refactor spec using `SignalProducer.buffer`
refactor spec using `SignalProducer.buffer`

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iveCocoa,zhaoguohui/ReactiveCocoa,dachaoisme/ReactiveCocoa,bscarano/ReactiveCocoa,nickcheng/ReactiveCocoa,ikesyo/ReactiveCocoa,walkingsmarts/ReactiveCocoa,itschaitanya/ReactiveCocoa,ioshger0125/ReactiveCocoa,kevin-zqw/ReactiveCocoa,jeelun/ReactiveCocoa,jrmiddle/ReactiveCocoa,natestedman/ReactiveCocoa,tonyarnold/ReactiveCocoa,andersio/ReactiveCocoa,lixar/ReactiveCocoa,loupman/ReactiveCocoa,icepy/ReactiveCocoa,nikita-leonov/ReactiveCocoa,mtxs007/ReactiveCocoa,JackLian/ReactiveCocoa,sugar2010/ReactiveCocoa,imkerberos/ReactiveCocoa,Khan/ReactiveCocoa,leichunfeng/ReactiveCocoa,longv2go/ReactiveCocoa,huiping192/ReactiveCocoa,fhchina/ReactiveCocoa,tonyli508/ReactiveCocoa,Eveian/ReactiveCocoa,msdgwzhy6/ReactiveCocoa,terry408911/ReactiveCocoa,chao95957/ReactiveCocoa,almassapargali/ReactiveCocoa,ikesyo/ReactiveCocoa,vincentiss/ReactiveCocoa,alvinvarghese/ReactiveCocoa,dullgrass/ReactiveCocoa,zhenlove/ReactiveCocoa,bscarano/ReactiveCocoa,rpowelll/ReactiveCocoa,CQXfly/ReactiveCocoa,andersio/ReactiveCocoa,xiaobing2007/ReactiveCocoa,yaoxiaoyong/ReactiveCocoa,jeelun/ReactiveCocoa,Ray0218/ReactiveCocoa,BlessNeo/ReactiveCocoa,esttorhe/ReactiveCocoa,jaylib/ReactiveCocoa,pzw224/ReactiveCocoa,itschaitanya/ReactiveCocoa,stevielu/ReactiveCocoa,sandyway/ReactiveCocoa,zhiwen1024/ReactiveCocoa,sugar2010/ReactiveCocoa,dz1111/ReactiveCocoa,cnbin/ReactiveCocoa,longv2go/ReactiveCocoa,yizzuide/ReactiveCocoa,Ricowere/ReactiveCocoa,beni55/ReactiveCocoa,walkingsmarts/ReactiveCocoa,monkeydbobo/ReactiveCocoa,imkerberos/ReactiveCocoa,OneSmallTree/ReactiveCocoa,almassapargali/ReactiveCocoa,cnbin/ReactiveCocoa,FelixYin66/ReactiveCocoa,taylormoonxu/ReactiveCocoa,xiaoliyang/ReactiveCocoa,tzongw/ReactiveCocoa,dskatz22/ReactiveCocoa,buildo/ReactiveCocoa,rpowelll/ReactiveCocoa,DreamHill/ReactiveCocoa,zxq3220122/ReactiveCocoa,Ricowere/ReactiveCocoa,imkerberos/ReactiveCocoa,xumaolin/ReactiveCocoa,Liquidsoul/ReactiveCocoa,xiaobing2007/ReactiveCocoa,BrooksWon/ReactiveCocoa,200895045/ReactiveCocoa,dachaoisme/ReactiveCocoa,leelili/ReactiveCocoa,goodheart/ReactiveCocoa,Ethan89/ReactiveCocoa,mattpetters/ReactiveCocoa,cnbin/ReactiveCocoa,dskatz22/ReactiveCocoa,ShawnLeee/ReactiveCocoa,JohnJin007/ReactiveCocoa,zhenlove/ReactiveCocoa,paulyoung/ReactiveCocoa,yangyangluoluo/ReactiveCocoa,LHDsimon/ReactiveCocoa,monkeydbobo/ReactiveCocoa,luerhouhou/ReactiveCocoa,clg0118/ReactiveCocoa,nickcheng/ReactiveCocoa,Pingco/ReactiveCocoa,cogddo/ReactiveCocoa,brasbug/ReactiveCocoa,shuxiashusheng/ReactiveCocoa,wangqi211/ReactiveCocoa,tonyarnold/ReactiveCocoa,hbucius/ReactiveCocoa,howandhao/ReactiveCocoa,dullgrass/ReactiveCocoa,yytong/ReactiveCocoa,yonekawa/ReactiveCocoa,chieryw/ReactiveCocoa,calebd/ReactiveCocoa,zxq3220122/ReactiveCocoa,dachaoisme/ReactiveCocoa,LHDsimon/ReactiveCocoa,ztchena/ReactiveCocoa,windgo/ReactiveCocoa,Ricowere/ReactiveCocoa,hilllinux/ReactiveCocoa,kiurentu/ReactiveCocoa,liufeigit/ReactiveCocoa,ericzhou2008/ReactiveCocoa,brasbug/ReactiveCocoa,taylormoonxu/ReactiveCocoa,jrmiddle/ReactiveCocoa,PSPDFKit-labs/ReactiveCocoa,emodeqidao/ReactiveCocoa,qq644531343/ReactiveCocoa,bscarano/ReactiveCocoa,on99/ReactiveCocoa,gengjf/ReactiveCocoa,natan/ReactiveCocoa,SuPair/ReactiveCocoa,qq644531343/ReactiveCocoa,liufeigit/ReactiveCocoa,mattpetters/ReactiveCocoa,pzw224/ReactiveCocoa,leelili/ReactiveCocoa,eyu1988/ReactiveCocoa,DongDongDongDong/ReactiveCocoa,sujeking/ReactiveCocoa,stupidfive/ReactiveCocoa,victorlin/ReactiveCocoa,CQXfly/ReactiveCocoa,sujeking/ReactiveCocoa,hilllinux/ReactiveCocoa,yaoxiaoyong/ReactiveCocoa,stupidfive/ReactiveCocoa,yizzuide/ReactiveCocoa,Rupert-RR/ReactiveCocoa,zzzworm/ReactiveCocoa,BlessNeo/ReactiveCocoa,PSPDFKit-labs/ReactiveCocoa,kiurentu/ReactiveCocoa,natestedman/ReactiveCocoa,dz1111/ReactiveCocoa,gengjf/ReactiveCocoa,OnTheWay1988/ReactiveCocoa,ioshger0125/ReactiveCocoa,tiger8888/ReactiveCocoa,BlessNeo/ReactiveCocoa,howandhao/ReactiveCocoa,mxxiv/ReactiveCocoa,fhchina/ReactiveCocoa,eyu1988/ReactiveCocoa,windgo/ReactiveCocoa,Liquidsoul/ReactiveCocoa,isghe/ReactiveCocoa,AlanJN/ReactiveCocoa,jam891/ReactiveCocoa,JackLian/ReactiveCocoa,RuiAAPeres/ReactiveCocoa,ceekayel/ReactiveCocoa,yangshengchaoios/ReactiveCocoa,bensonday/ReactiveCocoa,andersio/ReactiveCocoa,yangyangluoluo/ReactiveCocoa,cstars135/ReactiveCocoa,wpstarnice/ReactiveCocoa,lixar/ReactiveCocoa,Farteen/ReactiveCocoa,smilypeda/ReactiveCocoa,luerhouhou/ReactiveCocoa,Juraldinio/ReactiveCocoa,windgo/ReactiveCocoa,hj3938/ReactiveCocoa,buildo/ReactiveCocoa,isghe/ReactiveCocoa,pzw224/ReactiveCocoa,qq644531343/ReactiveCocoa,yangshengchaoios/ReactiveCocoa,dz1111/ReactiveCocoa,alvinvarghese/ReactiveCocoa,tonyli508/ReactiveCocoa,icepy/ReactiveCocoa,smilypeda/ReactiveCocoa,GuitarPlayer-Ma/ReactiveCocoa,msdgwzhy6/ReactiveCocoa,gengjf/ReactiveCocoa,xiaoliyang/ReactiveCocoa,KuPai32G/ReactiveCocoa,beni55/ReactiveCocoa,hilllinux/ReactiveCocoa,cstars135/ReactiveCocoa,cogddo/ReactiveCocoa,clg0118/ReactiveCocoa,on99/ReactiveCocoa,yangyangluoluo/ReactiveCocoa,WEIBP/ReactiveCocoa,longv2go/ReactiveCocoa,isghe/ReactiveCocoa,j364960953/ReactiveCocoa,chao95957/ReactiveCocoa,CCOOOOLL/ReactiveCocoa,sdhzwm/ReactiveCocoa,jaylib/ReactiveCocoa,huiping192/ReactiveCocoa,FelixYin66/ReactiveCocoa,zzqiltw/ReactiveCocoa,msdgwzhy6/ReactiveCocoa,rpowelll/ReactiveCocoa,sujeking/ReactiveCocoa,nickcheng/ReactiveCocoa,zhukaixy/ReactiveCocoa,nikita-leonov/ReactiveCocoa,huiping192/ReactiveCocoa,DongDongDongDong/ReactiveCocoa,ztchena/ReactiveCocoa,ceekayel/ReactiveCocoa,j364960953/ReactiveCocoa,tornade0913/ReactiveCocoa,paulyoung/ReactiveCocoa,wangqi211/ReactiveCocoa,loupman/ReactiveCocoa,KJin99/ReactiveCocoa,valleyman86/ReactiveCocoa,jsslai/ReactiveCocoa,jaylib/ReactiveCocoa,jsslai/ReactiveCocoa,tzongw/ReactiveCocoa,zhigang1992/ReactiveCocoa,beni55/ReactiveCocoa,libiao88/ReactiveCocoa,JackLian/ReactiveCocoa,jackywpy/ReactiveCocoa,loupman/ReactiveCocoa,AndyZhaoHe/ReactiveCocoa,mattpetters/ReactiveCocoa,zhukaixy/ReactiveCocoa,llb1119/test,juliangrosshauser/ReactiveCocoa,shaohung001/ReactiveCocoa,yoichitgy/ReactiveCocoa,SanChain/ReactiveCocoa,AlanJN/ReactiveCocoa,emodeqidao/ReactiveCocoa,fanghao085/ReactiveCocoa,KuPai32G/ReactiveCocoa,tornade0913/ReactiveCocoa,j364960953/ReactiveCocoa,walkingsmarts/ReactiveCocoa,zzqiltw/ReactiveCocoa,xumaolin/ReactiveCocoa,tiger8888/ReactiveCocoa,Farteen/ReactiveCocoa,ceekayel/ReactiveCocoa