Kind of fun to re-read this old thread - especially since somewhere in the last year I solved the issue (and I don’t really know when). I thought my dialyzer-fu was quite reasonable now but then this issue cropped up today (after a couple of weeks work so I can’t trace when it appeared).
Help very much appreciated!
Dialyzer Error:
lib/cldr/backend/cldr.ex:52:call
The function call will not succeed.
Cldr.Locale.put_gettext_locale_name(
%Cldr.LanguageTag{
:canonical_locale_name => <<101, 110, 45, 76, 97, 116, 110, 45, 85, 83>>,
:cldr_locale_name => <<101, 110>>,
:extensions => %{},
:gettext_locale_name => nil,
:language => <<101, 110>>,
:language_subtags => [],
:language_variant => nil,
:locale => %{},
:private_use => [],
:rbnf_locale_name => <<101, 110>>,
:requested_locale_name => <<101, 110>>,
:script => <<76, 97, 116, 110>>,
:territory => :US,
:transform => %{}
},
MyApp.Cldr
)
will never return since it differs in arguments with
positions 1st from the success typing arguments:
(
%Cldr.LanguageTag{
:canonical_locale_name => binary(),
:cldr_locale_name => nil | binary(),
:extensions => map(),
:gettext_locale_name => nil | binary(),
:language => binary(),
:language_subtags => [binary()],
:language_variant => nil | binary(),
:locale => map(),
:private_use => [binary()],
:rbnf_locale_name => nil | binary(),
:requested_locale_name => binary(),
:script => nil | binary(),
:territory => nil,
:transform => map()
},
atom()
)
Observations
The only difference between the function call and the success typing is:
# Call
:script => <<76, 97, 116, 110>>,
:territory => :US,
:transform => %{}
# Success type
:script => nil | binary(),
:territory => nil,
:transform => map()
In which the types for :territory would seem to mismatch. However if I look into my types:
# This is the type for Cldr.LanguageTag
@type territory :: atom()
@type t :: %__MODULE__{
language: String.t(),
language_subtags: [String.t()] | [],
script: String.t() | nil,
territory: Cldr.territory(),
language_variant: String.t() | nil,
locale: Cldr.LanguageTag.U.t(),
transform: map(),
extensions: map(),
private_use: [String.t()] | [],
requested_locale_name: String.t(),
canonical_locale_name: String.t(),
cldr_locale_name: String.t() | nil,
rbnf_locale_name: String.t() | nil,
gettext_locale_name: String.t() | nil
}
So I’m perplexed why the success type for :territory is nil not atom(). The called site is:
@spec put_gettext_locale_name(Cldr.LanguageTag.t(), Cldr.backend()) :: Cldr.LanguageTag.t()
def put_gettext_locale_name(%LanguageTag{} = language_tag, backend) do
gettext_locale_name = gettext_locale_name(language_tag, backend)
%{language_tag | gettext_locale_name: gettext_locale_name}
end
Which doesn’t obviously disturb the success type I would have thought?
Any and all suggestions welcome!
