refactor(node resolve): clean codebase and fix external warnings

packages/node-resolve/README.md

@@ -44,118 +44,106 @@ Then call `rollup` either via the [CLI](https://www.rollupjs.org/guide/en/#comma
 
 ## Options
 
-### `mainFields`
+### `browser`
 
-Type: `Array[...String]`<br>
-Default: `['module', 'main']`<br>
-Valid values: `['browser', 'jsnext', 'module', 'main']`
+Type: `Boolean`<br>
+Default: `false`
 
-Specifies the properties to scan within a `package.json`, used to determine the bundle entry point. The order of property names is significant, as the first-found property is used as the resolved entry point. If the array contains `'browser'`, key/values specified in the `package.json` `browser` property will be used.
+If `true`, instructs the plugin to use the `"browser"` property in `package.json` files to specify alternative files to load for bundling. This is useful when bundling for a browser environment. Alternatively, a value of `'browser'` can be added to the `mainFields` option. If `false`, any `"browser"` properties in package files will be ignored. This option takes precedence over `mainFields`.
 
-### `module`
+### `customResolveOptions`
 
-DEPRECATED: use "mainFields" instead
+Type: `Boolean`<br>
+Default: `null`
 
-Use `pkg.module` field for ES6 module if possible. This option takes precedence over both "jsnext" and "main" in the list if such are present.
+An `Object` that specifies additional options that should be passed through to `node-resolve`.
 
-### `jsnext`
+```
+customResolveOptions: {
+  moduleDirectory: 'js_modules'
+}
+```
 
-DEPRECATED: use "mainFields" instead
+### `dedupe`
 
-Use `pkg['jsnext:main']` if possible, legacy field pointing to ES6 module in third-party libraries, deprecated in favor of `pkg.module`, see: https://github.com/rollup/rollup/wiki/pkg.module. This option takes precedence over "main" in the list if such is present.
+Type: `Array[...String]`<br>
+Default: `[]`
 
-### `main`
+An `Array` of modules names, which instructs the plugin to force resolving for the specified modules to the root `node_modules`. Helps to prevent bundling the same package multiple times if package is imported from dependencies.
 
-DEPRECATED: use "mainFields" instead
+```js
+dedupe: ['my-package', '@namespace/my-package'];
+```
 
-Use `pkg.main` field or index.js, even if it's not an ES6 module (needs to be converted from CommonJS to ES6), see https://github.com/rollup/rollup-plugin-commonjs.
+This will deduplicate bare imports such as:
 
-### `browser`
+```js
+import 'my-package';
+import '@namespace/my-package';
+```
 
-Type: `Boolean`<br>
-Default: `false`
+And it will deduplicate deep imports such as:
 
-If `true`, instructs the plugin to use the `"browser"` property in `package.json` files to specify alternative files to load for bundling. This is useful when bundling for a browser environment. Alternatively, a value of `'browser'` can be added to the `mainFields` option. If `false`, any `"browser"` properties in package files will be ignored. This option takes precedence over `mainFields`.
+```js
+import 'my-package/foo.js';
+import '@namespace/my-package/bar.js';
+```
 
 ### `extensions`
 
 Type: `Array[...String]`<br>
 Default: `['.mjs', '.js', '.json', '.node']`
 
-Resolve extensions other than .js in the order specified.
-
-### `preferBuiltins`
-
-Type: `Boolean`<br>
-Default: `true`
-
-Whether to prefer built-in modules (e.g. `fs`, `path`) or local ones with the same names
+Specifies the extensions of files that the plugin will operate on.
 
 ### `jail`
 
 Type: `String`<br>
 Default: `'/'`
 
-Lock the module search in this path (like a chroot). Modules defined outside this path will be marked as external.
-
-### `only`
-
-Type: `Array[...String|RegExp]`<br>
-Default: `null`
+Locks the module search within specified path (e.g. chroot). Modules defined outside this path will be marked as external.
 
-Example: `only: ['some_module', /^@some_scope\/.*$/]`
+### `mainFields`
 
-### `modulesOnly`
+Type: `Array[...String]`<br>
+Default: `['module', 'main']`<br>
+Valid values: `['browser', 'jsnext', 'module', 'main']`
 
-Type: `Boolean`<br>
-Default: `false`
+Specifies the properties to scan within a `package.json`, used to determine the bundle entry point. The order of property names is significant, as the first-found property is used as the resolved entry point. If the array contains `'browser'`, key/values specified in the `package.json` `browser` property will be used.
 
-If true, inspect resolved files to check that they are ES2015 modules.
+### `only`
 
-### `dedupe`
+DEPRECATED: use "resolveOnly" instead
 
-Type: `Array[...String]`<br>
-Default: `[]`
+### `preferBuiltins`
 
-Force resolving for these modules to root's node_modules that helps to prevent bundling the same package multiple times if package is imported from dependencies.
+Type: `Boolean`<br>
+Default: `true`
 
-```
-dedupe: [ 'my-package', '@namespace/my-package' ]
-```
+If `true`, the plugin will prefer built-in modules (e.g. `fs`, `path`). If `false`, the plugin will look for locally installed modules of the same name.
 
-This will deduplicate bare imports such as:
+### `modulesOnly`
 
-```js
-import 'my-package';
-import '@namespace/my-package';
-```
+Type: `Boolean`<br>
+Default: `false`
 
-And it will deduplicate deep imports such as:
+If `true`, inspect resolved files to assert that they are ES2015 modules.
 
-```js
-import 'my-package/foo.js';
-import '@namespace/my-package/bar.js';
-```
-
-### `customResolveOptions`
+### `resolveOnly`
 
-Type: `Boolean`<br>
+Type: `Array[...String|RegExp]`<br>
 Default: `null`
 
-Any additional options that should be passed through to node-resolve.
+An `Array` which instructs the plugin to limit module resolution to those whose names match patterns in the array. _Note: Modules not matching any patterns will be marked as external._
 
-```
-customResolveOptions: {
-  moduleDirectory: 'js_modules'
-}
-```
+Example: `resolveOnly: ['batman', /^@batcave\/.*$/]`
 
 ### `rootDir`
 
 Type: `String`<br>
 Default: `process.cwd()`
 
-Root directory to resolve modules from. Used when resolving entrypoint imports, and when resolving deduplicated modules. Useful when executing rollup in a package of a monorepository.
+Specifies the root directory from which to resolve modules. Typically used when resolving entry-point imports, and when resolving deduplicated modules. Useful when executing rollup in a package of a mono-repository.
 
 ```
 // Set the root directory to be the parent folder
@@ -184,7 +172,7 @@ export default {
 
 ## Resolving Built-Ins (like `fs`)
 
-This plugin won't resolve any builtins (e.g. `fs`). If you need to resolve builtins you can install local modules and set `preferBuiltins` to `false`, or install a plugin like [rollup-plugin-node-builtins](https://github.com/calvinmetcalf/rollup-plugin-node-builtins) which provides stubbed versions of these methods.
+This plugin won't resolve any builtins (e.g. `fs`). If you need to resolve builtins you can install local modules and set `preferBuiltins` to `false`, or install a plugin like [rollup-plugin-node-polyfills](https://github.com/ionic-team/rollup-plugin-node-polyfills) which provides stubbed versions of these methods.
 
 If you want to silence warnings about builtins, you can add the list of builtins to the `externals` option; like so:
 

packages/node-resolve/package.json

@@ -48,20 +48,20 @@
     "rollup": "^1.20.0"
   },
   "dependencies": {
-    "@rollup/pluginutils": "^3.0.0",
+    "@rollup/pluginutils": "^3.0.6",
     "@types/resolve": "0.0.8",
     "builtin-modules": "^3.1.0",
     "is-module": "^1.0.0",
-    "resolve": "^1.11.1"
+    "resolve": "^1.14.2"
   },
   "devDependencies": {
-    "@babel/core": "^7.4.5",
-    "@babel/preset-env": "^7.4.5",
-    "@rollup/plugin-json": "^4.0.0",
-    "es5-ext": "^0.10.50",
-    "rollup": "^1.20.0",
-    "rollup-plugin-babel": "^4.3.2",
-    "rollup-plugin-commonjs": "^10.0.0",
+    "@babel/core": "^7.8.3",
+    "@babel/preset-env": "^7.8.3",
+    "@rollup/plugin-json": "^4.0.1",
+    "es5-ext": "^0.10.53",
+    "rollup": "^1.29.0",
+    "rollup-plugin-babel": "^4.3.3",
+    "rollup-plugin-commonjs": "^10.1.0",
     "source-map": "^0.7.3",
     "string-capitalize": "^1.0.1"
   },

packages/node-resolve/rollup.config.js

@@ -20,7 +20,7 @@ export default {
       ]
     })
   ],
-  external: Object.keys(pkg.dependencies).concat(['path', 'fs', 'os']),
+  external: Object.keys(pkg.dependencies).concat(['fs', 'path', 'os', 'util']),
   output: [
     { file: pkg.main, format: 'cjs' },
     { file: pkg.module, format: 'es' }

packages/node-resolve/src/cache.js

@@ -0,0 +1,55 @@
+import { readFile, stat } from './fs';
+
+const onError = (error) => {
+  if (error.code === 'ENOENT') {
+    return false;
+  }
+  throw error;
+};
+
+const makeCache = (fn) => {
+  const cache = new Map();
+  const wrapped = async (param, done) => {
+    if (cache.has(param) === false) {
+      cache.set(
+        param,
+        fn(param).catch((err) => {
+          cache.delete(param);
+          throw err;
+        })
+      );
+    }
+
+    try {
+      const result = cache.get(param);
+      const value = await result;
+      return done(null, value);
+    } catch (error) {
+      return done(error);
+    }
+  };
+
+  wrapped.clear = () => cache.clear();
+
+  return wrapped;
+};
+
+export const isDirCached = makeCache(async (file) => {
+  try {
+    const stats = await stat(file);
+    return stats.isDirectory();
+  } catch (error) {
+    return onError(error);
+  }
+});
+
+export const isFileCached = makeCache(async (file) => {
+  try {
+    const stats = await stat(file);
+    return stats.isFile();
+  } catch (error) {
+    return onError(error);
+  }
+});
+
+export const readCachedFile = makeCache(readFile);

packages/node-resolve/src/fs.js

@@ -0,0 +1,9 @@
+import fs from 'fs';
+
+import { promisify } from 'util';
+
+export const exists = promisify(fs.exists);
+export const readFile = promisify(fs.readFile);
+export const realpath = promisify(fs.realpath);
+export { realpathSync } from 'fs';
+export const stat = promisify(fs.stat);