From b2b2cedb06dea9deffbe1693be6be4913801788d Mon Sep 17 00:00:00 2001
From: John Cowen <johncowen@users.noreply.github.com>
Date: Tue, 23 Jun 2020 18:34:21 +0100
Subject: [PATCH] ui: Make sure right trim doesn't try to overtrim (#8171)

---
 ui-v2/app/utils/right-trim.js             |  5 ++++-
 ui-v2/tests/unit/utils/right-trim-test.js | 16 ++++++++++++++++
 2 files changed, 20 insertions(+), 1 deletion(-)

diff --git a/ui-v2/app/utils/right-trim.js b/ui-v2/app/utils/right-trim.js
index 5e1b1d3c46..35af22815c 100644
--- a/ui-v2/app/utils/right-trim.js
+++ b/ui-v2/app/utils/right-trim.js
@@ -1,4 +1,7 @@
 export default function rightTrim(str = '', search = '') {
   const pos = str.length - search.length;
-  return str.lastIndexOf(search) === pos ? str.substr(0, pos) : str;
+  if (pos >= 0) {
+    return str.lastIndexOf(search) === pos ? str.substr(0, pos) : str;
+  }
+  return str;
 }
diff --git a/ui-v2/tests/unit/utils/right-trim-test.js b/ui-v2/tests/unit/utils/right-trim-test.js
index f8efb2cf6a..6898de8e9c 100644
--- a/ui-v2/tests/unit/utils/right-trim-test.js
+++ b/ui-v2/tests/unit/utils/right-trim-test.js
@@ -37,6 +37,22 @@ module('Unit | Utility | right trim', function() {
         args: ['/a/folder/here/', '/a/folder/here/'],
         expected: '',
       },
+      {
+        args: ['/a/folder/here/', '-'],
+        expected: '/a/folder/here/',
+      },
+      {
+        args: ['/a/folder/here/', 'here'],
+        expected: '/a/folder/here/',
+      },
+      {
+        args: ['here', '/here'],
+        expected: 'here',
+      },
+      {
+        args: ['/here', '/here'],
+        expected: '',
+      },
     ].forEach(function(item) {
       const actual = rightTrim(...item.args);
       assert.equal(actual, item.expected);