1 files changed, 29 insertions, 0 deletions
diff --git a/lib/hipe/test/maps_SUITE_data/maps_map_size.erl b/lib/hipe/test/maps_SUITE_data/maps_map_size.erl
new file mode 100644
index 0000000000..25c8e5d4c7
--- /dev/null
+++ b/lib/hipe/test/maps_SUITE_data/maps_map_size.erl
@@ -0,0 +1,29 @@
+-module(maps_map_size).
+-export([test/0]).
+
+test() ->
+    0 = map_size(id(#{})),
+    1 = map_size(id(#{a=>1})),
+    1 = map_size(id(#{a=>"wat"})),
+    2 = map_size(id(#{a=>1, b=>2})),
+    3 = map_size(id(#{a=>1, b=>2, b=>"3","33"=><<"n">>})),
+
+    true = map_is_size(#{a=>1}, 1),
+    true = map_is_size(#{a=>1, a=>2}, 1),
+    M = #{ "a" => 1, "b" => 2},
+    true  = map_is_size(M, 2),
+    false = map_is_size(M, 3),
+    true  = map_is_size(M#{ "a" => 2}, 2),
+    false = map_is_size(M#{ "c" => 2}, 2),
+
+    %% Error cases.
+    {'EXIT',{badarg,_}} = (catch map_size([])),
+    {'EXIT',{badarg,_}} = (catch map_size(<<1,2,3>>)),
+    {'EXIT',{badarg,_}} = (catch map_size(1)),
+    ok.
+
+map_is_size(M,N) when map_size(M) =:= N -> true;
+map_is_size(_,_) -> false.
+
+%% Use this function to avoid compile-time evaluation of an expression.
+id(I) -> I.