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922 lines (922 loc) 路 39.3 KB
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/**
* The `node:vm` module enables compiling and running code within V8 Virtual
* Machine contexts.
*
* **The `node:vm` module is not a security**
* **mechanism. Do not use it to run untrusted code.**
*
* JavaScript code can be compiled and run immediately or
* compiled, saved, and run later.
*
* A common use case is to run the code in a different V8 Context. This means
* invoked code has a different global object than the invoking code.
*
* One can provide the context by `contextifying` an
* object. The invoked code treats any property in the context like a
* global variable. Any changes to global variables caused by the invoked
* code are reflected in the context object.
*
* ```js
* const vm = require('node:vm');
*
* const x = 1;
*
* const context = { x: 2 };
* vm.createContext(context); // Contextify the object.
*
* const code = 'x += 40; var y = 17;';
* // `x` and `y` are global variables in the context.
* // Initially, x has the value 2 because that is the value of context.x.
* vm.runInContext(code, context);
*
* console.log(context.x); // 42
* console.log(context.y); // 17
*
* console.log(x); // 1; y is not defined.
* ```
* @see [source](https://github.com/nodejs/node/blob/v22.x/lib/vm.js)
*/
declare module "vm" {
import { ImportAttributes } from "node:module";
interface Context extends NodeJS.Dict<any> {}
interface BaseOptions {
/**
* Specifies the filename used in stack traces produced by this script.
* @default ''
*/
filename?: string | undefined;
/**
* Specifies the line number offset that is displayed in stack traces produced by this script.
* @default 0
*/
lineOffset?: number | undefined;
/**
* Specifies the column number offset that is displayed in stack traces produced by this script.
* @default 0
*/
columnOffset?: number | undefined;
}
interface ScriptOptions extends BaseOptions {
/**
* V8's code cache data for the supplied source.
*/
cachedData?: Buffer | NodeJS.ArrayBufferView | undefined;
/** @deprecated in favor of `script.createCachedData()` */
produceCachedData?: boolean | undefined;
/**
* Used to specify how the modules should be loaded during the evaluation of this script when `import()` is called. This option is
* part of the experimental modules API. We do not recommend using it in a production environment. For detailed information, see
* [Support of dynamic `import()` in compilation APIs](https://nodejs.org/docs/latest-v22.x/api/vm.html#support-of-dynamic-import-in-compilation-apis).
*/
importModuleDynamically?:
| ((specifier: string, script: Script, importAttributes: ImportAttributes) => Module)
| typeof constants.USE_MAIN_CONTEXT_DEFAULT_LOADER
| undefined;
}
interface RunningScriptOptions extends BaseOptions {
/**
* When `true`, if an `Error` occurs while compiling the `code`, the line of code causing the error is attached to the stack trace.
* @default true
*/
displayErrors?: boolean | undefined;
/**
* Specifies the number of milliseconds to execute code before terminating execution.
* If execution is terminated, an `Error` will be thrown. This value must be a strictly positive integer.
*/
timeout?: number | undefined;
/**
* If `true`, the execution will be terminated when `SIGINT` (Ctrl+C) is received.
* Existing handlers for the event that have been attached via `process.on('SIGINT')` will be disabled during script execution, but will continue to work after that.
* If execution is terminated, an `Error` will be thrown.
* @default false
*/
breakOnSigint?: boolean | undefined;
}
interface RunningScriptInNewContextOptions extends RunningScriptOptions {
/**
* Human-readable name of the newly created context.
*/
contextName?: CreateContextOptions["name"];
/**
* Origin corresponding to the newly created context for display purposes. The origin should be formatted like a URL,
* but with only the scheme, host, and port (if necessary), like the value of the `url.origin` property of a `URL` object.
* Most notably, this string should omit the trailing slash, as that denotes a path.
*/
contextOrigin?: CreateContextOptions["origin"];
contextCodeGeneration?: CreateContextOptions["codeGeneration"];
/**
* If set to `afterEvaluate`, microtasks will be run immediately after the script has run.
*/
microtaskMode?: CreateContextOptions["microtaskMode"];
}
interface RunningCodeOptions extends RunningScriptOptions {
cachedData?: ScriptOptions["cachedData"];
importModuleDynamically?: ScriptOptions["importModuleDynamically"];
}
interface RunningCodeInNewContextOptions extends RunningScriptInNewContextOptions {
cachedData?: ScriptOptions["cachedData"];
importModuleDynamically?: ScriptOptions["importModuleDynamically"];
}
interface CompileFunctionOptions extends BaseOptions {
/**
* Provides an optional data with V8's code cache data for the supplied source.
*/
cachedData?: Buffer | undefined;
/**
* Specifies whether to produce new cache data.
* @default false
*/
produceCachedData?: boolean | undefined;
/**
* The sandbox/context in which the said function should be compiled in.
*/
parsingContext?: Context | undefined;
/**
* An array containing a collection of context extensions (objects wrapping the current scope) to be applied while compiling
*/
contextExtensions?: Object[] | undefined;
}
interface CreateContextOptions {
/**
* Human-readable name of the newly created context.
* @default 'VM Context i' Where i is an ascending numerical index of the created context.
*/
name?: string | undefined;
/**
* Corresponds to the newly created context for display purposes.
* The origin should be formatted like a `URL`, but with only the scheme, host, and port (if necessary),
* like the value of the `url.origin` property of a URL object.
* Most notably, this string should omit the trailing slash, as that denotes a path.
* @default ''
*/
origin?: string | undefined;
codeGeneration?:
| {
/**
* If set to false any calls to eval or function constructors (Function, GeneratorFunction, etc)
* will throw an EvalError.
* @default true
*/
strings?: boolean | undefined;
/**
* If set to false any attempt to compile a WebAssembly module will throw a WebAssembly.CompileError.
* @default true
*/
wasm?: boolean | undefined;
}
| undefined;
/**
* If set to `afterEvaluate`, microtasks will be run immediately after the script has run.
*/
microtaskMode?: "afterEvaluate" | undefined;
}
type MeasureMemoryMode = "summary" | "detailed";
interface MeasureMemoryOptions {
/**
* @default 'summary'
*/
mode?: MeasureMemoryMode | undefined;
/**
* @default 'default'
*/
execution?: "default" | "eager" | undefined;
}
interface MemoryMeasurement {
total: {
jsMemoryEstimate: number;
jsMemoryRange: [number, number];
};
}
/**
* Instances of the `vm.Script` class contain precompiled scripts that can be
* executed in specific contexts.
* @since v0.3.1
*/
class Script {
constructor(code: string, options?: ScriptOptions | string);
/**
* Runs the compiled code contained by the `vm.Script` object within the given `contextifiedObject` and returns the result. Running code does not have access
* to local scope.
*
* The following example compiles code that increments a global variable, sets
* the value of another global variable, then execute the code multiple times.
* The globals are contained in the `context` object.
*
* ```js
* const vm = require('node:vm');
*
* const context = {
* animal: 'cat',
* count: 2,
* };
*
* const script = new vm.Script('count += 1; name = "kitty";');
*
* vm.createContext(context);
* for (let i = 0; i < 10; ++i) {
* script.runInContext(context);
* }
*
* console.log(context);
* // Prints: { animal: 'cat', count: 12, name: 'kitty' }
* ```
*
* Using the `timeout` or `breakOnSigint` options will result in new event loops
* and corresponding threads being started, which have a non-zero performance
* overhead.
* @since v0.3.1
* @param contextifiedObject A `contextified` object as returned by the `vm.createContext()` method.
* @return the result of the very last statement executed in the script.
*/
runInContext(contextifiedObject: Context, options?: RunningScriptOptions): any;
/**
* First contextifies the given `contextObject`, runs the compiled code contained
* by the `vm.Script` object within the created context, and returns the result.
* Running code does not have access to local scope.
*
* The following example compiles code that sets a global variable, then executes
* the code multiple times in different contexts. The globals are set on and
* contained within each individual `context`.
*
* ```js
* const vm = require('node:vm');
*
* const script = new vm.Script('globalVar = "set"');
*
* const contexts = [{}, {}, {}];
* contexts.forEach((context) => {
* script.runInNewContext(context);
* });
*
* console.log(contexts);
* // Prints: [{ globalVar: 'set' }, { globalVar: 'set' }, { globalVar: 'set' }]
* ```
* @since v0.3.1
* @param contextObject An object that will be `contextified`. If `undefined`, a new object will be created.
* @return the result of the very last statement executed in the script.
*/
runInNewContext(contextObject?: Context, options?: RunningScriptInNewContextOptions): any;
/**
* Runs the compiled code contained by the `vm.Script` within the context of the
* current `global` object. Running code does not have access to local scope, but _does_ have access to the current `global` object.
*
* The following example compiles code that increments a `global` variable then
* executes that code multiple times:
*
* ```js
* const vm = require('node:vm');
*
* global.globalVar = 0;
*
* const script = new vm.Script('globalVar += 1', { filename: 'myfile.vm' });
*
* for (let i = 0; i < 1000; ++i) {
* script.runInThisContext();
* }
*
* console.log(globalVar);
*
* // 1000
* ```
* @since v0.3.1
* @return the result of the very last statement executed in the script.
*/
runInThisContext(options?: RunningScriptOptions): any;
/**
* Creates a code cache that can be used with the `Script` constructor's `cachedData` option. Returns a `Buffer`. This method may be called at any
* time and any number of times.
*
* The code cache of the `Script` doesn't contain any JavaScript observable
* states. The code cache is safe to be saved along side the script source and
* used to construct new `Script` instances multiple times.
*
* Functions in the `Script` source can be marked as lazily compiled and they are
* not compiled at construction of the `Script`. These functions are going to be
* compiled when they are invoked the first time. The code cache serializes the
* metadata that V8 currently knows about the `Script` that it can use to speed up
* future compilations.
*
* ```js
* const script = new vm.Script(`
* function add(a, b) {
* return a + b;
* }
*
* const x = add(1, 2);
* `);
*
* const cacheWithoutAdd = script.createCachedData();
* // In `cacheWithoutAdd` the function `add()` is marked for full compilation
* // upon invocation.
*
* script.runInThisContext();
*
* const cacheWithAdd = script.createCachedData();
* // `cacheWithAdd` contains fully compiled function `add()`.
* ```
* @since v10.6.0
*/
createCachedData(): Buffer;
/** @deprecated in favor of `script.createCachedData()` */
cachedDataProduced?: boolean | undefined;
/**
* When `cachedData` is supplied to create the `vm.Script`, this value will be set
* to either `true` or `false` depending on acceptance of the data by V8.
* Otherwise the value is `undefined`.
* @since v5.7.0
*/
cachedDataRejected?: boolean | undefined;
cachedData?: Buffer | undefined;
/**
* When the script is compiled from a source that contains a source map magic
* comment, this property will be set to the URL of the source map.
*
* ```js
* import vm from 'node:vm';
*
* const script = new vm.Script(`
* function myFunc() {}
* //# sourceMappingURL=sourcemap.json
* `);
*
* console.log(script.sourceMapURL);
* // Prints: sourcemap.json
* ```
* @since v19.1.0, v18.13.0
*/
sourceMapURL?: string | undefined;
}
/**
* If given a `contextObject`, the `vm.createContext()` method will
* [prepare that object](https://nodejs.org/docs/latest-v22.x/api/vm.html#what-does-it-mean-to-contextify-an-object)
* and return a reference to it so that it can be used in `{@link runInContext}` or
* [`script.runInContext()`](https://nodejs.org/docs/latest-v22.x/api/vm.html#scriptrunincontextcontextifiedobject-options). Inside such
* scripts, the `contextObject` will be the global object, retaining all of its
* existing properties but also having the built-in objects and functions any
* standard [global object](https://es5.github.io/#x15.1) has. Outside of scripts run by the vm module, global
* variables will remain unchanged.
*
* ```js
* const vm = require('node:vm');
*
* global.globalVar = 3;
*
* const context = { globalVar: 1 };
* vm.createContext(context);
*
* vm.runInContext('globalVar *= 2;', context);
*
* console.log(context);
* // Prints: { globalVar: 2 }
*
* console.log(global.globalVar);
* // Prints: 3
* ```
*
* If `contextObject` is omitted (or passed explicitly as `undefined`), a new,
* empty `contextified` object will be returned.
*
* The `vm.createContext()` method is primarily useful for creating a single
* context that can be used to run multiple scripts. For instance, if emulating a
* web browser, the method can be used to create a single context representing a
* window's global object, then run all `<script>` tags together within that
* context.
*
* The provided `name` and `origin` of the context are made visible through the
* Inspector API.
* @since v0.3.1
* @return contextified object.
*/
function createContext(sandbox?: Context, options?: CreateContextOptions): Context;
/**
* Returns `true` if the given `object` object has been `contextified` using {@link createContext}.
* @since v0.11.7
*/
function isContext(sandbox: Context): boolean;
/**
* The `vm.runInContext()` method compiles `code`, runs it within the context of
* the `contextifiedObject`, then returns the result. Running code does not have
* access to the local scope. The `contextifiedObject` object _must_ have been
* previously `contextified` using the {@link createContext} method.
*
* If `options` is a string, then it specifies the filename.
*
* The following example compiles and executes different scripts using a single `contextified` object:
*
* ```js
* const vm = require('node:vm');
*
* const contextObject = { globalVar: 1 };
* vm.createContext(contextObject);
*
* for (let i = 0; i < 10; ++i) {
* vm.runInContext('globalVar *= 2;', contextObject);
* }
* console.log(contextObject);
* // Prints: { globalVar: 1024 }
* ```
* @since v0.3.1
* @param code The JavaScript code to compile and run.
* @param contextifiedObject The `contextified` object that will be used as the `global` when the `code` is compiled and run.
* @return the result of the very last statement executed in the script.
*/
function runInContext(code: string, contextifiedObject: Context, options?: RunningCodeOptions | string): any;
/**
* The `vm.runInNewContext()` first contextifies the given `contextObject` (or
* creates a new `contextObject` if passed as `undefined`), compiles the `code`,
* runs it within the created context, then returns the result. Running code
* does not have access to the local scope.
*
* If `options` is a string, then it specifies the filename.
*
* The following example compiles and executes code that increments a global
* variable and sets a new one. These globals are contained in the `contextObject`.
*
* ```js
* const vm = require('node:vm');
*
* const contextObject = {
* animal: 'cat',
* count: 2,
* };
*
* vm.runInNewContext('count += 1; name = "kitty"', contextObject);
* console.log(contextObject);
* // Prints: { animal: 'cat', count: 3, name: 'kitty' }
* ```
* @since v0.3.1
* @param code The JavaScript code to compile and run.
* @param contextObject An object that will be `contextified`. If `undefined`, a new object will be created.
* @return the result of the very last statement executed in the script.
*/
function runInNewContext(
code: string,
contextObject?: Context,
options?: RunningCodeInNewContextOptions | string,
): any;
/**
* `vm.runInThisContext()` compiles `code`, runs it within the context of the
* current `global` and returns the result. Running code does not have access to
* local scope, but does have access to the current `global` object.
*
* If `options` is a string, then it specifies the filename.
*
* The following example illustrates using both `vm.runInThisContext()` and
* the JavaScript [`eval()`](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/eval) function to run the same code:
*
* ```js
* const vm = require('node:vm');
* let localVar = 'initial value';
*
* const vmResult = vm.runInThisContext('localVar = "vm";');
* console.log(`vmResult: '${vmResult}', localVar: '${localVar}'`);
* // Prints: vmResult: 'vm', localVar: 'initial value'
*
* const evalResult = eval('localVar = "eval";');
* console.log(`evalResult: '${evalResult}', localVar: '${localVar}'`);
* // Prints: evalResult: 'eval', localVar: 'eval'
* ```
*
* Because `vm.runInThisContext()` does not have access to the local scope, `localVar` is unchanged. In contrast,
* [`eval()`](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/eval) _does_ have access to the
* local scope, so the value `localVar` is changed. In this way `vm.runInThisContext()` is much like an [indirect `eval()` call](https://es5.github.io/#x10.4.2), e.g.`(0,eval)('code')`.
*
* ## Example: Running an HTTP server within a VM
*
* When using either `script.runInThisContext()` or {@link runInThisContext}, the code is executed within the current V8 global
* context. The code passed to this VM context will have its own isolated scope.
*
* In order to run a simple web server using the `node:http` module the code passed
* to the context must either call `require('node:http')` on its own, or have a
* reference to the `node:http` module passed to it. For instance:
*
* ```js
* 'use strict';
* const vm = require('node:vm');
*
* const code = `
* ((require) => {
* const http = require('node:http');
*
* http.createServer((request, response) => {
* response.writeHead(200, { 'Content-Type': 'text/plain' });
* response.end('Hello World\\n');
* }).listen(8124);
*
* console.log('Server running at http://127.0.0.1:8124/');
* })`;
*
* vm.runInThisContext(code)(require);
* ```
*
* The `require()` in the above case shares the state with the context it is
* passed from. This may introduce risks when untrusted code is executed, e.g.
* altering objects in the context in unwanted ways.
* @since v0.3.1
* @param code The JavaScript code to compile and run.
* @return the result of the very last statement executed in the script.
*/
function runInThisContext(code: string, options?: RunningCodeOptions | string): any;
/**
* Compiles the given code into the provided context (if no context is
* supplied, the current context is used), and returns it wrapped inside a
* function with the given `params`.
* @since v10.10.0
* @param code The body of the function to compile.
* @param params An array of strings containing all parameters for the function.
*/
function compileFunction(
code: string,
params?: readonly string[],
options?: CompileFunctionOptions,
): Function & {
cachedData?: Script["cachedData"] | undefined;
cachedDataProduced?: Script["cachedDataProduced"] | undefined;
cachedDataRejected?: Script["cachedDataRejected"] | undefined;
};
/**
* Measure the memory known to V8 and used by all contexts known to the
* current V8 isolate, or the main context.
*
* The format of the object that the returned Promise may resolve with is
* specific to the V8 engine and may change from one version of V8 to the next.
*
* The returned result is different from the statistics returned by `v8.getHeapSpaceStatistics()` in that `vm.measureMemory()` measure the
* memory reachable by each V8 specific contexts in the current instance of
* the V8 engine, while the result of `v8.getHeapSpaceStatistics()` measure
* the memory occupied by each heap space in the current V8 instance.
*
* ```js
* const vm = require('node:vm');
* // Measure the memory used by the main context.
* vm.measureMemory({ mode: 'summary' })
* // This is the same as vm.measureMemory()
* .then((result) => {
* // The current format is:
* // {
* // total: {
* // jsMemoryEstimate: 2418479, jsMemoryRange: [ 2418479, 2745799 ]
* // }
* // }
* console.log(result);
* });
*
* const context = vm.createContext({ a: 1 });
* vm.measureMemory({ mode: 'detailed', execution: 'eager' })
* .then((result) => {
* // Reference the context here so that it won't be GC'ed
* // until the measurement is complete.
* console.log(context.a);
* // {
* // total: {
* // jsMemoryEstimate: 2574732,
* // jsMemoryRange: [ 2574732, 2904372 ]
* // },
* // current: {
* // jsMemoryEstimate: 2438996,
* // jsMemoryRange: [ 2438996, 2768636 ]
* // },
* // other: [
* // {
* // jsMemoryEstimate: 135736,
* // jsMemoryRange: [ 135736, 465376 ]
* // }
* // ]
* // }
* console.log(result);
* });
* ```
* @since v13.10.0
* @experimental
*/
function measureMemory(options?: MeasureMemoryOptions): Promise<MemoryMeasurement>;
interface ModuleEvaluateOptions {
timeout?: RunningScriptOptions["timeout"] | undefined;
breakOnSigint?: RunningScriptOptions["breakOnSigint"] | undefined;
}
type ModuleLinker = (
specifier: string,
referencingModule: Module,
extra: {
attributes: ImportAttributes;
},
) => Module | Promise<Module>;
type ModuleStatus = "unlinked" | "linking" | "linked" | "evaluating" | "evaluated" | "errored";
/**
* This feature is only available with the `--experimental-vm-modules` command
* flag enabled.
*
* The `vm.Module` class provides a low-level interface for using
* ECMAScript modules in VM contexts. It is the counterpart of the `vm.Script` class that closely mirrors [Module Record](https://262.ecma-international.org/14.0/#sec-abstract-module-records) s as
* defined in the ECMAScript
* specification.
*
* Unlike `vm.Script` however, every `vm.Module` object is bound to a context from
* its creation. Operations on `vm.Module` objects are intrinsically asynchronous,
* in contrast with the synchronous nature of `vm.Script` objects. The use of
* 'async' functions can help with manipulating `vm.Module` objects.
*
* Using a `vm.Module` object requires three distinct steps: creation/parsing,
* linking, and evaluation. These three steps are illustrated in the following
* example.
*
* This implementation lies at a lower level than the `ECMAScript Module
* loader`. There is also no way to interact with the Loader yet, though
* support is planned.
*
* ```js
* import vm from 'node:vm';
*
* const contextifiedObject = vm.createContext({
* secret: 42,
* print: console.log,
* });
*
* // Step 1
* //
* // Create a Module by constructing a new `vm.SourceTextModule` object. This
* // parses the provided source text, throwing a `SyntaxError` if anything goes
* // wrong. By default, a Module is created in the top context. But here, we
* // specify `contextifiedObject` as the context this Module belongs to.
* //
* // Here, we attempt to obtain the default export from the module "foo", and
* // put it into local binding "secret".
*
* const bar = new vm.SourceTextModule(`
* import s from 'foo';
* s;
* print(s);
* `, { context: contextifiedObject });
*
* // Step 2
* //
* // "Link" the imported dependencies of this Module to it.
* //
* // The provided linking callback (the "linker") accepts two arguments: the
* // parent module (`bar` in this case) and the string that is the specifier of
* // the imported module. The callback is expected to return a Module that
* // corresponds to the provided specifier, with certain requirements documented
* // in `module.link()`.
* //
* // If linking has not started for the returned Module, the same linker
* // callback will be called on the returned Module.
* //
* // Even top-level Modules without dependencies must be explicitly linked. The
* // callback provided would never be called, however.
* //
* // The link() method returns a Promise that will be resolved when all the
* // Promises returned by the linker resolve.
* //
* // Note: This is a contrived example in that the linker function creates a new
* // "foo" module every time it is called. In a full-fledged module system, a
* // cache would probably be used to avoid duplicated modules.
*
* async function linker(specifier, referencingModule) {
* if (specifier === 'foo') {
* return new vm.SourceTextModule(`
* // The "secret" variable refers to the global variable we added to
* // "contextifiedObject" when creating the context.
* export default secret;
* `, { context: referencingModule.context });
*
* // Using `contextifiedObject` instead of `referencingModule.context`
* // here would work as well.
* }
* throw new Error(`Unable to resolve dependency: ${specifier}`);
* }
* await bar.link(linker);
*
* // Step 3
* //
* // Evaluate the Module. The evaluate() method returns a promise which will
* // resolve after the module has finished evaluating.
*
* // Prints 42.
* await bar.evaluate();
* ```
* @since v13.0.0, v12.16.0
* @experimental
*/
class Module {
/**
* The specifiers of all dependencies of this module. The returned array is frozen
* to disallow any changes to it.
*
* Corresponds to the `[[RequestedModules]]` field of [Cyclic Module Record](https://tc39.es/ecma262/#sec-cyclic-module-records) s in
* the ECMAScript specification.
*/
dependencySpecifiers: readonly string[];
/**
* If the `module.status` is `'errored'`, this property contains the exception
* thrown by the module during evaluation. If the status is anything else,
* accessing this property will result in a thrown exception.
*
* The value `undefined` cannot be used for cases where there is not a thrown
* exception due to possible ambiguity with `throw undefined;`.
*
* Corresponds to the `[[EvaluationError]]` field of [Cyclic Module Record](https://tc39.es/ecma262/#sec-cyclic-module-records) s
* in the ECMAScript specification.
*/
error: any;
/**
* The identifier of the current module, as set in the constructor.
*/
identifier: string;
context: Context;
/**
* The namespace object of the module. This is only available after linking
* (`module.link()`) has completed.
*
* Corresponds to the [GetModuleNamespace](https://tc39.es/ecma262/#sec-getmodulenamespace) abstract operation in the ECMAScript
* specification.
*/
namespace: Object;
/**
* The current status of the module. Will be one of:
*
* * `'unlinked'`: `module.link()` has not yet been called.
* * `'linking'`: `module.link()` has been called, but not all Promises returned
* by the linker function have been resolved yet.
* * `'linked'`: The module has been linked successfully, and all of its
* dependencies are linked, but `module.evaluate()` has not yet been called.
* * `'evaluating'`: The module is being evaluated through a `module.evaluate()` on
* itself or a parent module.
* * `'evaluated'`: The module has been successfully evaluated.
* * `'errored'`: The module has been evaluated, but an exception was thrown.
*
* Other than `'errored'`, this status string corresponds to the specification's [Cyclic Module Record](https://tc39.es/ecma262/#sec-cyclic-module-records)'s `[[Status]]` field. `'errored'`
* corresponds to `'evaluated'` in the specification, but with `[[EvaluationError]]` set to a
* value that is not `undefined`.
*/
status: ModuleStatus;
/**
* Evaluate the module.
*
* This must be called after the module has been linked; otherwise it will reject.
* It could be called also when the module has already been evaluated, in which
* case it will either do nothing if the initial evaluation ended in success
* (`module.status` is `'evaluated'`) or it will re-throw the exception that the
* initial evaluation resulted in (`module.status` is `'errored'`).
*
* This method cannot be called while the module is being evaluated
* (`module.status` is `'evaluating'`).
*
* Corresponds to the [Evaluate() concrete method](https://tc39.es/ecma262/#sec-moduleevaluation) field of [Cyclic Module Record](https://tc39.es/ecma262/#sec-cyclic-module-records) s in the
* ECMAScript specification.
* @return Fulfills with `undefined` upon success.
*/
evaluate(options?: ModuleEvaluateOptions): Promise<void>;
/**
* Link module dependencies. This method must be called before evaluation, and
* can only be called once per module.
*
* The function is expected to return a `Module` object or a `Promise` that
* eventually resolves to a `Module` object. The returned `Module` must satisfy the
* following two invariants:
*
* * It must belong to the same context as the parent `Module`.
* * Its `status` must not be `'errored'`.
*
* If the returned `Module`'s `status` is `'unlinked'`, this method will be
* recursively called on the returned `Module` with the same provided `linker` function.
*
* `link()` returns a `Promise` that will either get resolved when all linking
* instances resolve to a valid `Module`, or rejected if the linker function either
* throws an exception or returns an invalid `Module`.
*
* The linker function roughly corresponds to the implementation-defined [HostResolveImportedModule](https://tc39.es/ecma262/#sec-hostresolveimportedmodule) abstract operation in the
* ECMAScript
* specification, with a few key differences:
*
* * The linker function is allowed to be asynchronous while [HostResolveImportedModule](https://tc39.es/ecma262/#sec-hostresolveimportedmodule) is synchronous.
*
* The actual [HostResolveImportedModule](https://tc39.es/ecma262/#sec-hostresolveimportedmodule) implementation used during module
* linking is one that returns the modules linked during linking. Since at
* that point all modules would have been fully linked already, the [HostResolveImportedModule](https://tc39.es/ecma262/#sec-hostresolveimportedmodule) implementation is fully synchronous per
* specification.
*
* Corresponds to the [Link() concrete method](https://tc39.es/ecma262/#sec-moduledeclarationlinking) field of [Cyclic Module Record](https://tc39.es/ecma262/#sec-cyclic-module-records) s in
* the ECMAScript specification.
*/
link(linker: ModuleLinker): Promise<void>;
}
interface SourceTextModuleOptions {
/**
* String used in stack traces.
* @default 'vm:module(i)' where i is a context-specific ascending index.
*/
identifier?: string | undefined;
cachedData?: ScriptOptions["cachedData"] | undefined;
context?: Context | undefined;
lineOffset?: BaseOptions["lineOffset"] | undefined;
columnOffset?: BaseOptions["columnOffset"] | undefined;
/**
* Called during evaluation of this module to initialize the `import.meta`.
*/
initializeImportMeta?: ((meta: ImportMeta, module: SourceTextModule) => void) | undefined;
importModuleDynamically?: ScriptOptions["importModuleDynamically"] | undefined;
}
/**
* This feature is only available with the `--experimental-vm-modules` command
* flag enabled.
*
* The `vm.SourceTextModule` class provides the [Source Text Module Record](https://tc39.es/ecma262/#sec-source-text-module-records) as
* defined in the ECMAScript specification.
* @since v9.6.0
* @experimental
*/
class SourceTextModule extends Module {
/**
* Creates a new `SourceTextModule` instance.
* @param code JavaScript Module code to parse
*/
constructor(code: string, options?: SourceTextModuleOptions);
}
interface SyntheticModuleOptions {
/**
* String used in stack traces.
* @default 'vm:module(i)' where i is a context-specific ascending index.
*/
identifier?: string | undefined;
/**
* The contextified object as returned by the `vm.createContext()` method, to compile and evaluate this module in.
*/
context?: Context | undefined;
}
/**
* This feature is only available with the `--experimental-vm-modules` command
* flag enabled.
*
* The `vm.SyntheticModule` class provides the [Synthetic Module Record](https://heycam.github.io/webidl/#synthetic-module-records) as
* defined in the WebIDL specification. The purpose of synthetic modules is to
* provide a generic interface for exposing non-JavaScript sources to ECMAScript
* module graphs.
*
* ```js
* const vm = require('node:vm');
*
* const source = '{ "a": 1 }';
* const module = new vm.SyntheticModule(['default'], function() {
* const obj = JSON.parse(source);
* this.setExport('default', obj);
* });
*
* // Use `module` in linking...
* ```
* @since v13.0.0, v12.16.0
* @experimental
*/
class SyntheticModule extends Module {
/**
* Creates a new `SyntheticModule` instance.
* @param exportNames Array of names that will be exported from the module.
* @param evaluateCallback Called when the module is evaluated.
*/
constructor(
exportNames: string[],
evaluateCallback: (this: SyntheticModule) => void,
options?: SyntheticModuleOptions,
);
/**
* This method is used after the module is linked to set the values of exports. If
* it is called before the module is linked, an `ERR_VM_MODULE_STATUS` error
* will be thrown.
*
* ```js
* import vm from 'node:vm';
*
* const m = new vm.SyntheticModule(['x'], () => {
* m.setExport('x', 1);
* });
*
* await m.link(() => {});
* await m.evaluate();
*
* assert.strictEqual(m.namespace.x, 1);
* ```
* @since v13.0.0, v12.16.0
* @param name Name of the export to set.
* @param value The value to set the export to.
*/
setExport(name: string, value: any): void;
}
/**
* Returns an object containing commonly used constants for VM operations.
* @since v20.12.0
*/
namespace constants {
/**
* Stability: 1.1 - Active development
*
* A constant that can be used as the `importModuleDynamically` option to `vm.Script`
* and `vm.compileFunction()` so that Node.js uses the default ESM loader from the main
* context to load the requested module.
*
* For detailed information, see [Support of dynamic `import()` in compilation APIs](https://nodejs.org/docs/latest-v22.x/api/vm.html#support-of-dynamic-import-in-compilation-apis).
*/
const USE_MAIN_CONTEXT_DEFAULT_LOADER: number;
}
}
declare module "node:vm" {
export * from "vm";
}