From 985f5a1fae38caed84cde8bc09f6f60e91710f20 Mon Sep 17 00:00:00 2001
From: Hans Bolinder <hasse@erlang.org>
Date: Wed, 15 Nov 2017 12:57:57 +0100
Subject: dialyzer: Extend the map implementation's handling of ?unit
The Maps implementation handles ?unit in more cases.
Exactly when t_is_none_or_unit() is to be called is not clear to me.
The added cases are about a map type being ?unit, but the key or the
value of an association can also be ?unit, but that is not always
checked.
---
lib/dialyzer/src/dialyzer_typesig.erl | 12 +++++++-----
lib/dialyzer/test/map_SUITE_data/results/map_anon_fun | 2 ++
lib/dialyzer/test/map_SUITE_data/src/map_anon_fun.erl | 9 +++++++++
3 files changed, 18 insertions(+), 5 deletions(-)
create mode 100644 lib/dialyzer/test/map_SUITE_data/results/map_anon_fun
create mode 100644 lib/dialyzer/test/map_SUITE_data/src/map_anon_fun.erl
(limited to 'lib/dialyzer')
diff --git a/lib/dialyzer/src/dialyzer_typesig.erl b/lib/dialyzer/src/dialyzer_typesig.erl
index c4d8f45447..d03326ec97 100644
--- a/lib/dialyzer/src/dialyzer_typesig.erl
+++ b/lib/dialyzer/src/dialyzer_typesig.erl
@@ -41,7 +41,7 @@
t_is_float/1, t_is_fun/1,
t_is_integer/1, t_non_neg_integer/0,
t_is_list/1, t_is_nil/1, t_is_none/1, t_is_number/1,
- t_is_singleton/1,
+ t_is_singleton/1, t_is_none_or_unit/1,
t_limit/2, t_list/0, t_list/1,
t_list_elements/1, t_nonempty_list/1, t_maybe_improper_list/0,
@@ -528,13 +528,14 @@ traverse(Tree, DefinedVars, State) ->
false -> t_any();
true ->
MT = t_inf(lookup_type(MapVar, Map), t_map()),
- case t_is_none(MT) of
+ case t_is_none_or_unit(MT) of
true -> t_none();
false ->
DisjointFromKeyType =
fun(ShadowKey) ->
- t_is_none(t_inf(lookup_type(ShadowKey, Map),
- KeyType))
+ ST = t_inf(lookup_type(ShadowKey, Map),
+ KeyType),
+ t_is_none_or_unit(ST)
end,
case lists:all(DisjointFromKeyType, ShadowKeys) of
true -> t_map_get(KeyType, MT);
@@ -567,7 +568,8 @@ traverse(Tree, DefinedVars, State) ->
case cerl:is_literal(OpTree) andalso
cerl:concrete(OpTree) =:= exact of
true ->
- case t_is_none(t_inf(ShadowedKeys, KeyType)) of
+ ST = t_inf(ShadowedKeys, KeyType),
+ case t_is_none_or_unit(ST) of
true ->
t_map_put({KeyType, t_any()}, AccType);
false ->
diff --git a/lib/dialyzer/test/map_SUITE_data/results/map_anon_fun b/lib/dialyzer/test/map_SUITE_data/results/map_anon_fun
new file mode 100644
index 0000000000..cfca5b1407
--- /dev/null
+++ b/lib/dialyzer/test/map_SUITE_data/results/map_anon_fun
@@ -0,0 +1,2 @@
+
+map_anon_fun.erl:4: Function g/1 will never be called
diff --git a/lib/dialyzer/test/map_SUITE_data/src/map_anon_fun.erl b/lib/dialyzer/test/map_SUITE_data/src/map_anon_fun.erl
new file mode 100644
index 0000000000..e77016d68a
--- /dev/null
+++ b/lib/dialyzer/test/map_SUITE_data/src/map_anon_fun.erl
@@ -0,0 +1,9 @@
+-module(map_anon_fun).
+
+%% Not exported.
+g(A) ->
+ maps:map(fun F(K, {V, _C}) ->
+ F(K, V);
+ F(_K, _V) ->
+ #{ system => {A} }
+ end, #{}).
--
cgit v1.2.3