stop using esm for ES module loading

.eslintignore

@@ -1,2 +1,3 @@
 /node_modules
 /tmp
+/lib/esm/import.js

.eslintrc

@@ -1,3 +1,3 @@
 {
-  "extends": "groupon/node8"
+  "extends": "groupon/node10"
 }

.travis.yml

@@ -1,13 +1,14 @@
 language: node_js
 node_js:
-  - '8'
   - '10'
+  - '12'
+env:
+  - NODE_OPTIONS=
+  - NODE_OPTIONS=--experimental-modules
 deploy:
   - provider: script
-    script: ./node_modules/.bin/nlm release
+    script: npx nlm release
     skip_cleanup: true
     'on':
       branch: master
-      node: '10'
-before_install:
-  - npm i -g npm@^6
+      node: '12'

README.md

@@ -122,6 +122,11 @@ This function returns an array with one entry for each interface file:
   relative to the app's root directory.
 * `group`: The directory the file was found in.
 
+Note that `.mjs` file support requires you to be using a version of node with
+builtin support for ES Modules.  Currently this is Node 10+ with
+the `--experimental-modules` flag.  Node 10.x seems to experience
+segfaults under certain conditions, so we recommend 12+.
+
 ### Registry
 
 A set of three scopes, in order of nesting:

lib/esm/import.js

@@ -0,0 +1,40 @@
+/*
+ * Copyright (c) 2019, Groupon
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * Redistributions of source code must retain the above copyright notice,
+ * this list of conditions and the following disclaimer.
+ *
+ * Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ *
+ * Neither the name of GROUPON nor the names of its contributors may be
+ * used to endorse or promote products derived from this software without
+ * specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS
+ * IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
+ * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A
+ * PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED
+ * TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
+ * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
+ * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
+ * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+ * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+'use strict';
+
+// put this in its own file so that it can barf on require if needed
+
+/**
+ * @param {string} id
+ * @returns {Promise<any>}
+ */
+module.exports = id => import(id);

lib/esm/index.js

@@ -0,0 +1,48 @@
+/*
+ * Copyright (c) 2019, Groupon
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * Redistributions of source code must retain the above copyright notice,
+ * this list of conditions and the following disclaimer.
+ *
+ * Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ *
+ * Neither the name of GROUPON nor the names of its contributors may be
+ * used to endorse or promote products derived from this software without
+ * specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS
+ * IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
+ * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A
+ * PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED
+ * TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
+ * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
+ * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
+ * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+ * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+'use strict';
+
+const debug = require('debug')('esm');
+
+/** @type {(id: string) => Promise<any>} */
+let importESM;
+try {
+  importESM = require('./import');
+} catch (err) {
+  debug('failed to load esm import: ', err);
+  importESM = () => Promise.reject(new Error('Not supported'));
+}
+
+exports.importESM = importESM;
+exports.supportsESM = () =>
+  importESM('../../package.json').then(() => true, () => false);

lib/project.js

@@ -33,42 +33,33 @@
 'use strict';
 
 const path = require('path');
-const Module = require('module');
+// @ts-ignore
+const { createRequireFromPath, createRequire } = require('module');
 const util = require('util');
+const { URL } = require('url');
 
 const debug = require('debug')('nilo:project');
 // @ts-ignore
-const esm = require('esm');
-// @ts-ignore
 const globCallback = require('glob');
 
 const glob = util.promisify(globCallback);
 
-// @ts-ignore
-const rawModulePaths = Module['_nodeModulePaths'];
-const getModulePaths = /** @type {(from: string) => string[]} */ (rawModulePaths);
+// createRequireFromPath is deprecated Node 10.x; createRequire is official 12+
+/** @type {typeof createRequireFromPath} */
+const createReq = createRequire || createRequireFromPath;
+
+const { importESM } = require('./esm');
 
 /**
- * @typedef {import('./typedefs').InterfaceFile} InterfaceFile
+ * @param {string} reSTR
  */
+function escapeRE(reSTR) {
+  return reSTR.replace(/[$^*()+\[\]{}\\|.?]/g, '\\$&');
+}
 
 /**
- * @param {object} esmResult
- * @param {string} specifier
+ * @typedef {import('./typedefs').InterfaceFile} InterfaceFile
  */
-function guessNamespace(esmResult, specifier) {
-  if (specifier.endsWith('.mjs')) return esmResult;
-
-  // "Heuristic" to figure out if it kinda looks like a namespace
-  if (
-    esmResult !== null &&
-    typeof esmResult === 'object' &&
-    'default' in esmResult
-  )
-    return esmResult;
-
-  return { default: esmResult };
-}
 
 class Project {
   /**
@@ -79,39 +70,20 @@ class Project {
     this.root = appDirectory;
 
     const appPath = path.resolve(appDirectory, 'app');
-    this.app = new Module('<app>');
-    this.app.filename = appPath;
-    this.app.paths = getModulePaths(appPath);
+    this.require = createReq(appPath);
 
     const frameworkPath = path.resolve(frameworkDirectory, 'app');
-    this.framework = new Module('<framework>');
-    this.framework.filename = frameworkPath;
-    this.framework.paths = getModulePaths(frameworkPath);
+    this.requireBundled = createReq(frameworkPath);
 
     this._pkgJson = null;
     this._globCache = {};
     this._globStatCache = {};
-
-    this._importESM = esm(this.app, {
-      cjs: {
-        cache: false,
-        esModule: false,
-        extensions: false,
-        mutableNamespace: false,
-        namedExports: false,
-        paths: false,
-        vars: false,
-        dedefault: false,
-        topLevelReturn: false,
-      },
-      mode: 'strict',
-    });
   }
 
   /**
    * @param {string} pattern
    * @param {object} [options]
-   * @returns {string[]}
+   * @returns {Promise<string[]>}
    */
   cachedGlob(pattern, options = {}) {
     return glob(
@@ -188,9 +160,22 @@ class Project {
    * @param {string} id
    * @returns {Promise<unknown>}
    */
-  import(id) {
-    const esmResult = this._importESM(id);
-    return guessNamespace(esmResult, id);
+  async import(id) {
+    debug('import', id);
+    // if it's a package spec, assume we can't load it as a ES module
+    // for now
+    if (!/^(\.\.?)?\//.test(id)) return { default: this.require(id) };
+
+    try {
+      return await importESM(
+        /^\.\.?\//.test(id)
+          ? new URL(id, `file://${this.root}/app`).toString()
+          : id
+      );
+    } catch (err) {
+      if (err.message !== 'Not supported') throw err;
+      return { default: this.require(id) };
+    }
   }
 
   /**
@@ -204,21 +189,13 @@ class Project {
       // Still throw errors unrelated to finding the module
       if (e.code !== 'MODULE_NOT_FOUND') throw e;
       // Do *not* ignore failing requires of subsequent files
-      if (!e.message.includes(`'${id}'`)) throw e;
+      const re = new RegExp(`(^|[\\s'"])${escapeRE(id)}([\\s'"]|$)`);
+      if (!re.test(e.message)) throw e;
 
       return null;
     }
   }
 
-  /**
-   * @template T
-   * @param {string} id
-   * @returns {T}
-   */
-  require(id) {
-    return this.app.require(id);
-  }
-
   /**
    * @template T
    * @param {string} id
@@ -237,15 +214,6 @@ class Project {
     }
   }
 
-  /**
-   * @template T
-   * @param {string} id
-   * @returns {T}
-   */
-  requireBundled(id) {
-    return this.framework.require(id);
-  }
-
   /**
    * @template T
    * @param {string} id

lib/registry/injector.js

@@ -41,15 +41,7 @@ const { parseDependencyQuery } = require('./query');
 /** @typedef {import('../typedefs').DependencyDescriptor} DependencyDescriptor */
 /** @typedef {import('../typedefs').DependencyQuery} DependencyQuery */
 
-const INSPECT = util.inspect.custom || Symbol.for('nodejs.util.inspect.custom');
-
-/**
- * @param {Injector} injector
- */
-function inspectProvider(injector) {
-  // @ts-ignore
-  return `Provider { ${injector[INSPECT]()} }`;
-}
+const INSPECT = util.inspect.custom;
 
 const PROVIDER_HANDLER = {
   /**
@@ -59,17 +51,14 @@ const PROVIDER_HANDLER = {
   get(injector, key) {
     switch (key) {
       case 'constructor':
-        return injector.constructor;
-
       case 'get':
-        return injector.get;
-
       case 'keys':
-        return injector.keys;
+      case 'scope':
+        return injector[key];
 
-      case INSPECT: {
-        return inspectProvider.bind(null, injector);
-      }
+      case INSPECT:
+        // @ts-ignore
+        return injector[INSPECT];
 
       default:
         return injector.get(key);

package.json

@@ -28,7 +28,6 @@
   "dependencies": {
     "commander": "^2.19.0",
     "debug": "^4.1.1",
-    "esm": "^3.2.20",
     "glob": "^7.1.3"
   },
   "devDependencies": {