FloatFilter to support empty_is_nil option

lib/mutations/float_filter.rb

@@ -1,9 +1,10 @@
 module Mutations
   class FloatFilter < AdditionalFilter
     @default_options = {
-      :nils => false,       # true allows an explicit nil to be valid. Overrides any other options
-      :min => nil,          # lowest value, inclusive
-      :max => nil           # highest value, inclusive
+      :nils => false,          # true allows an explicit nil to be valid. Overrides any other options,
+      :empty_is_nil => false,  # if true, treat empty string as if it were nil
+      :min => nil,             # lowest value, inclusive
+      :max => nil              # highest value, inclusive
     }
 
     def filter(data)
@@ -15,7 +16,13 @@ def filter(data)
       end
 
       # Now check if it's empty:
-      return [data, :empty] if data == ""
+      if data == ""
+        if options[:empty_is_nil]
+          return [nil, (:nils unless options[:nils])]
+        else
+          return [data, :empty]
+        end
+      end
 
       # Ensure it's the correct data type (Float)
       if !data.is_a?(Float)

spec/float_filter_spec.rb

@@ -72,6 +72,19 @@
     assert_equal :empty, errors
   end
 
+  it "considers empty strings to be nil if empty_is_nil option is used" do
+    f = Mutations::FloatFilter.new(:empty_is_nil => true)
+    _filtered, errors = f.filter("")
+    assert_equal :nils, errors
+  end
+
+  it "returns empty strings as nil if empty_is_nil option is used" do
+    f = Mutations::FloatFilter.new(:empty_is_nil => true, :nils => true)
+    filtered, errors = f.filter("")
+    assert_equal nil, filtered
+    assert_equal nil, errors
+  end
+
   it "considers low numbers invalid" do
     f = Mutations::FloatFilter.new(:min => 10)
     filtered, errors = f.filter(3)