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// Copyright 2018-2023 the Deno authors. All rights reserved. MIT license.
import { assert, assertStringIncludes } from "../testing/asserts.ts";
/** Asserts that an error thrown in a callback will not be wrongly caught. */export async function assertCallbackErrorUncaught( { prelude, invocation, cleanup }: { /** Any code which needs to run before the actual invocation (notably, any import statements). */ prelude?: string; /** * The start of the invocation of the function, e.g. `open("foo.txt", `. * The callback will be added after it. */ invocation: string; /** Called after the subprocess is finished but before running the assertions, e.g. to clean up created files. */ cleanup?: () => Promise<void> | void; },) { // Since the error has to be uncaught, and that will kill the Deno process, // the only way to test this is to spawn a subprocess. const p = new Deno.Command(Deno.execPath(), { args: [ "eval", "--unstable", `${prelude ?? ""} ${invocation}(err) => { // If the bug is present and the callback is called again with an error, // don't throw another error, so if the subprocess fails we know it had the correct behaviour. if (!err) throw new Error("success"); });`, ], stderr: "piped", }); const { stderr, success } = await p.output(); const error = new TextDecoder().decode(stderr); await cleanup?.(); assert(!success); assertStringIncludes(error, "Error: success");}