l13Tests :: TestTree
l13Tests = decisionTestGroup "l17" "If-Modified-Since exists?"
  [ testCase "True ==> l14" $
      let rq = req { reqHeaders = HashMap.singleton hIfModifiedSince [dateStr] }
      in after' l13 resource rq @?= Decision' "l14"
  , testCase "False ==> m16" $
      after' l13 resource req @?= Decision' "m16"
  ]
l13Tests :: TestTree
l13Tests = decisionTestGroup "l17" "If-Modified-Since exists?"
  [ testCase "True ==> l14" $
      let rq = req { reqHeaders = HashMap.singleton hIfModifiedSince [dateStr] }
      in after' l13 resource rq @?= Decision' "l14"
  , testCase "False ==> m16" $
      after' l13 resource req @?= Decision' "m16"
  ]
l13Tests = decisionTestGroup "l17" "If-Modified-Since exists?"
  [ testCase "True ==> l14" $
      let rq = req { reqHeaders = HashMap.singleton hIfModifiedSince [dateStr] }
      in after' l13 resource rq @?= Decision' "l14"
  , testCase "False ==> m16" $
      after' l13 resource req @?= Decision' "m16"
  ]