diff options
Diffstat (limited to 'lib/stdlib/src/erl_lint.erl')
| -rw-r--r-- | lib/stdlib/src/erl_lint.erl | 48 |
1 files changed, 38 insertions, 10 deletions
diff --git a/lib/stdlib/src/erl_lint.erl b/lib/stdlib/src/erl_lint.erl index a4833f940b..55e53cad3d 100644 --- a/lib/stdlib/src/erl_lint.erl +++ b/lib/stdlib/src/erl_lint.erl @@ -669,6 +669,9 @@ start(File, Opts) -> false, Opts)}, {redefined_builtin_type, bool_option(warn_redefined_builtin_type, nowarn_redefined_builtin_type, + true, Opts)}, + {singleton_typevar, + bool_option(warn_singleton_typevar, nowarn_singleton_typevar, true, Opts)} ], Enabled1 = [Category || {Category,true} <- Enabled0], @@ -2931,6 +2934,16 @@ check_type(Types, St) -> "_"++_ -> AccSt; _ -> add_error(Anno, {singleton_typevar, Var}, AccSt) end; + (Var, {seen_once_union, Anno}, AccSt) -> + case is_warn_enabled(singleton_typevar, AccSt) of + true -> + case atom_to_list(Var) of + "_"++_ -> AccSt; + _ -> add_warning(Anno, {singleton_typevar, Var}, AccSt) + end; + false -> + AccSt + end; (_Var, seen_multiple, AccSt) -> AccSt end, St1, SeenVars). @@ -2971,6 +2984,7 @@ check_type_2({var, A, Name}, SeenVars, St) -> NewSeenVars = case maps:find(Name, SeenVars) of {ok, {seen_once, _}} -> maps:put(Name, seen_multiple, SeenVars); + {ok, {seen_once_union, _}} -> maps:put(Name, seen_multiple, SeenVars); {ok, seen_multiple} -> SeenVars; error -> maps:put(Name, {seen_once, A}, SeenVars) end, @@ -3022,16 +3036,30 @@ check_type_2({type, _A, Tag, Args}=_F, SeenVars, St) when Tag =:= product; lists:foldl(fun(T, {AccSeenVars, AccSt}) -> check_type_1(T, AccSeenVars, AccSt) end, {SeenVars, St}, Args); -check_type_2({type, _A, union, Args}=_F, SeenVars, St) -> - lists:foldl(fun(T, {AccSeenVars, AccSt}) -> - {SeenVars0, St0} = check_type_1(T, SeenVars, AccSt), - UpdatedSeenVars = maps:merge_with(fun (_K, {seen_once, _}, {seen_once, _}=R) -> R; - (_K, {seen_once, _}, Else) -> Else; - (_K, Else, {seen_once, _}) -> Else; - (_K, Else1, _Else2) -> Else1 - end, SeenVars0, AccSeenVars), - {UpdatedSeenVars, St0} - end, {SeenVars, St}, Args); +check_type_2({type, _A, union, Args}=_F, SeenVars0, St) -> + lists:foldl(fun(T, {AccSeenVars0, AccSt}) -> + {SeenVars1, St0} = check_type_1(T, SeenVars0, AccSt), + AccSeenVars = maps:merge_with( + fun (K, {seen_once, Anno}, {seen_once, _}) -> + case SeenVars0 of + #{K := _} -> + %% Unused outside of this union. + {seen_once, Anno}; + #{} -> + {seen_once_union, Anno} + end; + (_K, {seen_once, Anno}, {seen_once_union, _}) -> + {seen_once_union, Anno}; + (_K, {seen_once_union, _}=R, {seen_once, _}) -> R; + (_K, {seen_once_union, _}=R, {seen_once_union, _}) -> R; + (_K, {seen_once_union, _}, Else) -> Else; + (_K, {seen_once, _}, Else) -> Else; + (_K, Else, {seen_once_union, _}) -> Else; + (_K, Else, {seen_once, _}) -> Else; + (_K, Else1, _Else2) -> Else1 + end, AccSeenVars0, SeenVars1), + {AccSeenVars, St0} + end, {SeenVars0, St}, Args); check_type_2({type, Anno, TypeName, Args}, SeenVars, St) -> #lint{module = Module, types=Types} = St, Arity = length(Args), |