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Viewing changes to src/github.com/juju/utils/cache/cache_test.go

  • Committer: Nicholas Skaggs
  • Date: 2016-09-30 14:39:30 UTC
  • mfrom: (1.8.1)
  • Revision ID: nicholas.skaggs@canonical.com-20160930143930-vwwhrefh6ftckccy
import upstream

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src/github.com/juju/utils/cache/cache_test.go
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        c.Assert(total, gc.Equals, N)
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}
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func (*suite) TestSingleFlight(c *gc.C) {
 
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        p := cache.New(time.Minute)
 
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        start := make(chan struct{})
 
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        var wg sync.WaitGroup
 
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        wg.Add(1)
 
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        go func() {
 
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                defer wg.Done()
 
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                x, err := p.Get("x", func() (interface{}, error) {
 
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                        start <- struct{}{}
 
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                        <-start
 
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                        return 99, nil
 
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                })
 
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                c.Check(x, gc.Equals, 99)
 
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                c.Check(err, gc.Equals, nil)
 
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        }()
 
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        // Wait for the fetch to start.
 
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        <-start
 
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        wg.Add(1)
 
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        go func() {
 
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                defer wg.Done()
 
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                x, err := p.Get("x", func() (interface{}, error) {
 
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                        c.Errorf("fetch function unexpectedly called with inflight request")
 
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                        return 55, nil
 
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                })
 
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                c.Check(x, gc.Equals, 99)
 
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                c.Check(err, gc.Equals, nil)
 
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        }()
 
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        // Check that we can still get other values while the
 
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        // other fetches are in progress.
 
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        y, err := p.Get("y", func() (interface{}, error) {
 
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                return 88, nil
 
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        })
 
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        c.Check(y, gc.Equals, 88)
 
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        c.Check(err, gc.Equals, nil)
 
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        // Let the original fetch proceed, which should let the other one
 
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        // succeed too, but sleep for a little bit to let the second goroutine
 
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        // actually initiate its request.
 
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        time.Sleep(time.Millisecond)
 
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        start <- struct{}{}
 
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        wg.Wait()
 
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}
 
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var errUnexpectedFetch = errgo.New("fetch called unexpectedly")
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func fetchError(err error) func() (interface{}, error) {