Fix entire db flush when no "only" keys found

lib/database_cleaner/redis/deletion.rb

@@ -3,13 +3,13 @@
 module DatabaseCleaner
   module Redis
     class Deletion < Strategy
-      def initialize only: [], except: []
+      def initialize only: nil, except: nil
         @only = only
         @except = except
       end
 
       def clean
-        if @only.none? && @except.none?
+        if @only.nil? && @except.nil?
           connection.flushdb
         else
           keys_to_delete.each do |key|
@@ -23,9 +23,8 @@ def clean
       private
 
       def keys_to_delete
-        only = expand_keys(@only)
-        except = expand_keys(@except)
-        only = connection.keys if only.none?
+        only = @only.nil? ? connection.keys : expand_keys(@only)
+        except = @except.nil? ? [] : expand_keys(@except)
         (only - except)
       end
 

spec/database_cleaner/redis/deletion_spec.rb

@@ -31,6 +31,15 @@
         expect { subject.clean }.to change { @redis.keys.size }.from(2).to(1)
         expect(@redis.get('Gadget')).to eq '1'
       end
+
+      context "but nothing matches in the database" do
+        subject { described_class.new(only: ['Foo']) }
+
+        it "does not delete the database" do
+          expect { subject.clean }.not_to change { @redis.keys.size }
+          expect(@redis.keys).to match_array(["Widget", "Gadget"])
+        end
+      end
     end
 
     context "with wildcard keys" do
@@ -40,6 +49,15 @@
         expect { subject.clean }.to change { @redis.keys.size }.from(2).to(1)
         expect(@redis.get('Gadget')).to eq '1'
       end
+
+      context "but nothing matches in the database" do
+        subject { described_class.new(only: ['Foo*']) }
+
+        it "does not delete the database" do
+          expect { subject.clean }.not_to change { @redis.keys.size }
+          expect(@redis.keys).to match_array(["Widget", "Gadget"])
+        end
+      end
     end
   end
 
@@ -63,6 +81,44 @@
     end
   end
 
+  context "with the :only and :except options" do
+    context "with concrete keys" do
+      subject { described_class.new(only: ['Widget', 'Gadget'], except: ['Gadget']) }
+
+      it "only deletes the difference between the specified keys" do
+        expect { subject.clean }.to change { @redis.keys.size }.from(2).to(1)
+        expect(@redis.get('Gadget')).to eq '1'
+      end
+
+      context "but :only does not match anything in the database" do
+        subject { described_class.new(only: ['Foo', 'Bar'], except: ['Gadget']) }
+
+        it "does not delete anything in the database" do
+          expect { subject.clean }.not_to change { @redis.keys.size }
+          expect(@redis.keys).to match_array(["Widget", "Gadget"])
+        end
+      end
+    end
+
+    context "with wildcard keys" do
+      subject { described_class.new(only: ['Widge*', 'Gadge*'], except: ['Ga*']) }
+
+      it "only deletes the difference between the specified keys" do
+        expect { subject.clean }.to change { @redis.keys.size }.from(2).to(1)
+        expect(@redis.get('Gadget')).to eq '1'
+      end
+
+      context "but :only does not match anything in the database" do
+        subject { described_class.new(only: ['F*', 'B*'], except: ['Ga*']) }
+
+        it "does not delete the database" do
+          expect { subject.clean }.not_to change { @redis.keys.size }
+          expect(@redis.keys).to match_array(["Widget", "Gadget"])
+        end
+      end
+    end
+  end
+
   context "when passing url" do
     it "still works" do
       url = @redis.connection[:id]