updated for version 7.3.516
Problem: extend(o, o) may crash Vim.
Solution: Fix crash and add test. (Thinca and Hirohito Higashi)
diff --git a/src/testdir/test55.in b/src/testdir/test55.in
index 0cac348..cf85f57 100644
--- a/src/testdir/test55.in
+++ b/src/testdir/test55.in
@@ -352,6 +352,24 @@
:let dict4copy = deepcopy(dict4)
:$put =(l == lcopy)
:$put =(dict4 == dict4copy)
+:"
+:" Pass the same List to extend()
+:let l = [1, 2, 3, 4, 5]
+:call extend(l, l)
+:$put =string(l)
+:"
+:" Pass the same Dict to extend()
+:let d = { 'a': {'b': 'B'}}
+:call extend(d, d)
+:$put =string(d)
+:"
+:" Pass the same Dict to extend() with "error"
+:try
+: call extend(d, d, "error")
+:catch
+: $put =v:exception[:15] . v:exception[-1:-1]
+:endtry
+:$put =string(d)
:endfun
:"
:call Test(1, 2, [3, 4], {5: 6}) " This may take a while