patch 7.4.1164
Problem:    No tests for comparing special variables.  Error in jsondecode()
            not reported.  test_json does not work Japanse system.
Solution:   Set scriptencoding. (Ken Takata) Add a few more tests. Add error.
diff --git a/src/testdir/test_viml.vim b/src/testdir/test_viml.vim
index f1a7cb4..645f1b5 100644
--- a/src/testdir/test_viml.vim
+++ b/src/testdir/test_viml.vim
@@ -946,6 +946,18 @@
     call assert_equal('true', '' . v:true)
     call assert_equal('none', '' . v:none)
     call assert_equal('null', '' . v:null)
+
+    call assert_true(v:false == 0)
+    call assert_false(v:false != 0)
+    call assert_true(v:true == 1)
+    call assert_false(v:true != 1)
+    call assert_false(v:true == v:false)
+    call assert_true(v:true != v:false)
+
+    call assert_true(v:null == 0)
+    call assert_false(v:null != 0)
+    call assert_true(v:none == 0)
+    call assert_false(v:none != 0)
 endfunc
 
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