Merge pull request sunspot#334 from culturecode/empty-array-support

Added support for empty arrays in restrictions.

README.md

@@ -220,6 +220,25 @@ end
 # All examples in "positive" also work negated using `without`
 ```
 
+#### Empty Restrictions
+
+```ruby
+# Passing an empty array is equivalent to a no-op, allowing you to replace this...
+Post.search do
+  with(:category_ids, id_list) if id_list.present?
+end
+
+# ...with this
+Post.search do
+  with(:category_ids, id_list)
+end
+```
+
+
+# All examples in "positive" also work negated using `without`
+```
+
+
 #### Disjunctions and Conjunctions
 
 ```ruby

sunspot/lib/sunspot/query/restriction.rb

@@ -273,10 +273,23 @@ def to_solr_conditional
       # Results must have field with value included in given collection
       #
       class AnyOf < Base
+
+        def negated?
+          if @value.empty?
+            false
+          else
+            super
+          end
+        end
+
         private
 
         def to_solr_conditional
-          "(#{@value.map { |v| solr_value v } * ' OR '})"
+          if @value.empty?
+            "[* TO *]"
+          else
+            "(#{@value.map { |v| solr_value v } * ' OR '})"
+          end
         end
       end
 
@@ -285,10 +298,22 @@ def to_solr_conditional
       # collection (only makes sense for fields with multiple values)
       #
       class AllOf < Base
+        def negated?
+          if @value.empty?
+            false
+          else
+            super
+          end
+        end
+
         private
 
         def to_solr_conditional
-          "(#{@value.map { |v| solr_value v } * ' AND '})"
+          if @value.empty?
+            "[* TO *]"
+          else
+            "(#{@value.map { |v| solr_value v } * ' AND '})"
+          end
         end
       end
 

sunspot/spec/integration/scoped_search_spec.rb

@@ -266,6 +266,44 @@ def self.test_field_type(name, attribute, field, *values)
       end.results.should == posts[0..1]
     end
 
+    it 'should return results, ignoring any restriction in a disjunction that has been passed an empty array' do
+      posts = (1..3).map { |i| Post.new(:blog_id => i)}
+      Sunspot.index!(posts)
+      Sunspot.search(Post) do
+        with(:blog_id, [])
+      end.results.should == posts
+    end
+
+    it 'should return results, ignoring any restriction in a negative disjunction that has been passed an empty array' do
+      posts = (1..3).map { |i| Post.new(:blog_id => i)}
+      Sunspot.index!(posts)
+      Sunspot.search(Post) do
+        without(:blog_id, [])
+      end.results.should == posts
+    end 
+
+    it 'should return results, ignoring any restriction in a conjunction that has been passed an empty array' do
+      posts = (1..3).map { |i| Post.new(:blog_id => i)}
+      Sunspot.index!(posts)
+      Sunspot.search(Post) do
+        all_of do
+          with(:blog_id, 1)
+          with(:blog_id, [])
+        end
+      end.results.should == posts[0..0]
+    end
+
+    it 'should return results, ignoring any restriction in a negative conjunction that has been passed an empty array' do
+      posts = (1..3).map { |i| Post.new(:blog_id => i)}
+      Sunspot.index!(posts)
+      Sunspot.search(Post) do
+        all_of do
+          with(:blog_id, 1)
+          without(:blog_id, [])
+        end
+      end.results.should == posts[0..0]
+    end
+
     it 'should return results that match a nested conjunction in a disjunction' do
       posts = [
         Post.new(:title => 'No', :blog_id => 1),