From 0145578493a123ee0ff0e9adc4921582d456d366 Mon Sep 17 00:00:00 2001
From: mrazauskas <72159681+mrazauskas@users.noreply.github.com>
Date: Fri, 13 Aug 2021 14:22:16 +0300
Subject: [PATCH] chore(utils): improve `stripWhitespace` utility (#9668)

---
 packages/utils/src/lang.js       |  3 ++-
 packages/utils/test/lang.test.js | 10 +++++-----
 2 files changed, 7 insertions(+), 6 deletions(-)

diff --git a/packages/utils/src/lang.js b/packages/utils/src/lang.js
index e0cdd6275f..79c5d20e80 100644
--- a/packages/utils/src/lang.js
+++ b/packages/utils/src/lang.js
@@ -29,7 +29,8 @@ const WHITESPACE_REPLACEMENTS = [
   [/{\n{2,}/g, '{\n'], // strip start padding from blocks
   [/\n{2,}([ \t\f\r]*})/g, '\n$1'], // strip end padding from blocks
   [/\n{3,}/g, '\n\n'], // strip multiple blank lines (1 allowed)
-  [/\n{2,}$/g, '\n'] // strip blank lines EOF (0 allowed)
+  [/^\n+/, ''], // strip blank lines at the beginning of a string
+  [/\n{2,}$/, '\n'] // strip blank lines at the end of a string
 ]
 
 export const stripWhitespace = function stripWhitespace (string) {
diff --git a/packages/utils/test/lang.test.js b/packages/utils/test/lang.test.js
index 1f39ca530d..eb83324cf0 100644
--- a/packages/utils/test/lang.test.js
+++ b/packages/utils/test/lang.test.js
@@ -36,12 +36,12 @@ describe('util: lang', () => {
   })
 
   test('should strip white spaces in given argument', () => {
-    expect(stripWhitespace('foo')).toEqual('foo')
-    expect(stripWhitespace('foo\t\r\f\n')).toEqual('foo\n')
-    expect(stripWhitespace('foo{\n\n\n')).toEqual('foo{\n')
-    expect(stripWhitespace('\n\n\n\f\r\f}')).toEqual('\n\f\r\f}')
+    expect(stripWhitespace('foo\t\r \f\nbar')).toEqual('foo\nbar')
+    expect(stripWhitespace('foo{\n\n\nbar')).toEqual('foo{\nbar')
+    expect(stripWhitespace('foo\n\n\n\t \r\f}')).toEqual('foo\n\t \r\f}')
     expect(stripWhitespace('foo\n\n\nbar')).toEqual('foo\n\nbar')
-    expect(stripWhitespace('foo\n\n\n')).toEqual('foo\n')
+    expect(stripWhitespace('\n\nfoo\n')).toEqual('foo\n')
+    expect(stripWhitespace('foo\n\n')).toEqual('foo\n')
   })
 
   test('should encode html', () => {