From 24e36a7fd0dab0a83dc914fbde48355c21fc748f Mon Sep 17 00:00:00 2001
From: Eric Liu <ericyl.us@gmail.com>
Date: Fri, 26 Feb 2021 14:21:53 -0800
Subject: [PATCH] fix(truncate): preserve existing class names on node (#541)

---
 actions/truncate.js | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/actions/truncate.js b/actions/truncate.js
index b886728b..51fdfb9e 100644
--- a/actions/truncate.js
+++ b/actions/truncate.js
@@ -11,8 +11,14 @@
  * <h1 use:truncate={{ clamp: "front" }}>...</h1>
  */
 export function truncate(node, params = {}) {
+  const prefix = "bx--text-truncate--";
+
   function toggleClass(front = false) {
-    node.className = `bx--text-truncate--${front ? "front" : "end"}`;
+    const classes = [...node.classList]
+      .filter((name) => !name.startsWith(prefix))
+      .join(" ");
+
+    node.className = `${classes} ${prefix}${front ? "front" : "end"}`;
   }
 
   toggleClass(params.clamp === "front");