From a4216a3fb1a152069f3f9468f2d0b0fc3f83a305 Mon Sep 17 00:00:00 2001
From: Julian Pasquale <jpasquale@fu.do>
Date: Mon, 16 Mar 2026 16:12:54 -0300
Subject: [PATCH] Handle nil values in encode, decode, and Sequel plugin

---
 lib/pgvector.rb                |  4 ++++
 lib/sequel/plugins/pgvector.rb |  5 ++++-
 test/pgvector_test.rb          |  8 ++++++++
 test/sequel_test.rb            | 13 +++++++++++++
 4 files changed, 29 insertions(+), 1 deletion(-)

diff --git a/lib/pgvector.rb b/lib/pgvector.rb
index 0b2ca72..1e4665d 100644
--- a/lib/pgvector.rb
+++ b/lib/pgvector.rb
@@ -9,6 +9,8 @@ module Pgvector
   autoload :PG, "pgvector/pg"
 
   def self.encode(data)
+    return nil if data.nil?
+
     if data.is_a?(Vector) || data.is_a?(HalfVector) || data.is_a?(SparseVector)
       data.to_s
     else
@@ -17,6 +19,8 @@ def self.encode(data)
   end
 
   def self.decode(string)
+    return nil if string.nil?
+
     if string[0] == "["
       Vector.from_text(string).to_a
     elsif string[0] == "{"
diff --git a/lib/sequel/plugins/pgvector.rb b/lib/sequel/plugins/pgvector.rb
index 160e418..6095ca2 100644
--- a/lib/sequel/plugins/pgvector.rb
+++ b/lib/sequel/plugins/pgvector.rb
@@ -76,8 +76,11 @@ def []=(k, v)
 
         def [](k)
           if self.class.vector_columns.key?(k.to_sym)
+            value = super
+            return nil if value.nil?
+
             # to_s needed for JRuby
-            ::Pgvector.decode(super.to_s)
+            ::Pgvector.decode(value.to_s)
           else
             super
           end
diff --git a/test/pgvector_test.rb b/test/pgvector_test.rb
index 5c02c98..183ee98 100644
--- a/test/pgvector_test.rb
+++ b/test/pgvector_test.rb
@@ -24,4 +24,12 @@ def test_decode_vector
   def test_decode_sparse_vector
     assert_equal [1, 0, 2, 0, 3, 0], Pgvector.decode("{1:1.0,3:2.0,5:3.0}/6").to_a
   end
+
+  def test_encode_nil
+    assert_nil Pgvector.encode(nil)
+  end
+
+  def test_decode_nil
+    assert_nil Pgvector.decode(nil)
+  end
 end
diff --git a/test/sequel_test.rb b/test/sequel_test.rb
index e5ca02e..9853faa 100644
--- a/test/sequel_test.rb
+++ b/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_nil_embedding
+    item = Item.create(id: 4)
+    item.refresh
+    assert_nil item.embedding
+  end
+
+  def test_set_nil_embedding
+    item = Item.create(id: 4, embedding: [1, 1, 1])
+    item.update(embedding: nil)
+    item.refresh
+    assert_nil item.embedding
+  end
+
   def test_model_dataset
     create_items
     sampled_item = Item.order(Sequel.function(:random)).first