Fix #523: added tests for fs.ftruncate() (#524)

* Fix #523: added tests for fs.ftruncate()

* fix #523: moved a function from truncate to ftruncate and made a few minor changes

* Fixed indentation

tests/index.js

@@ -29,6 +29,7 @@ require('./spec/fs.lseek.spec');
 require('./spec/fs.symlink.spec');
 require('./spec/fs.readlink.spec');
 require('./spec/fs.truncate.spec');
+require('./spec/fs.ftruncate.spec');
 require('./spec/fs.utimes.spec');
 require('./spec/fs.xattr.spec');
 require('./spec/fs.stats.spec');

tests/spec/fs.ftruncate.spec.js

@@ -0,0 +1,133 @@
+const util = require('../lib/test-utils.js');
+const expect = require('chai').expect;
+
+describe('fs.ftruncate', function() {
+  beforeEach(util.setup);
+  afterEach(util.cleanup);
+
+  it('should be a function', function() {
+    let fs = util.fs();
+    expect(fs.ftruncate).to.be.a('function');
+  });
+
+  it('should return an error if length is negative', function(done) {
+    let fs = util.fs();
+    let contents = 'This is a file.';
+
+    fs.writeFile('/myfile', contents, function(error) {
+      if(error) throw error;
+
+      fs.open('/myfile', 'w', function(err, fd) {
+
+        fs.ftruncate(fd, -1, function(error) {
+          expect(error).to.exist;
+          expect(error.code).to.equal('EINVAL');
+          done();
+        });
+
+        // Close file descriptor when done
+        fs.close(fd);
+      });
+    });
+  });
+
+  it('should return an error if file descriptor is negative', function(done) {
+    let fs = util.fs();
+
+    // File descriptor should be a non-negative number
+    fs.ftruncate(-1, 0, function(error) {
+      expect(error).to.exist;
+      expect(error.code).to.equal('EBADF');
+      done();
+    });
+  });
+
+  it('should truncate a file', function(done) {
+    let fs = util.fs();
+    let buffer = new Buffer([1, 2, 3, 4, 5, 6, 7, 8]);
+    let truncated = new Buffer([1, 2]);
+
+    fs.open('/myfile', 'w', function(error, result) {
+      if(error) throw error;
+      let fd = result;
+
+      fs.write(fd, buffer, 0, buffer.length, 0, function(error, result) {
+        if(error) throw error;
+        expect(result).to.equal(buffer.length);
+
+        // Truncate file to first two bytes
+        fs.ftruncate(fd, 2, function(error) {
+          expect(error).not.to.exist;
+        });
+
+        fs.close(fd, function(error) {
+          if(error) throw error;
+
+          fs.readFile('/myfile', function(error, result) {
+            if(error) throw error;
+
+            expect(result).to.deep.equal(truncated);
+            done();
+          });
+        });
+      });
+    });
+  });
+
+  it('should truncate a valid descriptor', 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.ftruncate(fd, 0, function(error) {
+          expect(error).not.to.exist;
+
+          fs.fstat(fd, function(error, result) {
+            if(error) throw error;
+
+            expect(result.size).to.equal(0);
+            done();
+          });
+        });
+      });
+    });
+  });
+
+  it('should pad a file with zeros when the length is greater than the file size', function(done) {
+    let fs = util.fs();
+    let buffer = new Buffer([1, 2, 3, 4, 5, 6, 7, 8]);
+    let truncated = new Buffer([1, 2, 3, 4, 5, 6, 7, 8, 0]);
+
+    fs.open('/myfile', 'w', function(error, result) {
+      if(error) throw error;
+
+      let fd = result;
+      fs.write(fd, buffer, 0, buffer.length, 0, function(error, result) {
+        if(error) throw error;
+        expect(result).to.equal(buffer.length);
+
+        fs.ftruncate(fd, 9, function(error) {
+          expect(error).not.to.exist;
+        });
+
+        fs.close(fd, function(error) {
+          if(error) throw error;
+
+          fs.readFile('/myfile', function(error, result) {
+            if(error) throw error;
+
+            expect(result).to.deep.equal(truncated);
+            done();
+          });
+        });
+      });
+    });
+  });
+});

tests/spec/fs.truncate.spec.js

@@ -173,32 +173,6 @@ describe('fs.truncate', function() {
     });
   });
 
-  it('should truncate a valid descriptor', 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.ftruncate(fd, 0, function(error) {
-          expect(error).not.to.exist;
-
-          fs.fstat(fd, 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]);