Tighten up double regexp.

* Allows `.1`
* Disallows `+INF`, and `InF`.
* Disallows `NAN`

All are parsed, but considered invalid.

Author: gkellogg

lib/rdf/model/literal/double.rb

@@ -12,7 +12,7 @@ module RDF; class Literal
   # @since 0.2.1
   class Double < Numeric
     DATATYPE = RDF::XSD.double
-    GRAMMAR  = /^(?:NaN|(?:[\+\-]?(?:INF|(?:\d+(\.\d*)?(e[\+\-]?\d+)?))))$/i.freeze
+    GRAMMAR  = /^(?:NaN|\-?INF|[+\-]?(?:\d+(:?\.\d*)?|\.\d+)(?:[eE][\+\-]?\d+)?)$/.freeze
 
     ##
     # @param  [String, Float, #to_f] value
@@ -21,11 +21,11 @@ def initialize(value, datatype: nil, lexical: nil, **options)
       @datatype = RDF::URI(datatype || self.class.const_get(:DATATYPE))
       @string   = lexical || (value if value.is_a?(String))
       @object   = case
-        when value.is_a?(::String) then case value
+        when value.is_a?(::String) then case value.upcase
           when '+INF'  then 1/0.0
           when 'INF'  then 1/0.0
           when '-INF' then -1/0.0
-          when 'NaN'  then 0/0.0
+          when 'NAN'  then 0/0.0
           else Float(value.sub(/\.[eE]/, '.0E')) rescue nil
         end
         when value.is_a?(::Float)     then value

spec/model_literal_spec.rb

@@ -487,7 +487,10 @@ def self.literals(*selector)
       %w(+INF      INF),
       %w(INF       INF),
       %w(-INF      -INF),
+      %w(+INF      INF),
       #%w(NaN       NaN),
+      #%w(NAN        NaN),
+      %w(InF        INF),
       %w(3E1       3.0E1)
     ]
     it_behaves_like 'RDF::Literal validation', RDF::XSD.double,
@@ -500,12 +503,9 @@ def self.literals(*selector)
         1.0e+1
         1.0e-10
         123.456e4
-        +INF
         INF
         -INF
-        Inf
         NaN
-        NAN
         3E1
       ),
       %w(foo 12.xyz 1.0ez) + ['1.1e1 foo', 'foo 1.1e1']