Read 1. as a float/decimal.

Fixes #23

lib/sxp/reader/basic.rb

@@ -26,7 +26,7 @@ def read_atom
       case buffer = read_literal
         when '.'      then buffer.to_sym
         when RATIONAL then Rational($1.to_i, $2.to_i)
-        when DECIMAL  then Float(buffer) # FIXME?
+        when DECIMAL  then Float(buffer.end_with?('.') ? "#{buffer}0" : buffer)
         when INTEGER  then Integer(buffer)
         else buffer.to_sym
       end

spec/reader_spec.rb

@@ -20,6 +20,25 @@
     end
   end
 
+  context "when reading numbers" do
+    {
+      "1" => Integer("1"),
+      "+1" => Integer("+1"),
+      "-1" => Integer("-1"),
+      "1." => Float("1.0"),
+      "1.1" => Float("1.1"),
+      "+1.1" => Float("1.1"),
+      "-1.1" => Float("-1.1"),
+      "1/2" => Rational(1, 2),
+      "+1/2" => Rational(1, 2),
+      "-1/2" => Rational(-1, 2),
+    }.each do |c, result|
+      it "reads #{c.inspect} as #{result.inspect}" do
+        expect(read(c)).to eql result
+      end      
+    end
+  end
+
   context "when reading lists" do
     it "reads '()' as an empty list" do
       expect(read('()')).to eq []