// Copyright 2018-2024 the Deno authors. All rights reserved. MIT license. import { assertEquals, assertThrows, fail } from "@std/assert"; import { truncate, truncateSync } from "node:fs"; Deno.test({ name: "ASYNC: no callback function results in Error", fn() { assertThrows( () => { // @ts-expect-error Argument of type 'number' is not assignable to parameter of type 'NoParamCallback' truncate("some/path", 0); }, Error, "No callback function supplied", ); }, }); Deno.test({ name: "ASYNC: truncate entire file contents", async fn() { const file: string = Deno.makeTempFileSync(); await Deno.writeTextFile(file, "hello world"); await new Promise((resolve, reject) => { truncate(file, (err: Error | null) => { if (err !== null) reject(); else resolve(); }); }) .then( () => { const fileInfo: Deno.FileInfo = Deno.lstatSync(file); assertEquals(fileInfo.size, 0); }, () => { fail("No error expected"); }, ) .finally(() => Deno.removeSync(file)); }, }); Deno.test({ name: "ASYNC: truncate file to a size of precisely len bytes", async fn() { const file: string = Deno.makeTempFileSync(); await Deno.writeTextFile(file, "hello world"); await new Promise((resolve, reject) => { truncate(file, 3, (err: Error | null) => { if (err !== null) reject(); else resolve(); }); }) .then( () => { const fileInfo: Deno.FileInfo = Deno.lstatSync(file); assertEquals(fileInfo.size, 3); }, () => { fail("No error expected"); }, ) .finally(() => Deno.removeSync(file)); }, }); Deno.test({ name: "SYNC: truncate entire file contents", fn() { const file: string = Deno.makeTempFileSync(); try { truncateSync(file); const fileInfo: Deno.FileInfo = Deno.lstatSync(file); assertEquals(fileInfo.size, 0); } finally { Deno.removeSync(file); } }, }); Deno.test({ name: "SYNC: truncate file to a size of precisely len bytes", fn() { const file: string = Deno.makeTempFileSync(); try { truncateSync(file, 3); const fileInfo: Deno.FileInfo = Deno.lstatSync(file); assertEquals(fileInfo.size, 3); } finally { Deno.removeSync(file); } }, });