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ShellPromise

Bun

Symbol

$.ShellPromise

  • readonly [Symbol.toStringTag]: string

  • Read from stdout as an ArrayBuffer

    Automatically calls quiet

    @returns

    A promise that resolves with stdout as an ArrayBuffer

    const output = await $`echo hello`.arrayBuffer();
console.log(output); // ArrayBuffer { byteLength: 6 }
  • blob(): Promise<Blob>

    Read from stdout as a Blob

    Automatically calls quiet

    @returns

    A promise that resolves with stdout as a Blob

    const output = await $`echo hello`.blob();
console.log(output); // Blob { size: 6, type: "" }
  • catch<TResult = never>(onrejected?: null | (reason: any) => TResult | PromiseLike<TResult>): Promise<ShellOutput | TResult>

    Attaches a callback for only the rejection of the Promise.

    @param onrejected

    The callback to execute when the Promise is rejected.

    @returns

    A Promise for the completion of the callback.

  • cwd(newCwd: string): this

    Change the current working directory of the shell.

    @param newCwd

    The new working directory

  • env(newEnv: undefined | Record<string, string>): this

    Set environment variables for the shell.

    @param newEnv

    The new environment variables

    await $`echo $FOO`.env({ ...process.env, FOO: "LOL!" })
expect(stdout.toString()).toBe("LOL!");
  • finally(onfinally?: null | () => void): Promise<ShellOutput>

    Attaches a callback that is invoked when the Promise is settled (fulfilled or rejected). The resolved value cannot be modified from the callback.

    @param onfinally

    The callback to execute when the Promise is settled (fulfilled or rejected).

    @returns

    A Promise for the completion of the callback.

  • json(): Promise<any>

    Read from stdout as a JSON object

    Automatically calls quiet

    @returns

    A promise that resolves with stdout as a JSON object

    const output = await $`echo '{"hello": 123}'`.json();
console.log(output); // { hello: 123 }
  • lines(): AsyncIterable<string>

    Read from stdout as a string, line by line

    Automatically calls quiet to disable echoing to stdout.

  • nothrow(): this

    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.

  • quiet(): this

    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.

  • text(encoding?: BufferEncoding): Promise<string>

    Read from stdout as a string

    Automatically calls quiet to disable echoing to stdout.

    @param encoding

    The encoding to use when decoding the output

    @returns

    A 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 onfulfilled

    The callback to execute when the Promise is resolved.

    @param onrejected

    The callback to execute when the Promise is rejected.

    @returns

    A Promise for the completion of which ever callback is executed.

  • throws(shouldThrow: boolean): this

    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 values

    An array of Promises.

    @returns

    A 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 values

    An array of Promises.

    @returns

    A new Promise.

  • static any<T extends readonly unknown[] | []>(values: T): Promise<Awaited<T[number]>>

    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 values

    An array or iterable of Promises.

    @returns

    A new Promise.

  • static race<T extends readonly unknown[] | []>(values: T): Promise<Awaited<T[number]>>

    Creates a Promise that is resolved or rejected when any of the provided Promises are resolved or rejected.

    @param values

    An array of Promises.

    @returns

    A new Promise.

  • static reject<T = never>(reason?: any): Promise<T>

    Creates a new rejected promise for the provided reason.

    @param reason

    The reason the promise was rejected.

    @returns

    A new rejected Promise.

  • static resolve<T>(value: T): Promise<Awaited<T>>

    Creates a new resolved promise for the provided value.

    @param value

    A promise.

    @returns

    A promise whose internal state matches the provided promise.

  • static try<T, A extends any[] = []>(fn: (...args: A) => T | PromiseLike<T>, ...args: A): Promise<T>

    Try to run a function and return the result. If the function throws, return the result of the catch function.

    @param fn

    The function to run

    @param args

    The arguments to pass to the function. This is similar to setTimeout and avoids the extra closure.

    @returns

    The 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 and reject 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.