
+    const pathToMod = fixtures.path('packages/nested/sub-pkg-esm/index.js');
+    const parentPkg = require(pathToMod).default; // This test is a CJS file
+
+    const pathToParent = path.toNamespacedPath(fixtures.path('packages/nested/package.json'));
+    assert.strictEqual(parentPkg, pathToParent);
+  });
+
+  it('can require via package.json', () => {
+    const pathToMod = fixtures.path('packages/cjs-main-no-index/other.js');
+    // `require()` falls back to package.json values like "main" to resolve when there is no index
+    const answer = require(pathToMod);
+
+    assert.strictEqual(answer, 43);
+  });
+
+  it('should be able to resolve both root and closest package.json', () => {
+    tmpdir.refresh();
+
+    fs.writeFileSync(tmpdir.resolve('entry.mjs'), `
+      import { findPackageJSON } from 'node:module';
+      import fs from 'node:fs';
+
+      const readPJSON = (locus) => JSON.parse(fs.readFileSync(locus, 'utf8'));
+
+      const { secretNumberPkgRoot } = readPJSON(findPackageJSON('pkg', import.meta.url));
+      const { secretNumberSubfolder } = readPJSON(findPackageJSON(import.meta.resolve('pkg')));
+      const { secretNumberSubfolder2 } = readPJSON(findPackageJSON(import.meta.resolve('pkg2')));
+      const { secretNumberPkg2 } = readPJSON(findPackageJSON('pkg2', import.meta.url));
+
+      console.log(secretNumberPkgRoot, secretNumberSubfolder, secretNumberSubfolder2, secretNumberPkg2);
+    `);
+
+    const secretNumberPkgRoot = Math.ceil(Math.random() * 999);
+    const secretNumberSubfolder = Math.ceil(Math.random() * 999);
+    const secretNumberSubfolder2 = Math.ceil(Math.random() * 999);
+    const secretNumberPkg2 = Math.ceil(Math.random() * 999);
+
+    fs.mkdirSync(tmpdir.resolve('node_modules/pkg/subfolder'), { recursive: true });
+    fs.writeFileSync(
+      tmpdir.resolve('node_modules/pkg/subfolder/index.js'),
+      '',
+    );
+    fs.writeFileSync(
+      tmpdir.resolve('node_modules/pkg/subfolder/package.json'),
+      JSON.stringify({
+        type: 'module',
+        secretNumberSubfolder,
+      }),
+    );
+    fs.writeFileSync(
+      tmpdir.resolve('node_modules/pkg/package.json'),
+      JSON.stringify({
+        name: 'pkg',
+        exports: './subfolder/index.js',
+        secretNumberPkgRoot,
+      }),
+    );
+
+    fs.mkdirSync(tmpdir.resolve('node_modules/pkg/subfolder2'));
+    fs.writeFileSync(
+      tmpdir.resolve('node_modules/pkg/subfolder2/package.json'),
+      JSON.stringify({
+        type: 'module',
+        secretNumberSubfolder2,
+      }),
+    );
+    fs.writeFileSync(
+      tmpdir.resolve('node_modules/pkg/subfolder2/index.js'),
+      '',
+    );
+
+    fs.mkdirSync(tmpdir.resolve('node_modules/pkg2'));
+    fs.writeFileSync(
+      tmpdir.resolve('node_modules/pkg2/package.json'),
+      JSON.stringify({
+        name: 'pkg',
+        main: tmpdir.resolve('node_modules/pkg/subfolder2/index.js'),
+        secretNumberPkg2,
+      }),
+    );
+
+    common.spawnPromisified(process.execPath, [tmpdir.resolve('entry.mjs')]).then(common.mustCall((result) => {
+      console.error(result.stderr);
+      console.log(result.stdout);
+      assert.deepStrictEqual(result, {
+        stdout: `${secretNumberPkgRoot} ${secretNumberSubfolder} ${secretNumberSubfolder2} ${secretNumberPkg2}\n`,
+        stderr: '',
+        code: 0,
+        signal: null,
+      });
+    }));
+  });
+});
diff --git a/typings/internalBinding/modules.d.ts b/typings/internalBinding/modules.d.ts
index 8142874edfde88..7d35b864dae356 100644
--- a/typings/internalBinding/modules.d.ts
+++ b/typings/internalBinding/modules.d.ts
@@ -1,27 +1,30 @@
 export type PackageType = 'commonjs' | 'module' | 'none'
 export type PackageConfig = {
-  pjsonPath: string
-  exists: boolean
   name?: string
   main?: any
   type: PackageType
   exports?: string | string[] | Record<string, unknown>
   imports?: string | string[] | Record<string, unknown>
 }
+export type DeserializedPackageConfig = {
+  data: PackageConfig,
+  exists: boolean,
+  path: URL['pathname'],
+}
 export type SerializedPackageConfig = [
   PackageConfig['name'],
   PackageConfig['main'],
   PackageConfig['type'],
   string | undefined, // exports
   string | undefined, // imports
-  string | undefined, // raw json available for experimental policy
+  DeserializedPackageConfig['path'], // pjson file path
 ]
 
 export interface ModulesBinding {
   readPackageJSON(path: string): SerializedPackageConfig | undefined;
-  getNearestParentPackageJSON(path: string): PackageConfig | undefined
+  getNearestParentPackageJSON(path: string): SerializedPackageConfig | undefined
+  getNearestRawParentPackageJSON(origin: URL['pathname']): [ReturnType<JSON['stringify']>, DeserializedPackageConfig['path']] | undefined
   getNearestParentPackageJSONType(path: string): PackageConfig['type']
   getPackageScopeConfig(path: string): SerializedPackageConfig | undefined
   getPackageJSONScripts(): string | undefined
-  flushCompileCache(keepDeserializedCache?: boolean): void
 }