Relation.where with no args can be chained with not, like, and not_like

examples:

  Model.where.not field: nil
  #=> "SELECT * FROM models WHERE field IS NOT NULL

  Model.where.like name: 'Jeremy%'
  #=> "SELECT * FROM models WHERE name LIKE 'Jeremy%'

this feature was originally suggested by Jeremy Kemper https://github.com/rails/rails/pull/5950#issuecomment-5591330

Closes #5950

1 files changed, 78 insertions, 0 deletions

diff --git a/activerecord/test/cases/relation/where_chain_test.rb b/activerecord/test/cases/relation/where_chain_test.rb
new file mode 100644
index 0000000000..10b19da3fd
--- /dev/null
+++ b/activerecord/test/cases/relation/where_chain_test.rb
@@ -0,0 +1,78 @@
+require 'cases/helper'
+require 'models/post'
+require 'models/comment'
+
+module ActiveRecord
+  class WhereChainTest < ActiveRecord::TestCase
+    fixtures :posts
+
+    def test_not_eq
+      expected = Arel::Nodes::NotEqual.new(Post.arel_table[:title], 'hello')
+      relation = Post.where.not(title: 'hello')
+      assert_equal([expected], relation.where_values)
+    end
+
+    def test_not_null
+      expected = Arel::Nodes::NotEqual.new(Post.arel_table[:title], nil)
+      relation = Post.where.not(title: nil)
+      assert_equal([expected], relation.where_values)
+    end
+
+    def test_not_in
+      expected = Arel::Nodes::NotEqual.new(Post.arel_table[:title], %w[hello goodbye])
+      relation = Post.where.not(title: %w[hello goodbye])
+      assert_equal([expected], relation.where_values)
+    end
+
+    def test_association_not_eq
+      expected = Arel::Nodes::NotEqual.new(Comment.arel_table[:title], 'hello')
+      relation = Post.joins(:comments).where.not(comments: {title: 'hello'})
+      assert_equal(expected.to_sql, relation.where_values.first.to_sql)
+    end
+
+    def test_not_eq_with_preceding_where
+      relation = Post.where(title: 'hello').where.not(title: 'world')
+
+      expected = Arel::Nodes::Equality.new(Post.arel_table[:title], 'hello')
+      assert_equal(expected, relation.where_values.first)
+
+      expected = Arel::Nodes::NotEqual.new(Post.arel_table[:title], 'world')
+      assert_equal(expected, relation.where_values.last)
+    end
+
+    def test_not_eq_with_succeeding_where
+      relation = Post.where.not(title: 'hello').where(title: 'world')
+
+      expected = Arel::Nodes::NotEqual.new(Post.arel_table[:title], 'hello')
+      assert_equal(expected, relation.where_values.first)
+
+      expected = Arel::Nodes::Equality.new(Post.arel_table[:title], 'world')
+      assert_equal(expected, relation.where_values.last)
+    end
+
+    def test_like
+      expected = Arel::Nodes::Matches.new(Post.arel_table[:title], 'a%')
+      relation = Post.where.like(title: 'a%')
+      assert_equal([expected], relation.where_values)
+    end
+
+    def test_not_like
+      expected = Arel::Nodes::DoesNotMatch.new(Post.arel_table[:title], 'a%')
+      relation = Post.where.not_like(title: 'a%')
+      assert_equal([expected], relation.where_values)
+    end
+
+    def test_chaining_multiple
+      relation = Post.where.like(title: 'ruby on %').where.not(title: 'ruby on rails').where.not_like(title: '% ales')
+
+      expected = Arel::Nodes::Matches.new(Post.arel_table[:title], 'ruby on %')
+      assert_equal(expected, relation.where_values[0])
+
+      expected = Arel::Nodes::NotEqual.new(Post.arel_table[:title], 'ruby on rails')
+      assert_equal(expected, relation.where_values[1])
+
+      expected = Arel::Nodes::DoesNotMatch.new(Post.arel_table[:title], '% ales')
+      assert_equal(expected, relation.where_values[2])
+    end
+  end
+end