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commit 29e9946123fa46a8d7e9b3a74605e0d5431b8b1d
parent d4bd0ee81170c02c0adca39e28726330c50b47c5
Author: Aurimas Vinckevicius <aurimas.dev@gmail.com>
Date:   Sun,  2 Nov 2014 13:47:52 -0600

Allow to define properties for late initialization via defineProperty

Diffstat:
M
chrome/content/zotero/xpcom/zotero.js
 | 
18
+++++++++++++++++-

1 file changed, 17 insertions(+), 1 deletion(-)
diff --git a/chrome/content/zotero/xpcom/zotero.js b/chrome/content/zotero/xpcom/zotero.js
@@ -1407,14 +1407,30 @@ Components.utils.import("resource://gre/modules/osfile.jsm");
 	 * @param {Object} obj Target object
 	 * @param {String} prop Property to be defined
 	 * @param {Object} desc Propery descriptor. If not overriden, "enumerable" is true
+	 * @param {Object} opts Options:
+	 *   lazy {Boolean} If true, the _getter_ is intended for late
+	 *     initialization of the property. The getter is replaced with a simple
+	 *     property once initialized.
 	 */
-	this.defineProperty = function(obj, prop, desc) {
+	this.defineProperty = function(obj, prop, desc, opts) {
 		if (typeof prop != 'string') throw new Error("Property must be a string");
 		var d = { __proto__: null, enumerable: true }; // Enumerable by default
 		for (let p in desc) {
 			if (!desc.hasOwnProperty(p)) continue;
 			d[p] = desc[p];
 		}
+		
+		if (opts) {
+			if (opts.lazy && d.get) {
+				let getter = d.get;
+				d.get = function() {
+					var val = getter.call(this);
+					this[prop] = val; // Replace getter with value
+					return val;
+				}
+			}
+		}
+		
 		Object.defineProperty(obj, prop, d);
 	}