feature: Add smismember

Signed-off-by: Valentin Kiselev <mrexox@evilmartians.com>

lib/mock_redis/set_methods.rb

@@ -64,6 +64,12 @@ def sismember(key, member)
       with_set_at(key) { |s| s.include?(member.to_s) }
     end
 
+    def smismember(key, *members)
+      with_set_at(key) do |set|
+        members.flatten.map { |m| set.include?(m.to_s) }
+      end
+    end
+
     def smembers(key)
       with_set_at(key, &:to_a).map(&:dup).reverse
     end

spec/commands/smismember_spec.rb

@@ -0,0 +1,34 @@
+require 'spec_helper'
+
+describe '#sismember(key, *members)' do
+  before do
+    @key = 'mock-redis-test:smismember'
+    @redises.sadd(@key, 'whiskey')
+    @redises.sadd(@key, 'beer')
+  end
+
+  it 'returns true if member is in set' do
+    @redises.smismember(@key, 'whiskey').should == [true]
+    @redises.smismember(@key, 'beer').should == [true]
+    @redises.smismember(@key, 'whiskey', 'beer').should == [true, true]
+    @redises.smismember(@key, ['whiskey', 'beer']).should == [true, true]
+  end
+
+  it 'returns false if member is not in set' do
+    @redises.smismember(@key, 'cola').should == [false]
+    @redises.smismember(@key, 'whiskey', 'cola').should == [true, false]
+    @redises.smismember(@key, ['whiskey', 'beer', 'cola']).should == [true, true, false]
+  end
+
+  it 'stringifies member' do
+    @redises.sadd(@key, '1')
+    @redises.smismember(@key, 1).should == [true]
+    @redises.smismember(@key, [1]).should == [true]
+  end
+
+  it 'treats a nonexistent value as an empty set' do
+    @redises.smismember('mock-redis-test:nonesuch', 'beer').should == [false]
+  end
+
+  it_should_behave_like 'a set-only command'
+end