Add some more internal tests to ht.

1 files changed, 27 insertions, 2 deletions

diff --git a/src/ht.erl b/src/ht.erl
index 5f41991..1fb4dd5 100644
--- a/src/ht.erl
+++ b/src/ht.erl
@@ -164,6 +164,32 @@ rightbranchdepth(Tree, Acc) ->
 %%%%%%%%%%%%%%%%%%%%
 %% Internal tests.
 
+basic_helpers_test_() ->
+    [test_bitcount()].
+
+test_bitcount() ->
+    L = [1, 2, 3, 255, 256, 511, 512, 32767, 32768, 65535, 65536,
+         2147483648, 4294967296, 8589934591, 8589934592, 18446744073709551616],
+    [[?_assertEqual(lists:nth(1, tv_bitcount(X)), ffs(X)) || X <- L],
+     [?_assertEqual(lists:nth(2, tv_bitcount(X)), fls(X)) || X <- L]].
+
+tv_bitcount(1) -> [0, 0];
+tv_bitcount(2) -> [1, 1];
+tv_bitcount(3) -> [1, 0];
+tv_bitcount(255) -> [7, 0];
+tv_bitcount(256) -> [8, 8];
+tv_bitcount(511) -> [8, 0];
+tv_bitcount(512) -> [9, 9];
+tv_bitcount(32767) -> [14, 0];
+tv_bitcount(32768) -> [15, 15];
+tv_bitcount(65535) -> [15, 0];
+tv_bitcount(65536) -> [16, 16];
+tv_bitcount(2147483648) -> [31, 31];
+tv_bitcount(4294967296) -> [32, 32];
+tv_bitcount(8589934591) -> [32, 0];
+tv_bitcount(8589934592) -> [33, 33];
+tv_bitcount(18446744073709551616) -> [64, 64].
+
 -define(TEST_VECTOR_TREES,
         [<<148,242,40,0,3,172,180,106,111,230,146,161,32,40,128,38,103,8,194,
            102,72,68, 126,70,108,47,8,216,208,146,178,107>>]).
@@ -217,8 +243,7 @@ mkhead_from_list_test() ->
                  mkhead(L)).
 
 append_eq_mth_test() ->
-    %% FIXME: Make larger trees once we've fixed That Bug.
-    L = lists:seq(1, 255),
+    L = [<<X:16>> || X <- lists:seq(0, 1024)],
     ?assertEqual(gethash((mkhead(L))#head.tree), mth(L)).