src,fs: calculate times as unsigned long

PR-URL: #13281
Fixes: #13255
Reviewed-By: Anna Henningsen <anna@addaleax.net>
Reviewed-By: James M Snell <jasnell@gmail.com>

src/node_file.cc

@@ -478,10 +478,13 @@ void FillStatsArray(double* fields, const uv_stat_t* s) {
 #else
   fields[9] = -1;
 #endif
-  // Dates.
-#define X(idx, name)                          \
-  fields[idx] = (s->st_##name.tv_sec * 1e3) + \
-                (s->st_##name.tv_nsec / 1e6); \
+// Dates.
+// NO-LINT because the fields are 'long' and we just want to cast to `unsigned`
+#define X(idx, name)                                           \
+  /* NOLINTNEXTLINE(runtime/int) */                            \
+  fields[idx] = ((unsigned long)(s->st_##name.tv_sec) * 1e3) + \
+  /* NOLINTNEXTLINE(runtime/int) */                            \
+                ((unsigned long)(s->st_##name.tv_nsec) / 1e6); \
 
   X(10, atim)
   X(11, mtim)

test/parallel/test-fs-utimes.js

@@ -163,8 +163,40 @@ runTest(new Date('1982-09-10 13:37'), new Date('1982-09-10 13:37'), function() {
   });
 });
 
-
 process.on('exit', function() {
-  console.log('Tests run / ok:', tests_run, '/', tests_ok);
   assert.strictEqual(tests_ok, tests_run);
 });
+
+
+// Ref: https://github.com/nodejs/node/issues/13255
+common.refreshTmpDir();
+const path = `${common.tmpDir}/test-utimes-precision`;
+fs.writeFileSync(path, '');
+
+// test Y2K38 for all platforms [except 'arm', and 'SunOS']
+if (!process.arch.includes('arm') && !common.isSunOS) {
+  // because 2 ** 31 doesn't look right
+  // eslint-disable-next-line space-infix-ops
+  const Y2K38_mtime = 2**31;
+  fs.utimesSync(path, Y2K38_mtime, Y2K38_mtime);
+  const Y2K38_stats = fs.statSync(path);
+  assert.strictEqual(Y2K38_mtime, Y2K38_stats.mtime.getTime() / 1000);
+}
+
+if (common.isWindows) {
+  // this value would get converted to (double)1713037251359.9998
+  const truncate_mtime = 1713037251360;
+  fs.utimesSync(path, truncate_mtime / 1000, truncate_mtime / 1000);
+  const truncate_stats = fs.statSync(path);
+  assert.strictEqual(truncate_mtime, truncate_stats.mtime.getTime());
+
+  // test Y2K38 for windows
+  // This value if treaded as a `signed long` gets converted to -2135622133469.
+  // POSIX systems stores timestamps in {long t_sec, long t_usec}.
+  // NTFS stores times in nanoseconds in a single `uint64_t`, so when libuv
+  // calculates (long)`uv_timespec_t.tv_sec` we get 2's complement.
+  const overflow_mtime = 2159345162531;
+  fs.utimesSync(path, overflow_mtime / 1000, overflow_mtime / 1000);
+  const overflow_stats = fs.statSync(path);
+  assert.strictEqual(overflow_mtime, overflow_stats.mtime.getTime());
+}