Creates a new Promise.
Symbol
$.ShellPromise.constructor
A callback used to initialize the promise. This callback is passed two arguments: a resolve callback used to resolve the promise with a value or the result of another promise, and a reject callback used to reject the promise with a provided reason or error.
Referenced types
class ShellPromise
Read from stdout as an ArrayBuffer
Automatically calls quiet
@returnsA promise that resolves with stdout as an ArrayBuffer
const output = await $`echo hello`.arrayBuffer(); console.log(output); // ArrayBuffer { byteLength: 6 }
- catch<TResult = never>(onrejected?: null | (reason: any) => TResult | PromiseLike<TResult>): Promise<ShellOutput | TResult>
Attaches a callback for only the rejection of the Promise.
@param onrejectedThe callback to execute when the Promise is rejected.
@returnsA Promise for the completion of the callback.
Change the current working directory of the shell.
@param newCwdThe new working directory
Set environment variables for the shell.
@param newEnvThe new environment variables
await $`echo $FOO`.env({ ...process.env, FOO: "LOL!" }) expect(stdout.toString()).toBe("LOL!");
Attaches a callback that is invoked when the Promise is settled (fulfilled or rejected). The resolved value cannot be modified from the callback.
@param onfinallyThe callback to execute when the Promise is settled (fulfilled or rejected).
@returnsA Promise for the completion of the callback.
Read from stdout as a JSON object
Automatically calls quiet
@returnsA promise that resolves with stdout as a JSON object
const output = await $`echo '{"hello": 123}'`.json(); console.log(output); // { hello: 123 }
Read from stdout as a string, line by line
Automatically calls quiet to disable echoing to stdout.
Configure the shell to not throw an exception on non-zero exit codes. Throwing can be re-enabled with
.throws(true)
.By default, the shell with throw an exception on commands which return non-zero exit codes.
By default, the shell will write to the current process's stdout and stderr, as well as buffering that output.
This configures the shell to only buffer the output.
Read from stdout as a string
Automatically calls quiet to disable echoing to stdout.
@param encodingThe encoding to use when decoding the output
@returnsA promise that resolves with stdout as a string
Read as UTF-8 string
const output = await $`echo hello`.text(); console.log(output); // "hello\n"
Read as base64 string
const output = await $`echo ${atob("hello")}`.text("base64"); console.log(output); // "hello\n"
- then<TResult1 = ShellOutput, TResult2 = never>(onfulfilled?: null | (value: ShellOutput) => TResult1 | PromiseLike<TResult1>, onrejected?: null | (reason: any) => TResult2 | PromiseLike<TResult2>): Promise<TResult1 | TResult2>
Attaches callbacks for the resolution and/or rejection of the Promise.
@param onfulfilledThe callback to execute when the Promise is resolved.
@param onrejectedThe callback to execute when the Promise is rejected.
@returnsA Promise for the completion of which ever callback is executed.
Configure whether or not the shell should throw an exception on non-zero exit codes.
By default, this is configured to
true
.- static all<T extends readonly unknown[] | []>(values: T): Promise<{ [K in string | number | symbol]: Awaited<T[P<P>]> }>
Creates a Promise that is resolved with an array of results when all of the provided Promises resolve, or rejected when any Promise is rejected.
@param valuesAn array of Promises.
@returnsA new Promise.
- static allSettled<T>(values: Iterable<T | PromiseLike<T>>): Promise<PromiseSettledResult<Awaited<T>>[]>
Creates a Promise that is resolved with an array of results when all of the provided Promises resolve or reject.
@param valuesAn array of Promises.
@returnsA new Promise.
The any function returns a promise that is fulfilled by the first given promise to be fulfilled, or rejected with an AggregateError containing an array of rejection reasons if all of the given promises are rejected. It resolves all elements of the passed iterable to promises as it runs this algorithm.
@param valuesAn array or iterable of Promises.
@returnsA new Promise.
Creates a Promise that is resolved or rejected when any of the provided Promises are resolved or rejected.
@param valuesAn array of Promises.
@returnsA new Promise.
Creates a new rejected promise for the provided reason.
@param reasonThe reason the promise was rejected.
@returnsA new rejected Promise.
Creates a new resolved promise for the provided value.
@param valueA promise.
@returnsA promise whose internal state matches the provided promise.
Try to run a function and return the result. If the function throws, return the result of the
catch
function.@param fnThe function to run
@param argsThe arguments to pass to the function. This is similar to
setTimeout
and avoids the extra closure.@returnsThe result of the function or the result of the
catch
function- static withResolvers<T>(): { promise: Promise<T>; reject: (reason?: any) => void; resolve: (value?: T | PromiseLike<T>) => void }
Create a deferred promise, with exposed
resolve
andreject
methods which can be called separately.This is useful when you want to return a Promise and have code outside the Promise resolve or reject it.
Example
const { promise, resolve, reject } = Promise.withResolvers(); setTimeout(() => { resolve("Hello world!"); }, 1000); await promise; // "Hello world!"
Promise.withResolvers()
is a stage3 proposal.