Fixed error with nil values for Sequel - resolves #7

Co-authored-by: Julian Pasquale <jpasquale@fu.do>

Author: ankane

CHANGELOG.md

@@ -1,3 +1,7 @@
+## 0.3.3 (unreleased)
+
+- Fixed error with `nil` values for Sequel
+
 ## 0.3.2 (2024-07-17)
 
 - Added `to_binary` method to `Vector`, `Bit`, and `SparseVector`

lib/sequel/plugins/pgvector.rb

@@ -10,6 +10,7 @@ def self.configure(model, *columns)
 
       module DatasetMethods
         def nearest_neighbors(column, value, distance:)
+          return extension(:null_dataset).nullify if value.nil?
           value = ::Pgvector.encode(value) unless value.is_a?(String)
           quoted_column = quote_identifier(column)
           distance = distance.to_s
@@ -67,19 +68,20 @@ def nearest_neighbors(column, **options)
         end
 
         def []=(k, v)
-          if self.class.vector_columns.key?(k.to_sym) && !v.is_a?(String)
+          if self.class.vector_columns.key?(k.to_sym) && !v.is_a?(String) && !v.nil?
             super(k, ::Pgvector.encode(v))
           else
             super
           end
         end
 
         def [](k)
-          if self.class.vector_columns.key?(k.to_sym)
+          v = super
+          if self.class.vector_columns.key?(k.to_sym) && !v.nil?
             # to_s needed for JRuby
-            ::Pgvector.decode(super.to_s)
+            ::Pgvector.decode(v.to_s)
           else
-            super
+            v
           end
         end
       end

test/sequel_test.rb

@@ -153,6 +153,19 @@ def test_instance_sparsevec_euclidean
     assert_equal [1, Math.sqrt(3)], results.map { |r| r[:neighbor_distance] }
   end
 
+  def test_model_nil
+    create_items
+    assert_equal 0, Item.nearest_neighbors(:embedding, nil, distance: "euclidean").first(5).count
+  end
+
+  def test_instance_nil
+    create_items
+    item = Item.create(id: 4, embedding: nil)
+    item.refresh
+    assert_nil item.embedding
+    assert_equal 0, item.nearest_neighbors(:embedding, distance: "euclidean").first(5).count
+  end
+
   def test_model_dataset
     create_items
     sampled_item = Item.order(Sequel.function(:random)).first