patch 7.4.1271
Problem:    assert_false(v:false) reports an error. (Nikolai Pavlov)
Solution:   Recognize v:true and v:false. (Closes #625)
diff --git a/src/testdir/test_assert.vim b/src/testdir/test_assert.vim
index 22046e2..6d2f800 100644
--- a/src/testdir/test_assert.vim
+++ b/src/testdir/test_assert.vim
@@ -2,11 +2,13 @@
 
 func Test_assert_false()
   call assert_false(0)
+  call assert_false(v:false)
 endfunc
 
 func Test_assert_true()
   call assert_true(1)
   call assert_true(123)
+  call assert_true(v:true)
 endfunc
 
 func Test_assert_equal()