@rollup/plugin-commonjs/types/index.d.ts

Convert CommonJS modules to ES2015

import type { FilterPattern } from '@rollup/pluginutils';
import type { Plugin } from 'rollup';

type RequireReturnsDefaultOption = boolean | 'auto' | 'preferred' | 'namespace';
type DefaultIsModuleExportsOption = boolean | 'auto';

interface RollupCommonJSOptions {
  /**
   * A picomatch pattern, or array of patterns, which specifies the files in
   * the build the plugin should operate on. By default, all files with
   * extension `".cjs"` or those in `extensions` are included, but you can
   * narrow this list by only including specific files. These files will be
   * analyzed and transpiled if either the analysis does not find ES module
   * specific statements or `transformMixedEsModules` is `true`.
   * @default undefined
   */
  include?: FilterPattern;
  /**
   * A picomatch pattern, or array of patterns, which specifies the files in
   * the build the plugin should _ignore_. By default, all files with
   * extensions other than those in `extensions` or `".cjs"` are ignored, but you
   * can exclude additional files. See also the `include` option.
   * @default undefined
   */
  exclude?: FilterPattern;
  /**
   * For extensionless imports, search for extensions other than .js in the
   * order specified. Note that you need to make sure that non-JavaScript files
   * are transpiled by another plugin first.
   * @default [ '.js' ]
   */
  extensions?: ReadonlyArray<string>;
  /**
   * If true then uses of `global` won't be dealt with by this plugin
   * @default false
   */
  ignoreGlobal?: boolean;
  /**
   * If false, skips source map generation for CommonJS modules. This will
   * improve performance.
   * @default true
   */
  sourceMap?: boolean;
  /**
   * Some `require` calls cannot be resolved statically to be translated to
   * imports.
   * When this option is set to `false`, the generated code will either
   * directly throw an error when such a call is encountered or, when
   * `dynamicRequireTargets` is used, when such a call cannot be resolved with a
   * configured dynamic require target.
   * Setting this option to `true` will instead leave the `require` call in the
   * code or use it as a fallback for `dynamicRequireTargets`.
   * @default false
   */
  ignoreDynamicRequires?: boolean;
  /**
   * Instructs the plugin whether to enable mixed module transformations. This
   * is useful in scenarios with modules that contain a mix of ES `import`
   * statements and CommonJS `require` expressions. Set to `true` if `require`
   * calls should be transformed to imports in mixed modules, or `false` if the
   * `require` expressions should survive the transformation. The latter can be
   * important if the code contains environment detection, or you are coding
   * for an environment with special treatment for `require` calls such as
   * ElectronJS. See also the `ignore` option.
   * @default false
   */
  transformMixedEsModules?: boolean;
  /**
   * By default, this plugin will try to hoist `require` statements as imports
   * to the top of each file. While this works well for many code bases and
   * allows for very efficient ESM output, it does not perfectly capture
   * CommonJS semantics as the order of side effects like log statements may
   * change. But it is especially problematic when there are circular `require`
   * calls between CommonJS modules as those often rely on the lazy execution of
   * nested `require` calls.
   *
   * Setting this option to `true` will wrap all CommonJS files in functions
   * which are executed when they are required for the first time, preserving
   * NodeJS semantics. Note that this can have an impact on the size and
   * performance of the generated code.
   *
   * The default value of `"auto"` will only wrap CommonJS files when they are
   * part of a CommonJS dependency cycle, e.g. an index file that is required by
   * many of its dependencies. All other CommonJS files are hoisted. This is the
   * recommended setting for most code bases.
   *
   * `false` will entirely prevent wrapping and hoist all files. This may still
   * work depending on the nature of cyclic dependencies but will often cause
   * problems.
   *
   * You can also provide a picomatch pattern, or array of patterns, to only
   * specify a subset of files which should be wrapped in functions for proper
   * `require` semantics.
   *
   * `"debug"` works like `"auto"` but after bundling, it will display a warning
   * containing a list of ids that have been wrapped which can be used as
   * picomatch pattern for fine-tuning.
   * @default "auto"
   */
  strictRequires?: boolean | FilterPattern;
  /**
   * Sometimes you have to leave require statements unconverted. Pass an array
   * containing the IDs or a `id => boolean` function.
   * @default []
   */
  ignore?: ReadonlyArray<string> | ((id: string) => boolean);
  /**
   * In most cases, where `require` calls are inside a `try-catch` clause,
   * they should be left unconverted as it requires an optional dependency
   * that may or may not be installed beside the rolled up package.
   * Due to the conversion of `require` to a static `import` - the call is
   * hoisted to the top of the file, outside the `try-catch` clause.
   *
   * - `true`: Default. All `require` calls inside a `try` will be left unconverted.
   * - `false`: All `require` calls inside a `try` will be converted as if the
   *   `try-catch` clause is not there.
   * - `remove`: Remove all `require` calls from inside any `try` block.
   * - `string[]`: Pass an array containing the IDs to left unconverted.
   * - `((id: string) => boolean|'remove')`: Pass a function that controls
   *   individual IDs.
   *
   * @default true
   */
  ignoreTryCatch?:
    | boolean
    | 'remove'
    | ReadonlyArray<string>
    | ((id: string) => boolean | 'remove');
  /**
   * Controls how to render imports from external dependencies. By default,
   * this plugin assumes that all external dependencies are CommonJS. This
   * means they are rendered as default imports to be compatible with e.g.
   * NodeJS where ES modules can only import a default export from a CommonJS
   * dependency.
   *
   * If you set `esmExternals` to `true`, this plugin assumes that all
   * external dependencies are ES modules and respect the
   * `requireReturnsDefault` option. If that option is not set, they will be
   * rendered as namespace imports.
   *
   * You can also supply an array of ids to be treated as ES modules, or a
   * function that will be passed each external id to determine whether it is
   * an ES module.
   * @default false
   */
  esmExternals?: boolean | ReadonlyArray<string> | ((id: string) => boolean);
  /**
   * Controls what is returned when requiring an ES module from a CommonJS file.
   * When using the `esmExternals` option, this will also apply to external
   * modules. By default, this plugin will render those imports as namespace
   * imports i.e.
   *
   * ```js
   * // input
   * const foo = require('foo');
   *
   * // output
   * import * as foo from 'foo';
   * ```
   *
   * However, there are some situations where this may not be desired.
   * For these situations, you can change Rollup's behaviour either globally or
   * per module. To change it globally, set the `requireReturnsDefault` option
   * to one of the following values:
   *
   * - `false`: This is the default, requiring an ES module returns its
   *   namespace. This is the only option that will also add a marker
   *   `__esModule: true` to the namespace to support interop patterns in
   *   CommonJS modules that are transpiled ES modules.
   * - `"namespace"`: Like `false`, requiring an ES module returns its
   *   namespace, but the plugin does not add the `__esModule` marker and thus
   *   creates more efficient code. For external dependencies when using
   *   `esmExternals: true`, no additional interop code is generated.
   * - `"auto"`: This is complementary to how `output.exports: "auto"` works in
   *   Rollup: If a module has a default export and no named exports, requiring
   *   that module returns the default export. In all other cases, the namespace
   *   is returned. For external dependencies when using `esmExternals: true`, a
   *   corresponding interop helper is added.
   * - `"preferred"`: If a module has a default export, requiring that module
   *   always returns the default export, no matter whether additional named
   *   exports exist. This is similar to how previous versions of this plugin
   *   worked. Again for external dependencies when using `esmExternals: true`,
   *   an interop helper is added.
   * - `true`: This will always try to return the default export on require
   *   without checking if it actually exists. This can throw at build time if
   *   there is no default export. This is how external dependencies are handled
   *   when `esmExternals` is not used. The advantage over the other options is
   *   that, like `false`, this does not add an interop helper for external
   *   dependencies, keeping the code lean.
   *
   * To change this for individual modules, you can supply a function for
   * `requireReturnsDefault` instead. This function will then be called once for
   * each required ES module or external dependency with the corresponding id
   * and allows you to return different values for different modules.
   * @default false
   */
  requireReturnsDefault?:
    | RequireReturnsDefaultOption
    | ((id: string) => RequireReturnsDefaultOption);

  /**
   * @default "auto"
   */
  defaultIsModuleExports?:
    | DefaultIsModuleExportsOption
    | ((id: string) => DefaultIsModuleExportsOption);
  /**
   * Some modules contain dynamic `require` calls, or require modules that
   * contain circular dependencies, which are not handled well by static
   * imports. Including those modules as `dynamicRequireTargets` will simulate a
   * CommonJS (NodeJS-like) environment for them with support for dynamic
   * dependencies. It also enables `strictRequires` for those modules.
   *
   * Note: In extreme cases, this feature may result in some paths being
   * rendered as absolute in the final bundle. The plugin tries to avoid
   * exposing paths from the local machine, but if you are `dynamicRequirePaths`
   * with paths that are far away from your project's folder, that may require
   * replacing strings like `"/Users/John/Desktop/foo-project/"` -> `"/"`.
   */
  dynamicRequireTargets?: string | ReadonlyArray<string>;
  /**
   * To avoid long paths when using the `dynamicRequireTargets` option, you can use this option to specify a directory
   * that is a common parent for all files that use dynamic require statements. Using a directory higher up such as `/`
   * may lead to unnecessarily long paths in the generated code and may expose directory names on your machine like your
   * home directory name. By default, it uses the current working directory.
   */
  dynamicRequireRoot?: string;
}

/**
 * Convert CommonJS modules to ES6, so they can be included in a Rollup bundle
 */
export default function commonjs(options?: RollupCommonJSOptions): Plugin;