// Copyright 2018-2024 the Deno authors. All rights reserved. MIT license. import { assertEquals, assertThrows, fail } from "@std/assert/mod.ts"; import { ftruncate, ftruncateSync } 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' ftruncate(123, 0); }, Error, "No callback function supplied", ); }, }); Deno.test({ name: "ASYNC: truncate entire file contents", async fn() { const filePath = Deno.makeTempFileSync(); await Deno.writeTextFile(filePath, "hello world"); using file = await Deno.open(filePath, { read: true, write: true, create: true, }); await new Promise((resolve, reject) => { ftruncate(file.rid, (err: Error | null) => { if (err !== null) reject(); else resolve(); }); }) .then( () => { const fileInfo: Deno.FileInfo = Deno.lstatSync(filePath); assertEquals(fileInfo.size, 0); }, () => { fail("No error expected"); }, ) .finally(() => { Deno.removeSync(filePath); }); }, }); Deno.test({ name: "ASYNC: truncate file to a size of precisely len bytes", async fn() { const filePath = Deno.makeTempFileSync(); await Deno.writeTextFile(filePath, "hello world"); using file = await Deno.open(filePath, { read: true, write: true, create: true, }); await new Promise((resolve, reject) => { ftruncate(file.rid, 3, (err: Error | null) => { if (err !== null) reject(); else resolve(); }); }) .then( () => { const fileInfo: Deno.FileInfo = Deno.lstatSync(filePath); assertEquals(fileInfo.size, 3); }, () => { fail("No error expected"); }, ) .finally(() => { Deno.removeSync(filePath); }); }, }); Deno.test({ name: "SYNC: truncate entire file contents", fn() { const filePath = Deno.makeTempFileSync(); Deno.writeFileSync(filePath, new TextEncoder().encode("hello world")); using file = Deno.openSync(filePath, { read: true, write: true, create: true, }); try { ftruncateSync(file.rid); const fileInfo: Deno.FileInfo = Deno.lstatSync(filePath); assertEquals(fileInfo.size, 0); } finally { Deno.removeSync(filePath); } }, }); Deno.test({ name: "SYNC: truncate file to a size of precisely len bytes", fn() { const filePath = Deno.makeTempFileSync(); Deno.writeFileSync(filePath, new TextEncoder().encode("hello world")); using file = Deno.openSync(filePath, { read: true, write: true, create: true, }); try { ftruncateSync(file.rid, 3); const fileInfo: Deno.FileInfo = Deno.lstatSync(filePath); assertEquals(fileInfo.size, 3); } finally { Deno.removeSync(filePath); } }, });