Merge pull request #12652 from kjellwinblad/kjell/rule_engine/fix/subbits/EMQX-11942

fix: add subbits/4 and subits/5 rule_engine functions

apps/emqx_rule_engine/src/emqx_rule_funcs.erl

@@ -96,6 +96,8 @@
     bytesize/1,
     subbits/2,
     subbits/3,
+    subbits/4,
+    subbits/5,
     subbits/6
 ]).
 
@@ -556,6 +558,16 @@ subbits(Bits, Len) when is_integer(Len), is_bitstring(Bits) ->
 subbits(Bits, Start, Len) when is_integer(Start), is_integer(Len), is_bitstring(Bits) ->
     get_subbits(Bits, Start, Len, <<"integer">>, <<"unsigned">>, <<"big">>).
 
+subbits(Bits, Start, Len, Type) when
+    is_integer(Start), is_integer(Len), is_bitstring(Bits)
+->
+    get_subbits(Bits, Start, Len, Type, <<"unsigned">>, <<"big">>).
+
+subbits(Bits, Start, Len, Type, Signedness) when
+    is_integer(Start), is_integer(Len), is_bitstring(Bits)
+->
+    get_subbits(Bits, Start, Len, Type, Signedness, <<"big">>).
+
 subbits(Bits, Start, Len, Type, Signedness, Endianness) when
     is_integer(Start), is_integer(Len), is_bitstring(Bits)
 ->

apps/emqx_rule_engine/test/emqx_rule_funcs_SUITE.erl

@@ -911,6 +911,17 @@ t_subbits2_float(_) ->
     ct:pal(";;;;~p", [R2]),
     ?assert((RL2 >= 0 andalso RL2 < 0.0001) orelse (RL2 =< 0 andalso RL2 > -0.0001)).
 
+t_subbits_4_args(_) ->
+    R = apply_func(subbits, [<<5.3:64/float>>, 1, 64, <<"float">>]),
+    RL = (5.3 - R),
+    ?assert((RL >= 0 andalso RL < 0.0001) orelse (RL =< 0 andalso RL > -0.0001)).
+
+t_subbits_5_args(_) ->
+    ?assertEqual(
+        456,
+        apply_func(subbits, [<<456:32/integer>>, 1, 32, <<"integer">>, <<"unsigned">>])
+    ).
+
 %%------------------------------------------------------------------------------
 %% Test cases for Hash funcs
 %%------------------------------------------------------------------------------

changes/ce/fix-12652.en.md

@@ -0,0 +1 @@
+The subbits functions with 4 and 5 parameters are documented but did not exist in the implementation. These functions have now been added.