1 files changed, 40 insertions, 0 deletions
diff --git a/devtools/client/shared/classnames.js b/devtools/client/shared/classnames.js
new file mode 100644
index 0000000000..e10b256b03
--- /dev/null
+++ b/devtools/client/shared/classnames.js
@@ -0,0 +1,40 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+"use strict";
+
+/**
+ * Take any number of parameters and returns a space-concatenated string.
+ * If a parameter is a non-empty string, it's automatically added to the result.
+ * If a parameter is an object, for each entry, if the value is truthy, then the key
+ * is added to the result.
+ *
+ * For example: `classnames("hi", null, undefined, false, { foo: true, bar: false })` will
+ * return `"hi foo"`
+ *
+ *
+ * @param  {...string|object} argss
+ * @returns String
+ */
+module.exports = function (...args) {
+  let className = "";
+
+  for (const arg of args) {
+    if (!arg) {
+      continue;
+    }
+
+    if (typeof arg == "string") {
+      className += " " + arg;
+    } else if (Object(arg) === arg) {
+      // We don't test that we have an Object literal, so we can be as fast as we can
+      for (const key in arg) {
+        if (arg[key]) {
+          className += " " + key;
+        }
+      }
+    }
+  }
+
+  return className.trim();
+};