File 4231-stdlib-Silence-unused_record-warnings-after-ms_trans.patch of Package erlang
From fbdad6ed4430636d93a2bf959745504c83f7bef2 Mon Sep 17 00:00:00 2001
From: Hans Bolinder <hasse@erlang.org>
Date: Tue, 13 Apr 2021 10:54:03 +0200
Subject: [PATCH] stdlib: Silence unused_record warnings after ms_transform
The parse transform `ms_transform' replaces records with tuples, which
can cause the Erlang code linter to emit warnings about unused
records.
To that end the warnings are suppressed by adding:
-compile({nowarn_unused_record, RecordNames}).
where RecordNames are the names of all replaced records (even if there
are already suppressions present).
---
lib/stdlib/src/ms_transform.erl | 79 ++++++++++++++++----------
lib/stdlib/test/ms_transform_SUITE.erl | 17 ++++--
2 files changed, 62 insertions(+), 34 deletions(-)
diff --git a/lib/stdlib/src/ms_transform.erl b/lib/stdlib/src/ms_transform.erl
index dd8417a75d..afa886be14 100644
--- a/lib/stdlib/src/ms_transform.erl
+++ b/lib/stdlib/src/ms_transform.erl
@@ -285,6 +285,7 @@ put_filename(Name) ->
put_records(R) ->
put(records,R),
ok.
+
get_records() ->
case get(records) of
undefined ->
@@ -292,6 +293,17 @@ get_records() ->
Else ->
Else
end.
+
+get_record(RName) ->
+ case lists:keyfind(RName, 1, get_records()) of
+ {RName, FieldList} ->
+ put(records_replaced_by_tuples,
+ [RName|get(records_replaced_by_tuples)]),
+ FieldList;
+ false ->
+ not_found
+ end.
+
cleanup_filename({Old,OldRec,OldWarnings}) ->
Ret = case erase(filename) of
undefined ->
@@ -333,11 +345,24 @@ record_field({record_field,_,{atom,_,FieldName},Def}, C) ->
record_field({typed_record_field,Field,_Type}, C) ->
record_field(Field, C).
-forms([F0|Fs0]) ->
- F1 = form(F0),
- Fs1 = forms(Fs0),
- [F1|Fs1];
-forms([]) -> [].
+forms(Forms0) ->
+ put(records_replaced_by_tuples, []),
+ try
+ Forms = [form(F) || F <- Forms0],
+ %% Add `-compile({nowarn_unused_record, RecordNames}).', where
+ %% RecordNames is the names of all records replaced by tuples,
+ %% in order to silence the code linter's warnings about unused
+ %% records.
+ case get(records_replaced_by_tuples) of
+ [] ->
+ Forms;
+ RNames ->
+ NoWarn = {nowarn_unused_record,[lists:usort(RNames)]},
+ [{attribute,erl_anno:new(0),compile,NoWarn}] ++ Forms
+ end
+ after
+ erase(records_replaced_by_tuples)
+ end.
form({attribute,_,file,{Filename,_}}=Form) ->
put_filename(Filename),
@@ -350,9 +375,11 @@ form({function,Line,Name0,Arity0,Clauses0}) ->
{function,Line,Name,Arity,Clauses};
form(AnyOther) ->
AnyOther.
+
function(Name, Arity, Clauses0) ->
Clauses1 = clauses(Clauses0),
{Name,Arity,Clauses1}.
+
clauses([C0|Cs]) ->
C1 = clause(C0,gb_sets:new()),
C2 = clauses(Cs),
@@ -529,12 +556,11 @@ tg({call, _Line, {atom, Line2, object},[]},_B) ->
{atom, Line2, '$_'};
tg({call, Line, {atom, _, is_record}=Call,[Object, {atom,Line3,RName}=R]},B) ->
MSObject = tg(Object,B),
- RDefs = get_records(),
- case lists:keysearch(RName,1,RDefs) of
- {value, {RName, FieldList}} ->
+ case get_record(RName) of
+ FieldList when is_list(FieldList) ->
RSize = length(FieldList)+1,
{tuple, Line, [Call, MSObject, R, {integer, Line3, RSize}]};
- _ ->
+ not_found ->
throw({error,Line3,{?ERR_GENBADREC+B#tgd.eb,RName}})
end;
tg({call, Line, {atom, Line2, FunName},ParaList},B) ->
@@ -593,9 +619,8 @@ tg({var,Line,VarName},B) ->
{atom, Line, AtomName}
end;
tg({record_field,Line,Object,RName,{atom,_Line1,KeyName}},B) ->
- RDefs = get_records(),
- case lists:keysearch(RName,1,RDefs) of
- {value, {RName, FieldList}} ->
+ case get_record(RName) of
+ FieldList when is_list(FieldList) ->
case lists:keysearch(KeyName,1, FieldList) of
{value, {KeyName,Position,_}} ->
NewObject = tg(Object,B),
@@ -605,12 +630,11 @@ tg({record_field,Line,Object,RName,{atom,_Line1,KeyName}},B) ->
throw({error,Line,{?ERR_GENBADFIELD+B#tgd.eb, RName,
KeyName}})
end;
- _ ->
+ not_found ->
throw({error,Line,{?ERR_GENBADREC+B#tgd.eb,RName}})
end;
tg({record,Line,RName,RFields},B) ->
- RDefs = get_records(),
KeyList0 = lists:foldl(fun({record_field,_,{atom,_,Key},Value},
L) ->
NV = tg(Value,B),
@@ -639,8 +663,8 @@ tg({record,Line,RName,RFields},B) ->
_ ->
ok
end,
- case lists:keysearch(RName,1,RDefs) of
- {value, {RName, FieldList0}} ->
+ case get_record(RName) of
+ FieldList0 when is_list(FieldList0) ->
FieldList1 = lists:foldl(
fun({FN,_,Def},Acc) ->
El = case lists:keysearch(FN,1,KeyList) of
@@ -663,14 +687,13 @@ tg({record,Line,RName,RFields},B) ->
check_undef_field(RName,Line,KeyList,FieldList0,
?ERR_GENBADFIELD+B#tgd.eb),
{tuple,Line,[{tuple,Line,[{atom,Line,RName}|FieldList1]}]};
- _ ->
+ not_found ->
throw({error,Line,{?ERR_GENBADREC+B#tgd.eb,RName}})
end;
tg({record_index,Line,RName,{atom,Line2,KeyName}},B) ->
- RDefs = get_records(),
- case lists:keysearch(RName,1,RDefs) of
- {value, {RName, FieldList}} ->
+ case get_record(RName) of
+ FieldList when is_list(FieldList) ->
case lists:keysearch(KeyName,1, FieldList) of
{value, {KeyName,Position,_}} ->
{integer, Line2, Position};
@@ -678,12 +701,11 @@ tg({record_index,Line,RName,{atom,Line2,KeyName}},B) ->
throw({error,Line2,{?ERR_GENBADFIELD+B#tgd.eb, RName,
KeyName}})
end;
- _ ->
+ not_found ->
throw({error,Line,{?ERR_GENBADREC+B#tgd.eb,RName}})
end;
tg({record,Line,{var,Line2,_VName}=AVName, RName,RFields},B) ->
- RDefs = get_records(),
MSVName = tg(AVName,B),
KeyList = lists:foldl(fun({record_field,_,{atom,_,Key},Value},
L) ->
@@ -694,8 +716,8 @@ tg({record,Line,{var,Line2,_VName}=AVName, RName,RFields},B) ->
end,
[],
RFields),
- case lists:keysearch(RName,1,RDefs) of
- {value, {RName, FieldList0}} ->
+ case get_record(RName) of
+ FieldList0 when is_list(FieldList0) ->
FieldList1 = lists:foldl(
fun({FN,Pos,_},Acc) ->
El = case lists:keysearch(FN,1,KeyList) of
@@ -716,7 +738,7 @@ tg({record,Line,{var,Line2,_VName}=AVName, RName,RFields},B) ->
check_undef_field(RName,Line,KeyList,FieldList0,
?ERR_GENBADFIELD+B#tgd.eb),
{tuple,Line,[{tuple,Line,[{atom,Line,RName}|FieldList1]}]};
- _ ->
+ not_found ->
throw({error,Line,{?ERR_GENBADREC+B#tgd.eb,RName}})
end;
@@ -761,7 +783,6 @@ toplevel_head_match(Other,B,_OB) ->
th({record,Line,RName,RFields},B,OB) ->
% youch...
- RDefs = get_records(),
{KeyList0,NewB} = lists:foldl(fun({record_field,_,{atom,_,Key},Value},
{L,B0}) ->
{NV,B1} = th(Value,B0,OB),
@@ -789,8 +810,8 @@ th({record,Line,RName,RFields},B,OB) ->
_ ->
ok
end,
- case lists:keysearch(RName,1,RDefs) of
- {value, {RName, FieldList0}} ->
+ case get_record(RName) of
+ FieldList0 when is_list(FieldList0) ->
FieldList1 = lists:foldl(
fun({FN,_,_},Acc) ->
El = case lists:keysearch(FN,1,KeyList) of
@@ -808,7 +829,7 @@ th({record,Line,RName,RFields},B,OB) ->
check_undef_field(RName,Line,KeyList,FieldList0,
?ERR_HEADBADFIELD),
{{tuple,Line,[{atom,Line,RName}|FieldList1]},NewB};
- _ ->
+ not_found ->
throw({error,Line,{?ERR_HEADBADREC,RName}})
end;
th({match,Line,_,_},_,_) ->
diff --git a/lib/stdlib/test/ms_transform_SUITE.erl b/lib/stdlib/test/ms_transform_SUITE.erl
index 6ac38b73fa..0aefda4724 100644
--- a/lib/stdlib/test/ms_transform_SUITE.erl
+++ b/lib/stdlib/test/ms_transform_SUITE.erl
@@ -45,6 +45,7 @@
-export([no_warnings/1]).
-export([eep37/1]).
-export([otp_14454/1]).
+-export([unused_record/1]).
init_per_testcase(_Func, Config) ->
Config.
@@ -61,7 +62,7 @@ all() ->
record_index, multipass, bitsyntax, binary_bifs, record_defaults,
andalso_orelse, float_1_function, action_function,
warnings, no_warnings, top_match, old_guards, autoimported,
- semicolon, eep37, otp_14454].
+ semicolon, eep37, otp_14454, unused_record].
groups() ->
[].
@@ -804,6 +805,13 @@ otp_14454(Config) when is_list(Config) ->
<<"ets:fun2ms(fun(A) -> A band ( erlang:'bsl'(-(-17), 3)) end)">>),
ok.
+%% OTP-17186.
+unused_record(Config) when is_list(Config) ->
+ setup(Config),
+ Record = <<"-record(r, {f}).\n\n">>,
+ Expr = <<"ets:fun2ms(fun(#r{}) -> e end)">>,
+ [] = compile_ww(Record, Expr),
+ ok.
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%% Helpers
@@ -864,8 +873,7 @@ compile_ww(Records,Expr) ->
file:write_file(FN,Prog),
{ok,Forms} = epp:parse_file(FN,"",""),
{ok,tmp,_Bin,Wlist} = compile:forms(Forms,[return_warnings,
- nowarn_unused_vars,
- nowarn_unused_record]),
+ nowarn_unused_vars]),
Wlist.
compile_no_ww(Expr) ->
@@ -878,8 +886,7 @@ compile_no_ww(Expr) ->
file:write_file(FN,Prog),
{ok,Forms} = epp:parse_file(FN,"",""),
{ok,tmp,_Bin,Wlist} = compile:forms(Forms,[return_warnings,
- nowarn_unused_vars,
- nowarn_unused_record]),
+ nowarn_unused_vars]),
Wlist.
do_eval(String) ->
--
2.26.2
