fs: validate args of truncate functions in js

This patch

 1. moves the basic validation of arguments to `truncate` family
    of functions to the JavaScript layer from the C++ layer.

 2. makes sure that the File Descriptors are validated strictly.

PR-URL: https://github.com/nodejs/node/pull/2498
Reviewed-By: Trevor Norris <trev.norris@gmail.com>

1 files changed, 63 insertions, 13 deletions

diff --git a/test/parallel/test-fs-truncate-fd.js b/test/parallel/test-fs-truncate-fd.js
index 2514b80f09..29b03284a2 100644
--- a/test/parallel/test-fs-truncate-fd.js
+++ b/test/parallel/test-fs-truncate-fd.js
@@ -1,21 +1,71 @@
 'use strict';
-var common = require('../common');
-var assert = require('assert');
-var path = require('path');
-var fs = require('fs');
-var tmp = common.tmpDir;
+const common = require('../common');
+const assert = require('assert');
+const fs = require('fs');
+const path = require('path');
+
 common.refreshTmpDir();
-var filename = path.resolve(tmp, 'truncate-file.txt');
+const fds = [];
 
+const filename = path.resolve(common.tmpDir, 'truncate-file.txt');
 fs.writeFileSync(filename, 'hello world', 'utf8');
-var fd = fs.openSync(filename, 'r+');
+const fd = fs.openSync(filename, 'r+');
+fds.push(fd);
 fs.truncate(fd, 5, common.mustCall(function(err) {
-  assert.ok(!err);
+  assert.ifError(err);
   assert.equal(fs.readFileSync(filename, 'utf8'), 'hello');
 }));
 
-process.on('exit', function() {
-  fs.closeSync(fd);
-  fs.unlinkSync(filename);
-  console.log('ok');
-});
+{
+  // test partial truncation of a file
+  const fileName = path.resolve(common.tmpDir, 'truncate-file-1.txt');
+  console.log(fileName);
+  fs.writeFileSync(fileName, 'hello world', 'utf8');
+  const fd = fs.openSync(fileName, 'r+');
+  fds.push(fd);
+
+  fs.truncate(fd, 5, common.mustCall(function(err) {
+    assert.ifError(err);
+    assert.strictEqual(fs.readFileSync(fileName, 'utf8'), 'hello');
+  }));
+}
+
+{
+  // make sure numbers as strings are not treated as fds with sync version
+  const fileName = path.resolve(common.tmpDir, 'truncate-file-2.txt');
+  console.log(fileName);
+  fs.writeFileSync(fileName, 'One');
+  const fd = fs.openSync(fileName, 'r');
+  fds.push(fd);
+
+  const fdFileName = path.resolve(common.tmpDir, '' + fd);
+  fs.writeFileSync(fdFileName, 'Two');
+  assert.strictEqual(fs.readFileSync(fileName).toString(), 'One');
+  assert.strictEqual(fs.readFileSync(fdFileName).toString(), 'Two');
+
+  fs.truncateSync(fdFileName);
+  assert.strictEqual(fs.readFileSync(fileName).toString(), 'One');
+  assert.strictEqual(fs.readFileSync(fdFileName).toString(), '');
+}
+
+{
+  // make sure numbers as strings are not treated as fds with async version
+  const fileName = path.resolve(common.tmpDir, 'truncate-file-3.txt');
+  console.log(fileName);
+  fs.writeFileSync(fileName, 'One');
+  const fd = fs.openSync(fileName, 'r');
+  fds.push(fd);
+
+  const fdFileName = path.resolve(common.tmpDir, '' + fd);
+  fs.writeFileSync(fdFileName, 'Two');
+  assert.strictEqual(fs.readFileSync(fileName).toString(), 'One');
+  assert.strictEqual(fs.readFileSync(fdFileName).toString(), 'Two');
+
+  fs.truncate(fdFileName, common.mustCall(function(err) {
+    assert.ifError(err);
+    assert.strictEqual(fs.readFileSync(fileName).toString(), 'One');
+    assert.strictEqual(fs.readFileSync(fdFileName).toString(), '');
+  }));
+}
+
+process.on('exit', () => fds.forEach((fd) => fs.closeSync(fd)));