PR: Transform Export Declarations

.eslintrc.cjs

@@ -18,6 +18,7 @@ module.exports = {
         skipWords: [
           ...RULES_SPELLCHECKER[1].skipWords,
           'callee',
+          'dirix',
           'errno',
           'filenames',
           'trext',

README.md

@@ -18,14 +18,21 @@ File extension transformer
 ## Getting Started
 
 Interested in using `.cjs` and `.mjs` file extensions, but _not_ in setting up
-another build workflow? Use `trext` to transform file extensions, import
-statements, call expressions, and even source maps!
+another build workflow? Use `trext` to transform your project's file extensions.
+Heavily inspired by [`convert-extension`][6].
 
-Heavily inspired by [`convert-extension`][5], `trext` intends to provide a more
-configurable user experience. In addition to passing custom
-[Babel transform](#babel-transform) options, maintainers can also specify custom
-[file extension search patterns](#file-extension-search-patterns) and use
-functions to [dynamically generate extensions](#dynamic-file-extensions).
+Transform file extensions in:
+
+- `export` (default and named) declarations
+- `import` declarations
+- `require` statements
+- sourcemaps
+
+In addition to file extension transformations:
+
+- Set custom [file extension search patterns](#file-extension-search-patterns)
+- Use functions to [dynamically generate extensions](#dynamic-file-extensions)
+- Pass custom [Babel transform](#babel-transform) options
 
 ## Installation
 
@@ -64,9 +71,9 @@ trext('esm/', TREXT_OPTIONS)
 
 #### Babel Transform
 
-`trext` implements a [custom Babel plugin][6] to update `import` and `require`
-statements. If enabled, source maps will also be updated. You can specify
-additional transform options using the `babel` property:
+`trext` implements a [custom Babel plugin][7] to update `export`, `import`, and
+`require` statements. If enabled, source maps will also be updated. You can
+specify additional transform options using the `babel` property:
 
 ```typescript
 import type { TrextOptions } from '@flex-development/trext'
@@ -91,22 +98,22 @@ trext('cjs/', TREXT_OPTIONS)
 
 #### Dynamic File Extensions
 
-`trext` uses the [`String.prototype.replace`][7] method to replace file
+`trext` uses the [`String.prototype.replace`][8] method to replace file
 extensions. The `to` option can also be specifed as a function to take full
 advantage of the method's capabilities. When using a function, however, note
-that **the function will also be invoked within the context of [`Trextel`][6],
+that **the function will also be invoked within the context of [`Trextel`][7],
 thus drastically changing the arguments passed to your function**:
 
 ```typescript
-import type { NodePath } from '@babel/traverse'
-import type { CallExpression, ImportDeclaration } from '@babel/types'
 import { isNode } from '@babel/types'
-import type {
+import {
   FileExtension,
+  trext,
   TrextMatch,
+  TrextNodePath,
   TrextOptions
 } from '@flex-development/trext'
-import { trext } from '@flex-development/trext'
+import Trextel from '@flex-development/trext/plugins/esm/trextel.plugin'
 import { inspect } from 'util'
 
 /**
@@ -120,16 +127,30 @@ const TREXT_OPTIONS: TrextOptions<'js', 'cjs' | 'mjs'> = {
   to(match: TrextMatch, ...args: any[]): FileExtension<'cjs' | 'mjs'> {
     // Check if match is NodePath, args === []
     if (isNode((match as any).node)) {
-      const nodePath = match as NodePath<CallExpression | ImportDeclaration>
-
-      if (nodePath.type === 'CallExpression') {
-        //
+      const nodePath = match as TrextNodePath
+      const code: string | undefined = Trextel.getCode(nodePath)
+
+      switch (nodePath.type) {
+        case 'CallExpression':
+          //
+          break
+        case 'ExportAllDeclaration':
+          //
+          break
+        case 'ExportNamedDeclaration':
+          //
+          break
+        case 'ImportDeclaration':
+          //
+          break
+        default:
+          break
       }
 
       return '.mjs'
     }
 
-    // Check is match is RegExp object
+    // Check if match is RegExp object
     if (match.constructor.name === 'RegExp') {
       const regex = match as RegExp
 
@@ -176,9 +197,10 @@ trext('esm/', TREXT_OPTIONS)
 
 #### Ignoring Directory Indexes
 
-Directory entry points are a common way of exposing a series of modules from a
-single `index.*` file. Directory index syntax allows developers to `import` and
-`require` those entries without including `/index.*` in the module specifier:
+Directory entry points are a common way of exposing a group of modules from a
+single `index.*` file. Directory index (dirix) syntax allows developers to use
+partial [import specifiers][9] (or [call expression arguments][10]) to `export`,
+`import`, or `require` those modules without including `/index.*`:
 
 ```typescript
 /**
@@ -192,11 +214,10 @@ export { default as Trext, trext, trextFile } from './plugins/trext.plugin'
 export * from './types'
 ```
 
-Specifiers `'./interfaces'` and `'./types'` use directory index syntax and
-**will be ignored** when encountered by [`Trextel`][6].
-
-By default, index lookups are performed in the `process.cwd()/src` directory.
-Set `src` to change the lookup location:
+[`Trextel`][7] searches for indexes in the `process.cwd()/src` directory. **When
+[mandatory extensions](#mandatory-file-extensions) are disabled, _partial_
+specifiers and call expression arguments are ignored**. Set `src` to change the
+directory index lookup location:
 
 ```typescript
 import type { TrextOptions } from '@flex-development/trext'
@@ -220,18 +241,81 @@ trext('cjs/', TREXT_OPTIONS)
   .catch(error => console.error(inspect(error, false, null)))
 ```
 
+#### Mandatory File Extensions
+
+`trext` forces all specifiers (and call expression arguments) to be [fully
+specified][11]. Set `mandatory` to `false` to disable transformations for all
+[`TrextNode`][12] types:
+
+```typescript
+import type { TrextOptions } from '@flex-development/trext'
+import { trext } from '@flex-development/trext'
+import { inspect } from 'util'
+
+/**
+ * @file Examples - Disabling Mandatory File Extensions
+ * @module docs/examples/mandatory
+ */
+
+const TREXT_OPTIONS: TrextOptions<'js', 'mjs'> = {
+  from: 'js',
+  mandatory: false,
+  pattern: /.js$/,
+  to: 'mjs'
+}
+
+trext('esm/', TREXT_OPTIONS)
+  .then(results => console.info(inspect(results, false, null)))
+  .catch(error => console.error(inspect(error, false, null)))
+```
+
+You can also disable transformations by [`TrextNode`][12] type:
+
+```typescript
+import type { TrextOptions } from '@flex-development/trext'
+import { trext } from '@flex-development/trext'
+import { inspect } from 'util'
+
+/**
+ * @file Examples - Disabling Mandatory File Extensions (By Node)
+ * @module docs/examples/mandatory-by-node
+ */
+
+const TREXT_OPTIONS: TrextOptions<'js', 'mjs'> = {
+  from: 'js',
+  mandatory: {
+    call: false,
+    exportAll: true,
+    exportNamed: false,
+    import: true
+  },
+  pattern: /.js$/,
+  to: 'mjs'
+}
+
+trext('mjs/', TREXT_OPTIONS)
+  .then(results => console.info(inspect(results, false, null)))
+  .catch(error => console.error(inspect(error, false, null)))
+```
+
 ## Built With
 
 - [@babel/core][1] - Babel compiler core
 - [@babel/traverse][2] - Traverse and update nodes
 - [glob][3] - Match file paths using glob patterns
 - [mkdirp][4] - Node.js implementation of `mkdir -p`
+- [path-type][5] - Check if a path is a file, directory, or symlink
 
 [1]: https://github.com/babel/babel/tree/main/packages/babel-core
 [2]: https://github.com/babel/babel/tree/main/packages/babel-traverse
 [3]: https://github.com/isaacs/node-glob
 [4]: https://github.com/isaacs/node-mkdirp
-[5]: https://github.com/peterjwest/convert-extension
-[6]: src/plugins/trextel.plugin.ts
-[7]:
+[5]: https://github.com/sindresorhus/path-type
+[6]: https://github.com/peterjwest/convert-extension
+[7]: src/plugins/trextel.plugin.ts
+[8]:
   https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/String/replace
+[9]: https://nodejs.org/api/esm.html#esm_import_specifiers
+[10]: https://babeljs.io/docs/en/babel-types#callexpression
+[11]: https://nodejs.org/api/esm.html#esm_mandatory_file_extensions
+[12]: src/types/trext-node.type.ts

__tests__/__fixtures__/hub.fixture.ts

@@ -0,0 +1,8 @@
+import { Hub } from '@babel/traverse'
+
+/**
+ * @file Test Fixture - Hub
+ * @module tests/fixtures/Hub
+ */
+
+export default new Hub()

__tests__/__fixtures__/program.fixture.ts

@@ -0,0 +1,8 @@
+import { program } from '@babel/types'
+
+/**
+ * @file Test Fixture - program
+ * @module tests/fixtures/program
+ */
+
+export default program([])

docs/examples/dynamic.example.ts

@@ -1,12 +1,12 @@
-import type { NodePath } from '@babel/traverse'
-import type { CallExpression, ImportDeclaration } from '@babel/types'
 import { isNode } from '@babel/types'
-import type {
+import {
   FileExtension,
+  trext,
   TrextMatch,
+  TrextNodePath,
   TrextOptions
 } from '@flex-development/trext'
-import { trext } from '@flex-development/trext'
+import Trextel from '@flex-development/trext/plugins/trextel.plugin'
 import { inspect } from 'util'
 
 /**
@@ -20,16 +20,30 @@ const TREXT_OPTIONS: TrextOptions<'js', 'cjs' | 'mjs'> = {
   to(match: TrextMatch, ...args: any[]): FileExtension<'cjs' | 'mjs'> {
     // Check if match is NodePath, args === []
     if (isNode((match as any).node)) {
-      const nodePath = match as NodePath<CallExpression | ImportDeclaration>
-
-      if (nodePath.type === 'CallExpression') {
-        //
+      const nodePath = match as TrextNodePath
+      const code: string | undefined = Trextel.getCode(nodePath)
+
+      switch (nodePath.type) {
+        case 'CallExpression':
+          //
+          break
+        case 'ExportAllDeclaration':
+          //
+          break
+        case 'ExportNamedDeclaration':
+          //
+          break
+        case 'ImportDeclaration':
+          //
+          break
+        default:
+          break
       }
 
       return '.mjs'
     }
 
-    // Check is match is RegExp object
+    // Check if match is RegExp object
     if (match.constructor.name === 'RegExp') {
       const regex = match as RegExp
 

docs/examples/mandatory-by-node.example.ts

@@ -0,0 +1,24 @@
+import type { TrextOptions } from '@flex-development/trext'
+import { trext } from '@flex-development/trext'
+import { inspect } from 'util'
+
+/**
+ * @file Examples - Disabling Mandatory File Extensions (By Node)
+ * @module docs/examples/mandatory-by-node
+ */
+
+const TREXT_OPTIONS: TrextOptions<'js', 'mjs'> = {
+  from: 'js',
+  mandatory: {
+    call: false,
+    exportAll: true,
+    exportNamed: false,
+    import: true
+  },
+  pattern: /.js$/,
+  to: 'mjs'
+}
+
+trext('mjs/', TREXT_OPTIONS)
+  .then(results => console.info(inspect(results, false, null)))
+  .catch(error => console.error(inspect(error, false, null)))

docs/examples/mandatory.example.ts

@@ -0,0 +1,19 @@
+import type { TrextOptions } from '@flex-development/trext'
+import { trext } from '@flex-development/trext'
+import { inspect } from 'util'
+
+/**
+ * @file Examples - Disabling Mandatory File Extensions
+ * @module docs/examples/mandatory
+ */
+
+const TREXT_OPTIONS: TrextOptions<'js', 'mjs'> = {
+  from: 'js',
+  mandatory: false,
+  pattern: /.js$/,
+  to: 'mjs'
+}
+
+trext('esm/', TREXT_OPTIONS)
+  .then(results => console.info(inspect(results, false, null)))
+  .catch(error => console.error(inspect(error, false, null)))

src/config/defaults.config.ts

@@ -7,6 +7,7 @@ import type { TrextDefaults } from '@trext/types'
 
 const DEFAULTS: TrextDefaults = {
   babel: {},
+  mandatory: true,
   pattern: /\..+$/,
   src: `${process.cwd()}/src`
 }

src/index.ts

@@ -5,5 +5,7 @@
 
 export { default as TREXT_DEFAULTS } from './config/defaults.config'
 export * from './interfaces'
-export { default as Trext, trext, trextFile } from './plugins/trext.plugin'
+export * from './plugins'
+export { trext, trextFile } from './plugins/trext.plugin'
 export * from './types'
+export * from './utils'

src/interfaces/trext-options.interface.ts

@@ -25,6 +25,18 @@ interface TrextOptions<F extends string = string, T extends string = string> {
    */
   from: F
 
+  /**
+   * Add file extensions to all call expression arguments and module specifiers.
+   *
+   * @see https://nodejs.org/api/esm.html#esm_import_specifiers
+   * @see https://nodejs.org/api/esm.html#esm_mandatory_file_extensions
+   *
+   * @default true
+   */
+  mandatory?:
+    | boolean
+    | Partial<Record<'call' | 'exportAll' | 'exportNamed' | 'import', boolean>>
+
   /**
    * File extension search pattern.
    *