var util = require('../lib/test-utils.js'); var expect = require('chai').expect; describe('fs.truncate', function() { beforeEach(util.setup); afterEach(util.cleanup); it('should be a function', function() { var fs = util.fs(); expect(fs.truncate).to.be.a('function'); }); it('should error when length is not an integer', function(done) { var fs = util.fs(); var contents = 'This is a file.'; fs.writeFile('/myfile', contents, function(error) { if(error) throw error; fs.truncate('/myfile', 'notAnInteger', function(error) { expect(error).to.exist; expect(error.code).to.equal('EINVAL'); done(); }); }); }); it('should error when length is negative', function(done) { var fs = util.fs(); var contents = 'This is a file.'; fs.writeFile('/myfile', contents, function(error) { if(error) throw error; fs.truncate('/myfile', -1, function(error) { expect(error).to.exist; expect(error.code).to.equal('EINVAL'); done(); }); }); }); it('should error when path is not a file', function(done) { var fs = util.fs(); fs.truncate('/', 0, function(error) { expect(error).to.exist; expect(error.code).to.equal('EISDIR'); done(); }); }); it('should truncate a file', function(done) { var fs = util.fs(); var buffer = new Buffer([1, 2, 3, 4, 5, 6, 7, 8]); var truncated = new Buffer([1]); fs.open('/myfile', 'w', function(error, result) { if(error) throw error; var fd = result; fs.write(fd, buffer, 0, buffer.length, 0, function(error, result) { if(error) throw error; expect(result).to.equal(buffer.length); fs.close(fd, function(error) { if(error) throw error; fs.truncate('/myfile', 1, function(error) { expect(error).not.to.exist; fs.readFile('/myfile', function(error, result) { if(error) throw error; expect(result).to.deep.equal(truncated); done(); }); }); }); }); }); }); it('should pad a file with zeros when the length is greater than the file size', function(done) { var fs = util.fs(); var buffer = new Buffer([1, 2, 3, 4, 5, 6, 7, 8]); var truncated = new Buffer([1, 2, 3, 4, 5, 6, 7, 8, 0]); fs.open('/myfile', 'w', function(error, result) { if(error) throw error; var fd = result; fs.write(fd, buffer, 0, buffer.length, 0, function(error, result) { if(error) throw error; expect(result).to.equal(buffer.length); fs.close(fd, function(error) { if(error) throw error; fs.truncate('/myfile', 9, function(error) { expect(error).not.to.exist; fs.readFile('/myfile', function(error, result) { if(error) throw error; expect(result).to.deep.equal(truncated); done(); }); }); }); }); }); }); it('should update the file size', function(done) { var fs = util.fs(); var buffer = new Buffer([1, 2, 3, 4, 5, 6, 7, 8]); fs.open('/myfile', 'w', function(error, result) { if(error) throw error; var fd = result; fs.write(fd, buffer, 0, buffer.length, 0, function(error, result) { if(error) throw error; expect(result).to.equal(buffer.length); fs.close(fd, function(error) { if(error) throw error; fs.truncate('/myfile', 0, function(error) { expect(error).not.to.exist; fs.stat('/myfile', function(error, result) { if(error) throw error; expect(result.size).to.equal(0); done(); }); }); }); }); }); }); it('should assume a length of 0 if passed undefined', function(done) { var fs = util.fs(); var buffer = new Buffer([1, 2, 3, 4, 5, 6, 7, 8]); fs.open('/myfile', 'w', function(error, result) { if(error) throw error; var fd = result; fs.write(fd, buffer, 0, buffer.length, 0, function(error, result) { if(error) throw error; expect(result).to.equal(buffer.length); fs.close(fd, function(error) { if(error) throw error; // We want to use undefined to see that it defaults to 0 fs.truncate('/myfile', undefined, function(error) { expect(error).not.to.exist; fs.stat('/myfile', function(error, result) { if(error) throw error; expect(result.size).to.equal(0); done(); }); }); }); }); }); }); it('should follow symbolic links', function(done) { var fs = util.fs(); var buffer = new Buffer([1, 2, 3, 4, 5, 6, 7, 8]); fs.open('/myfile', 'w', function(error, result) { if(error) throw error; var fd = result; fs.write(fd, buffer, 0, buffer.length, 0, function(error, result) { if(error) throw error; expect(result).to.equal(buffer.length); fs.close(fd, function(error) { if(error) throw error; fs.symlink('/myfile', '/mylink', function(error) { if(error) throw error; fs.truncate('/mylink', 0, function(error) { expect(error).not.to.exist; fs.stat('/myfile', function(error, result) { if(error) throw error; expect(result.size).to.equal(0); fs.lstat('/mylink', function(error, result) { if(error) throw error; expect(result.size).not.to.equal(0); done(); }); }); }); }); }); }); }); }); }); describe('fsPromises.truncate', function () { beforeEach(util.setup); afterEach(util.cleanup); it('should error when path does not exist (with promises)', () => { var fsPromises = util.fs().promises; return fsPromises.truncate('/NonExistingPath', 0) .catch(error => { expect(error).to.exist; expect(error.code).to.equal('ENOENT'); }); }); });