dialyzer: Unfold cerl patterns containing maps

Dialyzer relies heavily on the assumption that the type of a literal
that is used as a pattern is the type of any value that can match that
pattern. For maps, that is not true, and it was causing bad analysis
results. A new help function dialyzer_utils:refold_pattern/1 identifies
maps in literal patterns, and unfolds and labels them, allowing them to
be properly analysed.

1 files changed, 0 insertions, 8 deletions

diff --git a/lib/dialyzer/test/map_SUITE_data/results/map_galore b/lib/dialyzer/test/map_SUITE_data/results/map_galore
index 08c99e0c9a..721b417bb3 100644
--- a/lib/dialyzer/test/map_SUITE_data/results/map_galore
+++ b/lib/dialyzer/test/map_SUITE_data/results/map_galore
@@ -2,9 +2,6 @@
 map_galore.erl:1000: A key of type 42 cannot exist in a map of type #{1:='a', 2:='b', 4:='d', 5:='e', float()=>'c' | 'v'}
 map_galore.erl:1080: A key of type 'nonexisting' cannot exist in a map of type #{#{'map':='key', 'one':='small'}:=[32 | 49 | 97 | 101 | 107 | 108 | 109 | 112 | 115 | 121,...], #{'map':='key', 'second':='small'}:=[32 | 50 | 97 | 101 | 107 | 108 | 109 | 112 | 115 | 121,...], #{'map':='key', 'third':='small'}:=[32 | 51 | 97 | 101 | 107 | 108 | 109 | 112 | 115 | 121,...], 10:='a0', 11:='a1', 12:='a2', 13:='a3', 14:='a4', 15:='a5', 16:='a6', 17:='a7', 18:='a8', 19:='a9', 20:='b0', 21:='b1', 22:='b2', 23:='b3', 24:='b4', 25:='b5', 26:='b6', 27:='b7', 28:='b8', 29:='b9', 30:=[48 | 99,...], 31:=[49 | 99,...], 32:=[50 | 99,...], 33:=[51 | 99,...], 34:=[52 | 99,...], 35:=[53 | 99,...], 36:=[54 | 99,...], 37:=[55 | 99,...], 38:=[56 | 99,...], 39:=[57 | 99,...], <<_:16>> | [48 | 49 | 50 | 51 | 52 | 53 | 54 | 55 | 56 | 57,...] | float() | {[[48 | 49 | 50 | 51 | 52 | 53 | 54 | 55 | 56 | 57,...],...]} | #{10:='a0', 11:='a1', 12:='a2', 13:='a3', 14:='a4', 15:='a5', 17:='a7', 18:='a8', 19:='a9', 20:='b0', 21:='b1', 22:='b2', 23:='b3', 24:='b4', 25:='b5', 27:='b7', 28:='b8', 29:='b9', 30:=[48 | 99,...], 31:=[49 | 99,...], 32:=[50 | 99,...], 33:=[51 | 99,...], 34:=[52 | 99,...], 35:=[53 | 99,...], 37:=[55 | 99,...], 38:=[56 | 99,...], 39:=[57 | 99,...], 'k16'=>'a6', 'k26'=>'b6', 'k36'=>[54 | 99,...], 16=>'a6', 26=>'b6', 36=>[54 | 99,...], <<_:16>> | [48 | 49 | 50 | 51 | 52 | 53 | 54 | 55 | 56 | 57,...] | {[[48 | 49 | 50 | 51 | 52 | 53 | 54 | 55 | 56 | 57,...],...]}=>[48 | 49 | 50 | 51 | 52 | 53 | 54 | 55 | 56 | 57 | 100 | 101,...]}=>atom() | [1..255,...]}
 map_galore.erl:1082: A key of type 42 cannot exist in a map of type #{#{'map':='key', 'one':='small'}:=[32 | 49 | 97 | 101 | 107 | 108 | 109 | 112 | 115 | 121,...], #{'map':='key', 'second':='small'}:=[32 | 50 | 97 | 101 | 107 | 108 | 109 | 112 | 115 | 121,...], #{'map':='key', 'third':='small'}:=[32 | 51 | 97 | 101 | 107 | 108 | 109 | 112 | 115 | 121,...], 10:='a0', 11:='a1', 12:='a2', 13:='a3', 14:='a4', 15:='a5', 16:='a6', 17:='a7', 18:='a8', 19:='a9', 20:='b0', 21:='b1', 22:='b2', 23:='b3', 24:='b4', 25:='b5', 26:='b6', 27:='b7', 28:='b8', 29:='b9', 30:=[48 | 99,...], 31:=[49 | 99,...], 32:=[50 | 99,...], 33:=[51 | 99,...], 34:=[52 | 99,...], 35:=[53 | 99,...], 36:=[54 | 99,...], 37:=[55 | 99,...], 38:=[56 | 99,...], 39:=[57 | 99,...], <<_:16>> | [48 | 49 | 50 | 51 | 52 | 53 | 54 | 55 | 56 | 57,...] | float() | {[[48 | 49 | 50 | 51 | 52 | 53 | 54 | 55 | 56 | 57,...],...]} | #{10:='a0', 11:='a1', 12:='a2', 13:='a3', 14:='a4', 15:='a5', 17:='a7', 18:='a8', 19:='a9', 20:='b0', 21:='b1', 22:='b2', 23:='b3', 24:='b4', 25:='b5', 27:='b7', 28:='b8', 29:='b9', 30:=[48 | 99,...], 31:=[49 | 99,...], 32:=[50 | 99,...], 33:=[51 | 99,...], 34:=[52 | 99,...], 35:=[53 | 99,...], 37:=[55 | 99,...], 38:=[56 | 99,...], 39:=[57 | 99,...], 'k16'=>'a6', 'k26'=>'b6', 'k36'=>[54 | 99,...], 16=>'a6', 26=>'b6', 36=>[54 | 99,...], <<_:16>> | [48 | 49 | 50 | 51 | 52 | 53 | 54 | 55 | 56 | 57,...] | {[[48 | 49 | 50 | 51 | 52 | 53 | 54 | 55 | 56 | 57,...],...]}=>[48 | 49 | 50 | 51 | 52 | 53 | 54 | 55 | 56 | 57 | 100 | 101,...]}=>atom() | [1..255,...]}
-map_galore.erl:1109: Function t_guard_bifs/1 has no local return
-map_galore.erl:1114: The pattern 'true' can never match the type 'false'
-map_galore.erl:1123: The pattern ~{}~ can never match the type #{'a':=1, <<_:16>>=>[104 | 105,...]}
 map_galore.erl:1140: The call map_galore:map_guard_sequence_1(#{'seq':=6, 'val':=[101,...]}) will never return since it differs in the 1st argument from the success typing arguments: (#{'seq':=1 | 2 | 3 | 4 | 5, 'val':=[97 | 98 | 99 | 100 | 101,...], #{'map':='key', 'one':='small'}=>[32 | 49 | 97 | 101 | 107 | 108 | 109 | 112 | 115 | 121,...], #{'map':='key', 'second':='small'}=>[32 | 50 | 97 | 101 | 107 | 108 | 109 | 112 | 115 | 121,...], #{'map':='key', 'third':='small'}=>[32 | 51 | 97 | 101 | 107 | 108 | 109 | 112 | 115 | 121,...], 10=>'a0', 11=>'a1', 12=>'a2', 13=>'a3', 14=>'a4', 15=>'a5', 16=>'a6', 17=>'a7', 18=>'a8', 19=>'a9', 20=>'b0', 21=>'b1', 22=>'b2', 23=>'b3', 24=>'b4', 25=>'b5', 26=>'b6', 27=>'b7', 28=>'b8', 29=>'b9', 30=>[48 | 99,...], 31=>[49 | 99,...], 32=>[50 | 99,...], 33=>[51 | 99,...], 34=>[52 | 99,...], 35=>[53 | 99,...], 36=>[54 | 99,...], 37=>[55 | 99,...], 38=>[56 | 99,...], 39=>[57 | 99,...], <<_:16>> | [48 | 49 | 50 | 51 | 52 | 53 | 54 | 55 | 56 | 57,...] | float() | {[any(),...]} | #{10:='a0', 11:='a1', 12:='a2', 13:='a3', 14:='a4', 15:='a5', 17:='a7', 18:='a8', 19:='a9', 20:='b0', 21:='b1', 22:='b2', 23:='b3', 24:='b4', 25:='b5', 27:='b7', 28:='b8', 29:='b9', 30:=[any(),...], 31:=[any(),...], 32:=[any(),...], 33:=[any(),...], 34:=[any(),...], 35:=[any(),...], 37:=[any(),...], 38:=[any(),...], 39:=[any(),...], 'k16'=>'a6', 'k26'=>'b6', 'k36'=>[any(),...], 16=>'a6', 26=>'b6', 36=>[any(),...], <<_:16>> | [any(),...] | {_}=>[any(),...]}=>atom() | [1..255,...]})
 map_galore.erl:1141: The call map_galore:map_guard_sequence_2(#{'b':=5}) will never return since it differs in the 1st argument from the success typing arguments: (#{'a':='gg' | 'kk' | 'sc' | 3 | 4, 'b'=>'other' | 3 | 4 | 5, 'c'=>'sc2', #{'map':='key', 'one':='small'}=>[32 | 49 | 97 | 101 | 107 | 108 | 109 | 112 | 115 | 121,...], #{'map':='key', 'second':='small'}=>[32 | 50 | 97 | 101 | 107 | 108 | 109 | 112 | 115 | 121,...], #{'map':='key', 'third':='small'}=>[32 | 51 | 97 | 101 | 107 | 108 | 109 | 112 | 115 | 121,...], 10=>'a0', 11=>'a1', 12=>'a2', 13=>'a3', 14=>'a4', 15=>'a5', 16=>'a6', 17=>'a7', 18=>'a8', 19=>'a9', 20=>'b0', 21=>'b1', 22=>'b2', 23=>'b3', 24=>'b4', 25=>'b5', 26=>'b6', 27=>'b7', 28=>'b8', 29=>'b9', 30=>[48 | 99,...], 31=>[49 | 99,...], 32=>[50 | 99,...], 33=>[51 | 99,...], 34=>[52 | 99,...], 35=>[53 | 99,...], 36=>[54 | 99,...], 37=>[55 | 99,...], 38=>[56 | 99,...], 39=>[57 | 99,...], <<_:16>> | [48 | 49 | 50 | 51 | 52 | 53 | 54 | 55 | 56 | 57,...] | float() | {[any(),...]} | #{10:='a0', 11:='a1', 12:='a2', 13:='a3', 14:='a4', 15:='a5', 17:='a7', 18:='a8', 19:='a9', 20:='b0', 21:='b1', 22:='b2', 23:='b3', 24:='b4', 25:='b5', 27:='b7', 28:='b8', 29:='b9', 30:=[any(),...], 31:=[any(),...], 32:=[any(),...], 33:=[any(),...], 34:=[any(),...], 35:=[any(),...], 37:=[any(),...], 38:=[any(),...], 39:=[any(),...], 'k16'=>'a6', 'k26'=>'b6', 'k36'=>[any(),...], 16=>'a6', 26=>'b6', 36=>[any(),...], <<_:16>> | [any(),...] | {_}=>[any(),...]}=>atom() | [1..255,...]})
 map_galore.erl:1209: The call map_galore:map_guard_sequence_1(#{'seq':=6, 'val':=[101,...], #{'map':='key', 'one':='small'}:=[32 | 49 | 97 | 101 | 107 | 108 | 109 | 112 | 115 | 121,...], #{'map':='key', 'second':='small'}:=[32 | 50 | 97 | 101 | 107 | 108 | 109 | 112 | 115 | 121,...], #{'map':='key', 'third':='small'}:=[32 | 51 | 97 | 101 | 107 | 108 | 109 | 112 | 115 | 121,...], 10:='a0', 11:='a1', 12:='a2', 13:='a3', 14:='a4', 15:='a5', 16:='a6', 17:='a7', 18:='a8', 19:='a9', 20:='b0', 21:='b1', 22:='b2', 23:='b3', 24:='b4', 25:='b5', 26:='b6', 27:='b7', 28:='b8', 29:='b9', 30:=[48 | 99,...], 31:=[49 | 99,...], 32:=[50 | 99,...], 33:=[51 | 99,...], 34:=[52 | 99,...], 35:=[53 | 99,...], 36:=[54 | 99,...], 37:=[55 | 99,...], 38:=[56 | 99,...], 39:=[57 | 99,...], <<_:16>> | [48 | 49 | 50 | 51 | 52 | 53 | 54 | 55 | 56 | 57,...] | float() | {[[48 | 49 | 50 | 51 | 52 | 53 | 54 | 55 | 56 | 57,...] | 3,...]} | #{10:='a0', 11:='a1', 12:='a2', 13:='a3', 14:='a4', 15:='a5', 17:='a7', 18:='a8', 19:='a9', 20:='b0', 21:='b1', 22:='b2', 23:='b3', 24:='b4', 25:='b5', 27:='b7', 28:='b8', 29:='b9', 30:=[48 | 99,...], 31:=[49 | 99,...], 32:=[50 | 99,...], 33:=[51 | 99,...], 34:=[52 | 99,...], 35:=[53 | 99,...], 37:=[55 | 99,...], 38:=[56 | 99,...], 39:=[57 | 99,...], 'k16'=>'a6', 'k26'=>'b6', 'k36'=>[54 | 99,...], 16=>'a6', 26=>'b6', 36=>[54 | 99,...], <<_:16>> | [48 | 49 | 50 | 51 | 52 | 53 | 54 | 55 | 56 | 57,...] | {[[48 | 49 | 50 | 51 | 52 | 53 | 54 | 55 | 56 | 57,...],...]}=>[48 | 49 | 50 | 51 | 52 | 53 | 54 | 55 | 56 | 57 | 100 | 101,...]}=>atom() | [1..255,...]}) will never return since it differs in the 1st argument from the success typing arguments: (#{'seq':=1 | 2 | 3 | 4 | 5, 'val':=[97 | 98 | 99 | 100 | 101,...], #{'map':='key', 'one':='small'}=>[32 | 49 | 97 | 101 | 107 | 108 | 109 | 112 | 115 | 121,...], #{'map':='key', 'second':='small'}=>[32 | 50 | 97 | 101 | 107 | 108 | 109 | 112 | 115 | 121,...], #{'map':='key', 'third':='small'}=>[32 | 51 | 97 | 101 | 107 | 108 | 109 | 112 | 115 | 121,...], 10=>'a0', 11=>'a1', 12=>'a2', 13=>'a3', 14=>'a4', 15=>'a5', 16=>'a6', 17=>'a7', 18=>'a8', 19=>'a9', 20=>'b0', 21=>'b1', 22=>'b2', 23=>'b3', 24=>'b4', 25=>'b5', 26=>'b6', 27=>'b7', 28=>'b8', 29=>'b9', 30=>[48 | 99,...], 31=>[49 | 99,...], 32=>[50 | 99,...], 33=>[51 | 99,...], 34=>[52 | 99,...], 35=>[53 | 99,...], 36=>[54 | 99,...], 37=>[55 | 99,...], 38=>[56 | 99,...], 39=>[57 | 99,...], <<_:16>> | [48 | 49 | 50 | 51 | 52 | 53 | 54 | 55 | 56 | 57,...] | float() | {[any(),...]} | #{10:='a0', 11:='a1', 12:='a2', 13:='a3', 14:='a4', 15:='a5', 17:='a7', 18:='a8', 19:='a9', 20:='b0', 21:='b1', 22:='b2', 23:='b3', 24:='b4', 25:='b5', 27:='b7', 28:='b8', 29:='b9', 30:=[any(),...], 31:=[any(),...], 32:=[any(),...], 33:=[any(),...], 34:=[any(),...], 35:=[any(),...], 37:=[any(),...], 38:=[any(),...], 39:=[any(),...], 'k16'=>'a6', 'k26'=>'b6', 'k36'=>[any(),...], 16=>'a6', 26=>'b6', 36=>[any(),...], <<_:16>> | [any(),...] | {_}=>[any(),...]}=>atom() | [1..255,...]})
@@ -27,10 +24,5 @@ map_galore.erl:2304: Cons will produce an improper list since its 2nd argument i
 map_galore.erl:2304: The call maps:from_list(nonempty_improper_list({'a','b'},{'b','a'})) will never return since it differs in the 1st argument from the success typing arguments: ([{_,_}])
 map_galore.erl:2305: The call maps:from_list('a') will never return since it differs in the 1st argument from the success typing arguments: ([{_,_}])
 map_galore.erl:2306: The call maps:from_list(42) will never return since it differs in the 1st argument from the success typing arguments: ([{_,_}])
-map_galore.erl:2735: Function t_has_map_fields/1 has no local return
-map_galore.erl:2743: The call map_galore:has_map_fields_2(#{'b':=2, 'c':=1}) will never return since it differs in the 1st argument from the success typing arguments: (#{'a':=3, 'b':=2, 'c':=1, 'x'=>42})
-map_galore.erl:2743: The pattern 'false' can never match the type 'true'
-map_galore.erl:2763: The pattern ~{}~ can never match the type #{'b':=2, 'c':=1, 'x'=>42}
-map_galore.erl:2765: Function has_map_fields_3/1 will never be called
 map_galore.erl:997: A key of type 'nonexisting' cannot exist in a map of type #{}
 map_galore.erl:998: A key of type 'nonexisting' cannot exist in a map of type #{1:='a', 2:='b', 4:='d', 5:='e', float()=>'c'}