Don't render sum filter results in scientific notation.

lib/liquid/standardfilters.rb

@@ -892,9 +892,10 @@ module Liquid
         raise_property_error(property)
       end
 
-      InputIterator.new(values_for_sum, context).sum do |item|
+      result = InputIterator.new(values_for_sum, context).sum do |item|
         Utils.to_number(item)
       end
+      result.is_a?(BigDecimal) ? result.to_f : result
     end
 
     private

test/integration/standard_filter_test.rb

@@ -946,6 +946,21 @@ class StandardFiltersTest < Minitest::Test
     end
   end
 
+  def test_sum_with_floats
+    input = [0.1, 0.2, 0.3]
+    assert_equal(0.6, @filters.sum(input))
+  end
+
+  def test_sum_with_negative_float
+    input = [0.1, 0.2, -0.3]
+    assert_equal(0.0, @filters.sum(input))
+  end
+
+  def test_sum_with_float_strings
+    input = [0.1, "0.2", "0.3"]
+    assert_equal(0.6, @filters.sum(input))
+  end
+
   def test_sum_with_nested_arrays
     input = [1, [2, [3, 4]]]
 
@@ -994,6 +1009,22 @@ class StandardFiltersTest < Minitest::Test
     assert(t.foo > 0)
   end
 
+  def test_render_sum_of_floats
+    assert_equal(Liquid::Template.parse('{{ foo | sum }}').render("foo" => [0.1, 0.2, 0.3]), "0.6")
+  end
+
+  def test_render_sum_of_negative_floats
+    assert_equal(Liquid::Template.parse('{{ foo | sum }}').render("foo" => [0.1, -0.2, 0.3]), "0.2")
+  end
+
+  def test_render_sum_negative_float_result
+    assert_equal(Liquid::Template.parse('{{ foo | sum }}').render("foo" => [0.1, -0.2, -0.3]), "-0.4")
+  end
+
+  def test_render_sum_float_zero_result
+    assert_equal(Liquid::Template.parse('{{ foo | sum }}').render("foo" => [0.1, 0.2, -0.3]), "0.0")
+  end
+
   private
 
   def with_timezone(tz)