diff --git a/src/testdir/test_functions.vim b/src/testdir/test_functions.vim
index 2253879..a82c70b 100644
--- a/src/testdir/test_functions.vim
+++ b/src/testdir/test_functions.vim
@@ -189,6 +189,10 @@
   call assert_equal(65, str2nr('0101', 8))
   call assert_equal(-65, str2nr('-101', 8))
   call assert_equal(-65, str2nr('-0101', 8))
+  call assert_equal(65, str2nr('0o101', 8))
+  call assert_equal(65, str2nr('0O0101', 8))
+  call assert_equal(-65, str2nr('-0O101', 8))
+  call assert_equal(-65, str2nr('-0o0101', 8))
 
   call assert_equal(11259375, str2nr('abcdef', 16))
   call assert_equal(11259375, str2nr('ABCDEF', 16))
@@ -207,6 +211,7 @@
 
   call assert_equal(0, str2nr('0x10'))
   call assert_equal(0, str2nr('0b10'))
+  call assert_equal(0, str2nr('0o10'))
   call assert_equal(1, str2nr('12', 2))
   call assert_equal(1, str2nr('18', 8))
   call assert_equal(1, str2nr('1g', 16))