fs: make stats date fields lazy

anonrig · anonrig · commit 9708adb54e27 · 2023-11-28T20:18:16.000-05:00
diff --git a/lib/internal/fs/utils.js b/lib/internal/fs/utils.js
@@ -12,6 +12,8 @@ const {
   NumberIsFinite,
   MathMin,
   MathRound,
+  ObjectDefineProperties,
+  ObjectDefineProperty,
   ObjectIs,
   ObjectSetPrototypeOf,
   ReflectApply,
@@ -448,6 +450,62 @@ function dateFromMs(ms) {
   return new Date(MathRound(Number(ms)));
 }
 
+const lazyDateFields = {
+  __proto__: null,
+  atime: {
+    __proto__: null,
+    enumerable: true,
+    configurable: true,
+    get() {
+      const value = dateFromMs(this.atimeMs);
+      ObjectDefineProperty(this, 'atime', { __proto__: null, value });
+      return this.atime;
+    },
+    set(value) {
+      this.atime = value;
+    },
+  },
+  mtime: {
+    __proto__: null,
+    enumerable: true,
+    configurable: true,
+    get() {
+      const value = dateFromMs(this.mtimeMs);
+      ObjectDefineProperty(this, 'mtime', { __proto__: null, value });
+      return this.mtime;
+    },
+    set(value) {
+      this.mtime = value;
+    },
+  },
+  ctime: {
+    __proto__: null,
+    enumerable: true,
+    configurable: true,
+    get() {
+      const value = dateFromMs(this.ctimeMs);
+      ObjectDefineProperty(this, 'ctime', { __proto__: null, value });
+      return this.ctime;
+    },
+    set(value) {
+      this.ctime = value;
+    },
+  },
+  birthtime: {
+    __proto__: null,
+    enumerable: true,
+    configurable: true,
+    get() {
+      const value = dateFromMs(this.birthtimeMs);
+      ObjectDefineProperty(this, 'birthtime', { __proto__: null, value });
+      return this.birthtime;
+    },
+    set(value) {
+      this.birthtime = value;
+    },
+  },
+};
+
 function BigIntStats(dev, mode, nlink, uid, gid, rdev, blksize,
                      ino, size, blocks,
                      atimeNs, mtimeNs, ctimeNs, birthtimeNs) {
@@ -462,10 +520,8 @@ function BigIntStats(dev, mode, nlink, uid, gid, rdev, blksize,
   this.mtimeNs = mtimeNs;
   this.ctimeNs = ctimeNs;
   this.birthtimeNs = birthtimeNs;
-  this.atime = dateFromMs(this.atimeMs);
-  this.mtime = dateFromMs(this.mtimeMs);
-  this.ctime = dateFromMs(this.ctimeMs);
-  this.birthtime = dateFromMs(this.birthtimeMs);
+
+  ObjectDefineProperties(this, lazyDateFields);
 }
 
 ObjectSetPrototypeOf(BigIntStats.prototype, StatsBase.prototype);
@@ -488,10 +544,8 @@ function Stats(dev, mode, nlink, uid, gid, rdev, blksize,
   this.mtimeMs = mtimeMs;
   this.ctimeMs = ctimeMs;
   this.birthtimeMs = birthtimeMs;
-  this.atime = dateFromMs(atimeMs);
-  this.mtime = dateFromMs(mtimeMs);
-  this.ctime = dateFromMs(ctimeMs);
-  this.birthtime = dateFromMs(birthtimeMs);
+
+  ObjectDefineProperties(this, lazyDateFields);
 }
 
 ObjectSetPrototypeOf(Stats.prototype, StatsBase.prototype);
