Add Horse tests and optimize cow_date:rfc2109/1

Makefile

@@ -5,6 +5,10 @@ CT_SUITES = eunit
 
 include erlang.mk
 
+.PHONY: gen perfs
+
+# Mimetypes module generator.
+
 GEN_URL = http://svn.apache.org/repos/asf/httpd/httpd/trunk/docs/conf/mime.types
 GEN_SRC = src/cow_mimetypes.erl.src
 GEN_OUT = src/cow_mimetypes.erl
@@ -25,3 +29,15 @@ gen:
 	$(gen_verbose) cat $(GEN_SRC) \
 		| tail -n +`grep -n "%% GENERATED" $(GEN_SRC) | cut -d : -f 1` \
 		>> $(GEN_OUT)
+
+# Performance testing.
+
+deps/horse:
+	git clone -n -- https://github.com/extend/horse $(DEPS_DIR)/horse
+	cd $(DEPS_DIR)/horse ; git checkout -q master
+	$(MAKE) -C $(DEPS_DIR)/horse
+
+perfs: ERLC_OPTS += -DPERF=1 +'{parse_transform, horse_autoexport}'
+perfs: clean deps deps/horse app
+	$(gen_verbose) erl -noshell -pa ebin deps/horse/ebin \
+		-eval 'horse:app_perf($(PROJECT)), init:stop().'

src/cow_date.erl

@@ -21,10 +21,13 @@
 -spec rfc2109(calendar:datetime()) -> binary().
 rfc2109({Date = {Y, Mo, D}, {H, Mi, S}}) ->
 	Wday = calendar:day_of_the_week(Date),
-	<< (weekday(Wday))/binary, ", ", (pad_int(D))/binary, "-",
-		(month(Mo))/binary, "-", (list_to_binary(integer_to_list(Y)))/binary,
-		" ", (pad_int(H))/binary, $:, (pad_int(Mi))/binary,
-		$:, (pad_int(S))/binary, " GMT" >>.
+	<<	(weekday(Wday))/binary, ", ",
+		(pad_int(D))/binary, "-",
+		(month(Mo))/binary, "-",
+		(year(Y))/binary, " ",
+		(pad_int(H))/binary, ":",
+		(pad_int(Mi))/binary, ":",
+		(pad_int(S))/binary, " GMT" >>.
 
 -ifdef(TEST).
 rfc2109_test_() ->
@@ -35,13 +38,86 @@ rfc2109_test_() ->
 	[{R, fun() -> R = rfc2109(D) end} || {R, D} <- Tests].
 -endif.
 
+-ifdef(PERF).
+horse_rfc2019_20130101_000000() ->
+	horse:repeat(100000,
+		rfc2109({{2013, 1, 1}, {0, 0, 0}})
+	).
+
+horse_rfc2019_20131231_235959() ->
+	horse:repeat(100000,
+		rfc2109({{2013, 12, 31}, {23, 59, 59}})
+	).
+
+horse_rfc2019_12340506_070809() ->
+	horse:repeat(100000,
+		rfc2109({{1234, 5, 6}, {7, 8, 9}})
+	).
+-endif.
+
 %% Internal.
 
--spec pad_int(0..59) -> binary().
-pad_int(X) when X < 10 ->
-	<< $0, ($0 + X) >>;
-pad_int(X) ->
-	list_to_binary(integer_to_list(X)).
+-spec pad_int(0..59) -> <<_:16>>.
+pad_int( 0) -> <<"00">>;
+pad_int( 1) -> <<"01">>;
+pad_int( 2) -> <<"02">>;
+pad_int( 3) -> <<"03">>;
+pad_int( 4) -> <<"04">>;
+pad_int( 5) -> <<"05">>;
+pad_int( 6) -> <<"06">>;
+pad_int( 7) -> <<"07">>;
+pad_int( 8) -> <<"08">>;
+pad_int( 9) -> <<"09">>;
+pad_int(10) -> <<"10">>;
+pad_int(11) -> <<"11">>;
+pad_int(12) -> <<"12">>;
+pad_int(13) -> <<"13">>;
+pad_int(14) -> <<"14">>;
+pad_int(15) -> <<"15">>;
+pad_int(16) -> <<"16">>;
+pad_int(17) -> <<"17">>;
+pad_int(18) -> <<"18">>;
+pad_int(19) -> <<"19">>;
+pad_int(20) -> <<"20">>;
+pad_int(21) -> <<"21">>;
+pad_int(22) -> <<"22">>;
+pad_int(23) -> <<"23">>;
+pad_int(24) -> <<"24">>;
+pad_int(25) -> <<"25">>;
+pad_int(26) -> <<"26">>;
+pad_int(27) -> <<"27">>;
+pad_int(28) -> <<"28">>;
+pad_int(29) -> <<"29">>;
+pad_int(30) -> <<"30">>;
+pad_int(31) -> <<"31">>;
+pad_int(32) -> <<"32">>;
+pad_int(33) -> <<"33">>;
+pad_int(34) -> <<"34">>;
+pad_int(35) -> <<"35">>;
+pad_int(36) -> <<"36">>;
+pad_int(37) -> <<"37">>;
+pad_int(38) -> <<"38">>;
+pad_int(39) -> <<"39">>;
+pad_int(40) -> <<"40">>;
+pad_int(41) -> <<"41">>;
+pad_int(42) -> <<"42">>;
+pad_int(43) -> <<"43">>;
+pad_int(44) -> <<"44">>;
+pad_int(45) -> <<"45">>;
+pad_int(46) -> <<"46">>;
+pad_int(47) -> <<"47">>;
+pad_int(48) -> <<"48">>;
+pad_int(49) -> <<"49">>;
+pad_int(50) -> <<"50">>;
+pad_int(51) -> <<"51">>;
+pad_int(52) -> <<"52">>;
+pad_int(53) -> <<"53">>;
+pad_int(54) -> <<"54">>;
+pad_int(55) -> <<"55">>;
+pad_int(56) -> <<"56">>;
+pad_int(57) -> <<"57">>;
+pad_int(58) -> <<"58">>;
+pad_int(59) -> <<"59">>.
 
 -spec weekday(1..7) -> <<_:24>>.
 weekday(1) -> <<"Mon">>;
@@ -65,3 +141,66 @@ month( 9) -> <<"Sep">>;
 month(10) -> <<"Oct">>;
 month(11) -> <<"Nov">>;
 month(12) -> <<"Dec">>.
+
+-spec year(pos_integer()) -> <<_:32>>.
+year(1970) -> <<"1970">>;
+year(1971) -> <<"1971">>;
+year(1972) -> <<"1972">>;
+year(1973) -> <<"1973">>;
+year(1974) -> <<"1974">>;
+year(1975) -> <<"1975">>;
+year(1976) -> <<"1976">>;
+year(1977) -> <<"1977">>;
+year(1978) -> <<"1978">>;
+year(1979) -> <<"1979">>;
+year(1980) -> <<"1980">>;
+year(1981) -> <<"1981">>;
+year(1982) -> <<"1982">>;
+year(1983) -> <<"1983">>;
+year(1984) -> <<"1984">>;
+year(1985) -> <<"1985">>;
+year(1986) -> <<"1986">>;
+year(1987) -> <<"1987">>;
+year(1988) -> <<"1988">>;
+year(1989) -> <<"1989">>;
+year(1990) -> <<"1990">>;
+year(1991) -> <<"1991">>;
+year(1992) -> <<"1992">>;
+year(1993) -> <<"1993">>;
+year(1994) -> <<"1994">>;
+year(1995) -> <<"1995">>;
+year(1996) -> <<"1996">>;
+year(1997) -> <<"1997">>;
+year(1998) -> <<"1998">>;
+year(1999) -> <<"1999">>;
+year(2000) -> <<"2000">>;
+year(2001) -> <<"2001">>;
+year(2002) -> <<"2002">>;
+year(2003) -> <<"2003">>;
+year(2004) -> <<"2004">>;
+year(2005) -> <<"2005">>;
+year(2006) -> <<"2006">>;
+year(2007) -> <<"2007">>;
+year(2008) -> <<"2008">>;
+year(2009) -> <<"2009">>;
+year(2010) -> <<"2010">>;
+year(2011) -> <<"2011">>;
+year(2012) -> <<"2012">>;
+year(2013) -> <<"2013">>;
+year(2014) -> <<"2014">>;
+year(2015) -> <<"2015">>;
+year(2016) -> <<"2016">>;
+year(2017) -> <<"2017">>;
+year(2018) -> <<"2018">>;
+year(2019) -> <<"2019">>;
+year(2020) -> <<"2020">>;
+year(2021) -> <<"2021">>;
+year(2022) -> <<"2022">>;
+year(2023) -> <<"2023">>;
+year(2024) -> <<"2024">>;
+year(2025) -> <<"2025">>;
+year(2026) -> <<"2026">>;
+year(2027) -> <<"2027">>;
+year(2028) -> <<"2028">>;
+year(2029) -> <<"2029">>;
+year(Year) -> list_to_binary(integer_to_list(Year)).