fs: expose Stats times as Numbers

PR-URL: https://github.com/nodejs/node/pull/13173
Fixes: https://github.com/nodejs/node/issues/8276
Refs: https://github.com/nodejs/node/pull/12607
Refs: https://github.com/nodejs/node/pull/12818
Reviewed-By: Anna Henningsen <anna@addaleax.net>
Reviewed-By: Brian White <mscdex@mscdex.net>

3 files changed, 59 insertions, 30 deletions

diff --git a/doc/api/fs.md b/doc/api/fs.md
index 5361f06f20..1decabbc39 100644
--- a/doc/api/fs.md
+++ b/doc/api/fs.md
@@ -301,10 +301,14 @@ argument to `fs.createReadStream()`. If `path` is passed as a string, then
 ## Class: fs.Stats
 <!-- YAML
 added: v0.1.21
+changes:
+  - version: REPLACEME
+    pr-url: https://github.com/nodejs/node/pull/13173
+    description: Added times as numbers.
 -->
 
-Objects returned from [`fs.stat()`][], [`fs.lstat()`][] and [`fs.fstat()`][] and their
-synchronous counterparts are of this type.
+Objects returned from [`fs.stat()`][], [`fs.lstat()`][] and [`fs.fstat()`][] and
+their synchronous counterparts are of this type.
 
  - `stats.isFile()`
  - `stats.isDirectory()`
@@ -329,20 +333,23 @@ Stats {
   size: 527,
   blksize: 4096,
   blocks: 8,
+  atimeMs: 1318289051000.1,
+  mtimeMs: 1318289051000.1,
+  ctimeMs: 1318289051000.1,
+  birthtimeMs: 1318289051000.1,
   atime: Mon, 10 Oct 2011 23:24:11 GMT,
   mtime: Mon, 10 Oct 2011 23:24:11 GMT,
   ctime: Mon, 10 Oct 2011 23:24:11 GMT,
   birthtime: Mon, 10 Oct 2011 23:24:11 GMT }
 ```
 
-Please note that `atime`, `mtime`, `birthtime`, and `ctime` are
-instances of [`Date`][MDN-Date] object and appropriate methods should be used
-to compare the values of these objects. For most general uses
-[`getTime()`][MDN-Date-getTime] will return the number of milliseconds elapsed
-since _1 January 1970 00:00:00 UTC_ and this integer should be sufficient for
-any comparison, however there are additional methods which can be used for
-displaying fuzzy information. More details can be found in the
-[MDN JavaScript Reference][MDN-Date] page.
+*Note*: `atimeMs`, `mtimeMs`, `ctimeMs`, `birthtimeMs` are [numbers][MDN-Number]
+that hold the corresponding times in milliseconds. Their precision is platform
+specific. `atime`, `mtime`, `ctime`, and `birthtime` are [`Date`][MDN-Date]
+object alternate representations of the various times. The `Date` and number
+values are not connected. Assigning a new number value, or mutating the `Date`
+value, will not be reflected in the corresponding alternate representation.
+
 
 ### Stat Time Values
 
@@ -2841,6 +2848,7 @@ The following constants are meant for use with the [`fs.Stats`][] object's
 [FS Constants]: #fs_fs_constants_1
 [MDN-Date-getTime]: https://developer.mozilla.org/en/JavaScript/Reference/Global_Objects/Date/getTime
 [MDN-Date]: https://developer.mozilla.org/en/JavaScript/Reference/Global_Objects/Date
+[MDN-Number]: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Number_type
 [MSDN-Rel-Path]: https://msdn.microsoft.com/en-us/library/windows/desktop/aa365247.aspx#fully_qualified_vs._relative_paths
 [Readable Stream]: stream.html#stream_class_stream_readable
 [Writable Stream]: stream.html#stream_class_stream_writable
diff --git a/lib/fs.js b/lib/fs.js
index 5242c90925..6273c975c1 100644
--- a/lib/fs.js
+++ b/lib/fs.js
@@ -196,6 +196,10 @@ function Stats(
   this.ino = ino;
   this.size = size;
   this.blocks = blocks;
+  this.atimeMs = atim_msec;
+  this.mtimeMs = mtim_msec;
+  this.ctimeMs = ctim_msec;
+  this.birthtimeMs = birthtim_msec;
   this.atime = new Date(atim_msec + 0.5);
   this.mtime = new Date(mtim_msec + 0.5);
   this.ctime = new Date(ctim_msec + 0.5);
diff --git a/test/parallel/test-fs-stat.js b/test/parallel/test-fs-stat.js
index 6ed27806b9..c12af535fa 100644
--- a/test/parallel/test-fs-stat.js
+++ b/test/parallel/test-fs-stat.js
@@ -65,38 +65,55 @@ fs.open('.', 'r', undefined, common.mustCall(function(err, fd) {
     assert.fail(err);
   }
   if (stats) {
-    console.dir(stats);
     assert.ok(stats.mtime instanceof Date);
   }
   fs.close(fd, assert.ifError);
 }));
 
-console.log(`stating:  ${__filename}`);
 fs.stat(__filename, common.mustCall(function(err, s) {
   assert.ifError(err);
-
-  console.dir(s);
-
-  console.log(`isDirectory: ${JSON.stringify(s.isDirectory())}`);
   assert.strictEqual(false, s.isDirectory());
-
-  console.log(`isFile: ${JSON.stringify(s.isFile())}`);
   assert.strictEqual(true, s.isFile());
-
-  console.log(`isSocket: ${JSON.stringify(s.isSocket())}`);
   assert.strictEqual(false, s.isSocket());
-
-  console.log(`isBlockDevice: ${JSON.stringify(s.isBlockDevice())}`);
   assert.strictEqual(false, s.isBlockDevice());
-
-  console.log(`isCharacterDevice: ${JSON.stringify(s.isCharacterDevice())}`);
   assert.strictEqual(false, s.isCharacterDevice());
-
-  console.log(`isFIFO: ${JSON.stringify(s.isFIFO())}`);
   assert.strictEqual(false, s.isFIFO());
-
-  console.log(`isSymbolicLink: ${JSON.stringify(s.isSymbolicLink())}`);
   assert.strictEqual(false, s.isSymbolicLink());
-
-  assert.ok(s.mtime instanceof Date);
+  const keys = [
+    'dev', 'mode', 'nlink', 'uid',
+    'gid', 'rdev', 'ino', 'size',
+    'atime', 'mtime', 'ctime', 'birthtime',
+    'atimeMs', 'mtimeMs', 'ctimeMs', 'birthtimeMs'
+  ];
+  if (!common.isWindows) {
+    keys.push('blocks', 'blksize');
+  }
+  const numberFields = [
+    'dev', 'mode', 'nlink', 'uid', 'gid', 'rdev', 'ino', 'size',
+    'atimeMs', 'mtimeMs', 'ctimeMs', 'birthtimeMs'
+  ];
+  const dateFields = ['atime', 'mtime', 'ctime', 'birthtime'];
+  keys.forEach(function(k) {
+    assert.ok(k in s, `${k} should be in Stats`);
+    assert.notStrictEqual(s[k], undefined, `${k} should not be undefined`);
+    assert.notStrictEqual(s[k], null, `${k} should not be null`);
+  });
+  numberFields.forEach((k) => {
+    assert.strictEqual(typeof s[k], 'number', `${k} should be a number`);
+  });
+  dateFields.forEach((k) => {
+    assert.ok(s[k] instanceof Date, `${k} should be a Date`);
+  });
+  const jsonString = JSON.stringify(s);
+  const parsed = JSON.parse(jsonString);
+  keys.forEach(function(k) {
+    assert.notStrictEqual(parsed[k], undefined, `${k} should not be undefined`);
+    assert.notStrictEqual(parsed[k], null, `${k} should not be null`);
+  });
+  numberFields.forEach((k) => {
+    assert.strictEqual(typeof parsed[k], 'number', `${k} should be a number`);
+  });
+  dateFields.forEach((k) => {
+    assert.strictEqual(typeof parsed[k], 'string', `${k} should be a string`);
+  });
 }));