diff options
| -rw-r--r-- | lib/stdlib/src/erl_lint.erl | 97 |
1 files changed, 63 insertions, 34 deletions
diff --git a/lib/stdlib/src/erl_lint.erl b/lib/stdlib/src/erl_lint.erl index b14102ac38..2508f96b91 100644 --- a/lib/stdlib/src/erl_lint.erl +++ b/lib/stdlib/src/erl_lint.erl @@ -1502,7 +1502,7 @@ pattern({op,_Line,'++',{string,_Li,_S},R}, Vt, Old, Bvt, St) -> pattern({match,_Line,Pat1,Pat2}, Vt, Old, Bvt, St0) -> {Lvt,Bvt1,St1} = pattern(Pat1, Vt, Old, Bvt, St0), {Rvt,Bvt2,St2} = pattern(Pat2, Vt, Old, Bvt, St1), - St3 = reject_bin_alias(Pat1, Pat2, St2), + St3 = reject_invalid_alias(Pat1, Pat2, Vt, St2), {vtmerge_pat(Lvt, Rvt),vtmerge_pat(Bvt1,Bvt2),St3}; %% Catch legal constant expressions, including unary +,-. pattern(Pat, _Vt, _Old, _Bvt, St) -> @@ -1517,56 +1517,77 @@ pattern_list(Ps, Vt, Old, Bvt0, St) -> {vtmerge_pat(Pvt, Psvt),vtmerge_pat(Bvt,Bvt1),St1} end, {[],[],St}, Ps). -%% reject_bin_alias(Pat, Expr, St) -> St' + + +%% reject_invalid_alias(Pat, Expr, Vt, St) -> St' %% Reject aliases for binary patterns at the top level. +%% Reject aliases for maps patterns at the top level. +%% The variables table (Vt) are for maps checkking. + +reject_invalid_alias_expr({bin,_,_}=P, {match,_,P0,E}, Vt, St0) -> + St = reject_invalid_alias(P, P0, Vt, St0), + reject_invalid_alias_expr(P, E, Vt, St); +reject_invalid_alias_expr({map,_,_}=P, {match,_,P0,E}, Vt, St0) -> + St = reject_invalid_alias(P, P0, Vt, St0), + reject_invalid_alias_expr(P, E, Vt, St); +reject_invalid_alias_expr({match,_,_,_}=P, {match,_,P0,E}, Vt, St0) -> + St = reject_invalid_alias(P, P0, Vt, St0), + reject_invalid_alias_expr(P, E, Vt, St); +reject_invalid_alias_expr(_, _, _, St) -> St. -reject_bin_alias_expr({bin,_,_}=P, {match,_,P0,E}, St0) -> - St = reject_bin_alias(P, P0, St0), - reject_bin_alias_expr(P, E, St); -reject_bin_alias_expr({match,_,_,_}=P, {match,_,P0,E}, St0) -> - St = reject_bin_alias(P, P0, St0), - reject_bin_alias_expr(P, E, St); -reject_bin_alias_expr(_, _, St) -> St. -%% reject_bin_alias(Pat1, Pat2, St) -> St' +%% reject_invalid_alias(Pat1, Pat2, St) -> St' %% Aliases of binary patterns, such as <<A:8>> = <<B:4,C:4>> or even %% <<A:8>> = <<A:8>>, are not allowed. Traverse the patterns in parallel %% and generate an error if any binary aliases are found. %% We generate an error even if is obvious that the overall pattern can't %% possibly match, for instance, {a,<<A:8>>,c}={x,<<A:8>>} WILL generate an %% error. +%% Maps should reject unbound variables here. -reject_bin_alias({bin,Line,_}, {bin,_,_}, St) -> +reject_invalid_alias({bin,Line,_}, {bin,_,_}, _, St) -> add_error(Line, illegal_bin_pattern, St); -reject_bin_alias({cons,_,H1,T1}, {cons,_,H2,T2}, St0) -> - St = reject_bin_alias(H1, H2, St0), - reject_bin_alias(T1, T2, St); -reject_bin_alias({tuple,_,Es1}, {tuple,_,Es2}, St) -> - reject_bin_alias_list(Es1, Es2, St); -reject_bin_alias({record,_,Name1,Pfs1}, {record,_,Name2,Pfs2}, +reject_invalid_alias({map,_Line,Ps1}, {map,_,Ps2}, Vt, St0) -> + Fun = fun ({map_field_exact,L,{var,_,K},_V}, Sti) -> + case is_var_bound(K,Vt) of + true -> + Sti; + false -> + add_error(L, {unbound_var,K}, Sti) + end; + ({map_field_exact,_L,_K,_V}, Sti) -> + Sti + end, + foldl(Fun, foldl(Fun, St0, Ps1), Ps2); +reject_invalid_alias({cons,_,H1,T1}, {cons,_,H2,T2}, Vt, St0) -> + St = reject_invalid_alias(H1, H2, Vt, St0), + reject_invalid_alias(T1, T2, Vt, St); +reject_invalid_alias({tuple,_,Es1}, {tuple,_,Es2}, Vt, St) -> + reject_invalid_alias_list(Es1, Es2, Vt, St); +reject_invalid_alias({record,_,Name1,Pfs1}, {record,_,Name2,Pfs2}, Vt, #lint{records=Recs}=St) -> case {dict:find(Name1, Recs),dict:find(Name2, Recs)} of {{ok,{_Line1,Fields1}},{ok,{_Line2,Fields2}}} -> - reject_bin_alias_rec(Pfs1, Pfs2, Fields1, Fields2, St); + reject_invalid_alias_rec(Pfs1, Pfs2, Fields1, Fields2, Vt, St); {_,_} -> %% One or more non-existing records. (An error messages has %% already been generated, so we are done here.) St end; -reject_bin_alias({match,_,P1,P2}, P, St0) -> - St = reject_bin_alias(P1, P, St0), - reject_bin_alias(P2, P, St); -reject_bin_alias(P, {match,_,_,_}=M, St) -> - reject_bin_alias(M, P, St); -reject_bin_alias(_P1, _P2, St) -> St. - -reject_bin_alias_list([E1|Es1], [E2|Es2], St0) -> - St = reject_bin_alias(E1, E2, St0), - reject_bin_alias_list(Es1, Es2, St); -reject_bin_alias_list(_, _, St) -> St. - -reject_bin_alias_rec(PfsA0, PfsB0, FieldsA0, FieldsB0, St) -> +reject_invalid_alias({match,_,P1,P2}, P, Vt, St0) -> + St = reject_invalid_alias(P1, P, Vt, St0), + reject_invalid_alias(P2, P, Vt, St); +reject_invalid_alias(P, {match,_,_,_}=M, Vt, St) -> + reject_invalid_alias(M, P, Vt, St); +reject_invalid_alias(_P1, _P2, _Vt, St) -> St. + +reject_invalid_alias_list([E1|Es1], [E2|Es2], Vt, St0) -> + St = reject_invalid_alias(E1, E2, Vt, St0), + reject_invalid_alias_list(Es1, Es2, Vt, St); +reject_invalid_alias_list(_, _, _, St) -> St. + +reject_invalid_alias_rec(PfsA0, PfsB0, FieldsA0, FieldsB0, Vt, St) -> %% We treat records as if they have been converted to tuples. PfsA1 = rbia_field_vars(PfsA0), PfsB1 = rbia_field_vars(PfsB0), @@ -1582,7 +1603,7 @@ reject_bin_alias_rec(PfsA0, PfsB0, FieldsA0, FieldsB0, St) -> D = sofs:projection({external,fun({_,_,P1,_,P2}) -> {P1,P2} end}, C), E = sofs:to_external(D), {Ps1,Ps2} = lists:unzip(E), - reject_bin_alias_list(Ps1, Ps2, St). + reject_invalid_alias_list(Ps1, Ps2, Vt, St). rbia_field_vars(Fs) -> [{Name,Pat} || {record_field,_,{atom,_,Name},Pat} <- Fs]. @@ -2284,7 +2305,7 @@ expr({'catch',Line,E}, Vt, St0) -> expr({match,_Line,P,E}, Vt, St0) -> {Evt,St1} = expr(E, Vt, St0), {Pvt,Bvt,St2} = pattern(P, vtupdate(Evt, Vt), St1), - St = reject_bin_alias_expr(P, E, St2), + St = reject_invalid_alias_expr(P, E, Vt, St2), {vtupdate(Bvt, vtmerge(Evt, Pvt)),St}; %% No comparison or boolean operators yet. expr({op,_Line,_Op,A}, Vt, St) -> @@ -2381,7 +2402,7 @@ is_valid_call(Call) -> _ -> true end. -%% is_valid_map_key(K,St) -> true | false +%% is_valid_map_key(K) -> true | false %% variables are allowed for patterns only at the top of the tree is_valid_map_key({var,_,_}) -> true; @@ -3413,6 +3434,14 @@ warn_unused_vars(U, Vt, St0) -> UVt = map(fun ({V,{State,_,Ls}}) -> {V,{State,used,Ls}} end, U), {vtmerge(Vt, UVt), St1}. + +is_var_bound(V, Vt) -> + case orddict:find(V, Vt) of + {ok,{bound,_Usage,_}} -> true; + _ -> false + end. + + %% vtupdate(UpdVarTable, VarTable) -> VarTable. %% Add the variables in the updated vartable to VarTable. The variables %% will be updated with their property in UpdVarTable. The state of |