Merge pull request #20737 from gouravtiwari/multibyte_chars_slice_fix

Fixed multibyte-chars slice! behavior to return nil for out-of-bound
parameters

1 files changed, 6 insertions, 2 deletions

diff --git a/activesupport/lib/active_support/multibyte/chars.rb b/activesupport/lib/active_support/multibyte/chars.rb
index f6a2e7e949..707cf200b5 100644
--- a/activesupport/lib/active_support/multibyte/chars.rb
+++ b/activesupport/lib/active_support/multibyte/chars.rb
@@ -86,7 +86,8 @@ module ActiveSupport #:nodoc:
       end
 
       # Works like <tt>String#slice!</tt>, but returns an instance of
-      # Chars, or nil if the string was not modified.
+      # Chars, or nil if the string was not modified. The string will not be
+      # modified if the range given is out of bounds
       #
       #   string = 'Welcome'
       #   string.mb_chars.slice!(3)    # => #<ActiveSupport::Multibyte::Chars:0x000000038109b8 @wrapped_string="c">
@@ -94,7 +95,10 @@ module ActiveSupport #:nodoc:
       #   string.mb_chars.slice!(0..3) # => #<ActiveSupport::Multibyte::Chars:0x00000002eb80a0 @wrapped_string="Welo">
       #   string # => 'me'
       def slice!(*args)
-        chars(@wrapped_string.slice!(*args))
+        string_sliced = @wrapped_string.slice!(*args)
+        if string_sliced
+          chars(string_sliced)
+        end
       end
 
       # Reverses all characters in the string.