Ensure that $TMPDIR exists before running tests
Ensure that $TMPDIR exists before running tests

This is normally done by TestFileEnvironment if the `start_clear` parameter is True,
but TestPipEnvironment and FastTestPipEnvironment explicitly set it to False.

mujiansu/pip,qbdsoft/pip,wkeyword/pip,fiber-space/pip,graingert/pip,dstufft/pip,willingc/pip,ChristopherHogan/pip,erikrose/pip,benesch/pip,mujiansu/pip,ncoghlan/pip,sigmavirus24/pip,caosmo/pip,harrisonfeng/pip,Gabriel439/pip,qbdsoft/pip,supriyantomaftuh/pip,jythontools/pip,KarelJakubec/pip,James-Firth/pip,davidovich/pip,supriyantomaftuh/pip,James-Firth/pip,erikrose/pip,xavfernandez/pip,willingc/pip,esc/pip,mindw/pip,jythontools/pip,graingert/pip,jamezpolley/pip,KarelJakubec/pip,jythontools/pip,sigmavirus24/pip,caosmo/pip,pfmoore/pip,cjerdonek/pip,yati-sagade/pip,patricklaw/pip,rouge8/pip,chaoallsome/pip,squidsoup/pip,luzfcb/pip,RonnyPfannschmidt/pip,nthall/pip,pradyunsg/pip,natefoo/pip,ncoghlan/pip,rbtcollins/pip,harrisonfeng/pip,mindw/pip,zvezdan/pip,nthall/pip,pjdelport/pip,zorosteven/pip,habnabit/pip,Ivoz/pip,James-Firth/pip,nthall/pip,RonnyPfannschmidt/pip,h4ck3rm1k3/pip,zenlambda/pip,natefoo/pip,jamezpolley/pip,zorosteven/pip,pfmoore/pip,Ivoz/pip,willingc/pip,natefoo/pip,fiber-space/pip,RonnyPfannschmidt/pip,ianw/pip,rbtcollins/pip,supriyantomaftuh/pip,caosmo/pip,habnabit/pip,haridsv/pip,davidovich/pip,luzfcb/pip,chaoallsome/pip,esc/pip,pypa/pip,ncoghlan/pip,yati-sagade/pip,patricklaw/pip,haridsv/pip,msabramo/pip,alquerci/pip,sbidoul/pip,davidovich/pip,zenlambda/pip,erikrose/pip,jasonkying/pip,pypa/pip,radiosilence/pip,minrk/pip,mujiansu/pip,Gabriel439/pip,tdsmith/pip,techtonik/pip,jasonkying/pip,haridsv/pip,zvezdan/pip,harrisonfeng/pip,mindw/pip,pjdelport/pip,sbidoul/pip,jasonkying/pip,mattrobenolt/pip,graingert/pip,alquerci/pip,rbtcollins/pip,luzfcb/pip,blarghmatey/pip,cjerdonek/pip,pradyunsg/pip,Carreau/pip,zorosteven/pip,squidsoup/pip,blarghmatey/pip,sigmavirus24/pip,rouge8/pip,wkeyword/pip,h4ck3rm1k3/pip,squidsoup/pip,dstufft/pip,jmagnusson/pip,blarghmatey/pip,h4ck3rm1k3/pip,Carreau/pip,benesch/pip,tdsmith/pip,atdaemon/pip,qbdsoft/pip,chaoallsome/pip,jamezpolley/pip,alex/pip,ChristopherHogan/pip,prasaianooz/pip,xavfernandez/pip,jmagnusson/pip,mattrobenolt/pip,techtonik/pip,atdaemon/pip,jmagnusson/pip,xavfernandez/pip,KarelJakubec/pip,alex/pip,techtonik/pip,zenlambda/pip,Gabriel439/pip,minrk/pip,tdsmith/pip,esc/pip,wkeyword/pip,qwcode/pip,zvezdan/pip,alex/pip,prasaianooz/pip,ianw/pip,prasaianooz/pip,fiber-space/pip,qwcode/pip,msabramo/pip,pjdelport/pip,yati-sagade/pip,benesch/pip,atdaemon/pip,rouge8/pip,ChristopherHogan/pip,habnabit/pip,dstufft/pip