base64_SUITE: Speed up roundtrip/1

Refactor roundtrip/1 into 4 test cases that can be run in parallel.
Assuming that there are 4 cores available, the group of 4 test
cases will run at roughly one fourth of the time for the original
test case.

2 files changed, 29 insertions, 63 deletions

diff --git a/lib/stdlib/test/base64_SUITE.erl b/lib/stdlib/test/base64_SUITE.erl
index cca9b967d5..75eebba6c6 100644
--- a/lib/stdlib/test/base64_SUITE.erl
+++ b/lib/stdlib/test/base64_SUITE.erl
@@ -30,7 +30,8 @@
 %% Test cases must be exported.
 -export([base64_encode/1, base64_decode/1, base64_otp_5635/1,
 	 base64_otp_6279/1, big/1, illegal/1, mime_decode/1,
-	 mime_decode_to_string/1, roundtrip/1]).
+	 mime_decode_to_string/1,
+	 roundtrip_1/1, roundtrip_2/1, roundtrip_3/1, roundtrip_4/1]).
 
 init_per_testcase(_, Config) ->
     Dog = test_server:timetrap(?t:minutes(4)),
@@ -50,10 +51,11 @@ suite() -> [{ct_hooks,[ts_install_cth]}].
 all() -> 
     [base64_encode, base64_decode, base64_otp_5635,
      base64_otp_6279, big, illegal, mime_decode, mime_decode_to_string,
-     roundtrip].
+     {group, roundtrip}].
 
 groups() -> 
-    [].
+    [{roundtrip, [parallel],
+      [roundtrip_1, roundtrip_2, roundtrip_3, roundtrip_4]}].
 
 init_per_suite(Config) ->
     Config.
@@ -242,21 +244,33 @@ mime_decode_to_string(Config) when is_list(Config) ->
 
 %%-------------------------------------------------------------------------
 
-roundtrip(Config) when is_list(Config) ->
-    Sizes = lists:seq(1, 255) ++ lists:seq(2400-5, 2440),
-    roundtrip_1(Sizes, []).
+roundtrip_1(Config) when is_list(Config) ->
+    do_roundtrip(1).
 
-roundtrip_1([NextSize|Sizes], Current) ->
+roundtrip_2(Config) when is_list(Config) ->
+    do_roundtrip(2).
+
+roundtrip_3(Config) when is_list(Config) ->
+    do_roundtrip(3).
+
+roundtrip_4(Config) when is_list(Config) ->
+    do_roundtrip(4).
+
+do_roundtrip(Offset) ->
+    Sizes = lists:seq(Offset, 255, 4) ++ lists:seq(2400-6+Offset, 2440, 4),
+    do_roundtrip_1(Sizes, []).
+
+do_roundtrip_1([NextSize|Sizes], Current) ->
     Len = length(Current),
     io:format("~p", [Len]),
-    do_roundtrip(Current),
+    do_roundtrip_2(Current),
     Next = random_byte_list(NextSize - Len, Current),
-    roundtrip_1(Sizes, Next);
-roundtrip_1([], Last) ->
+    do_roundtrip_1(Sizes, Next);
+do_roundtrip_1([], Last) ->
     io:format("~p", [length(Last)]),
-    do_roundtrip(Last).
+    do_roundtrip_2(Last).
 
-do_roundtrip(List) ->
+do_roundtrip_2(List) ->
     Bin = list_to_binary(List),
     Base64Bin = base64:encode(List),
     Base64Bin = base64:encode(Bin),
diff --git a/lib/stdlib/test/lists_SUITE.erl b/lib/stdlib/test/lists_SUITE.erl
index 5a447d58a4..a0f7fd2744 100644
--- a/lib/stdlib/test/lists_SUITE.erl
+++ b/lib/stdlib/test/lists_SUITE.erl
@@ -62,8 +62,7 @@
 	 zip_unzip/1, zip_unzip3/1, zipwith/1, zipwith3/1,
 	 filter_partition/1, 
 	 otp_5939/1, otp_6023/1, otp_6606/1, otp_7230/1,
-	 prefix/1, suffix/1, subtract/1, droplast/1, hof/1,
-	 split/1, concat/1]).
+	 suffix/1, subtract/1, droplast/1, hof/1]).
 
 %% Sort randomized lists until stopped.
 %%
@@ -124,8 +123,8 @@ groups() ->
      {tickets, [parallel], [otp_5939, otp_6023, otp_6606, otp_7230]},
      {zip, [parallel], [zip_unzip, zip_unzip3, zipwith, zipwith3]},
      {misc, [parallel], [reverse, member, dropwhile, takewhile,
-			 filter_partition, prefix, suffix, subtract,
-			 hof, split, concat]}
+			 filter_partition, suffix, subtract,
+			 hof]}
     ].
 
 init_per_suite(Config) ->
@@ -2630,19 +2629,6 @@ otp_6606(Config) when is_list(Config) ->
     ?line L2 = lists:sort(L2),
     ok.
 
-%% Test lists:prefix/2.
-prefix(Config) when is_list(Config) ->
-    true = lists:prefix([], []),
-    true = lists:prefix([], lists:seq(1, 10)),
-    true = lists:prefix([a], [a,b]),
-    true = lists:prefix(lists:seq(1, 10), lists:seq(1, 100)),
-
-    false = lists:prefix([a], []),
-    false = lists:prefix([a], [b]),
-    false = lists:prefix([a], [b,a]),
-
-    ok.
-
 %% Test lists:suffix/2.
 suffix(Config) when is_list(Config) ->
     ?line true = lists:suffix([], []),
@@ -2760,37 +2746,3 @@ hof(Config) when is_list(Config) ->
     false = lists:all(fun(N) -> N rem 2 =:= 0 end, L),
 
     ok.
-
-%% Test lists:split/2
-split(Config) when is_list(Config) ->
-    Lens = lists:seq(0, 32),
-    do_split(Lens),
-
-    %% Error cases.
-    {'EXIT',_} = (catch lists:split(a, [])),
-    {'EXIT',_} = (catch lists:split(-1, [])),
-    {'EXIT',_} = (catch lists:split(0, {a,b})),
-    ok.
-
-do_split([Len|Lens]) ->
-    List = [rand:uniform(1000) || _ <- lists:seq(1, Len)],
-    do_split_1(0, Len, List),
-    do_split(Lens);
-do_split([]) ->
-    ok.
-
-do_split_1(N, Len, List)  when N =:= Len + 1 ->
-    {'EXIT',_} = (catch lists:split(N, List));
-do_split_1(N, Len, List) ->
-    {A,B} = lists:split(N, List),
-    List = A ++ B,
-    N = length(A),
-    LenB = length(B),
-    LenB = Len - N,
-    do_split_1(N+1, Len, List).
-
-%% Test lists:concat/1 mainly for coverage.
-concat(Config) when is_list(Config) ->
-    S = integer_to_list(42) ++ "pi: " ++ float_to_list(math:pi()),
-    S = lists:concat([42,pi,": ",math:pi()]),
-    ok.