bug fix and performance improvements

miniprogram/miniprogram_npm/tdesign-miniprogram/empty/empty.wxs

@@ -0,0 +1,12 @@
+var REGEXP = getRegExp('^\d+(\.\d+)?$');
+
+function addUnit(value) {
+  if (value == null) {
+    return undefined;
+  }
+  return REGEXP.test('' + value) ? value + 'px' : value;
+}
+
+module.exports = {
+  addUnit: addUnit,
+};