fixed range formatting

lib/single-file/fonts-minifier.js

@@ -113,7 +113,7 @@ this.fontsMinifier = this.fontsMinifier || (() => {
 				const range = rangeValue.split(/-/);
 				if (range.length == 2) {
 					range[0] = transformRange(range[0]);
-					const regExpString = "[" + range[0] + "-\\u" + range[1] + "]";
+					const regExpString = "[" + range[0] + "-" + transformRange("U+" + range[1]) + "]";
 					return (new RegExp(regExpString)).test(docContent);
 				}
 				if (range.length == 1) {
@@ -136,7 +136,11 @@ this.fontsMinifier = this.fontsMinifier || (() => {
 	}
 
 	function transformRange(range) {
-		return range.replace(/^U\+/i, "\\u");
+		range = range.replace(/^U\+/i, "");
+		while (range.length < 4) {
+			range = "0" + range;
+		}
+		return "\\u" + range;
 	}
 
 	function processFontFaceRule(rule, fontSources, stats) {