Fixing Kernel.Float, all specs passing.

kernel/bootstrap/string.rb

@@ -9,6 +9,8 @@ def to_f
     raise PrimitiveFailure, "String#to_f primitive failed"
   end
 
+  alias_method :convert_float, :to_f
+
   def __crypt__(other_str)
     Ruby.primitive :string_crypt
     raise PrimitiveFailure, "String#crypt primitive failed"

kernel/common/kernel.rb

@@ -3,13 +3,20 @@ module Kernel
   def Float(obj)
     raise TypeError, "can't convert nil into Float" if obj.nil?
 
-    if obj.is_a?(String)
+    if obj.is_a?(Float)
+      return obj
+    elsif obj.is_a?(String)
       if obj !~ /^\s*[+-]?((\d+_?)*\d+(\.(\d+_?)*\d+)?|\.(\d+_?)*\d+)(\s*|([eE][+-]?(\d+_?)*\d+)\s*)$/
         raise ArgumentError, "invalid value for Float(): #{obj.inspect}"
       end
+      return obj.convert_float
     end
 
-    Type.coerce_to(obj, Float, :to_f)
+    coerced_value = Type.coerce_to(obj, Float, :to_f)
+    if coerced_value.nan?
+      raise ArgumentError, "invalid value for Float(): #{coerced_value.inspect}"
+    end
+    coerced_value
   end
   module_function :Float
 

spec/tags/frozen/core/kernel/Float_tags.txt

@@ -1,7 +1 @@
 incomplete:Kernel#Float needs to be reviewed for spec completeness
-fails:Kernel.Float converts Strings to floats without calling #to_f
-fails:Kernel.Float converts String subclasses to floats without calling #to_f
-fails:Kernel.Float raises an Argument Error if to_f is called and it returns NaN
-fails:Kernel#Float converts Strings to floats without calling #to_f
-fails:Kernel#Float converts String subclasses to floats without calling #to_f
-fails:Kernel#Float raises an Argument Error if to_f is called and it returns NaN