Created
December 11, 2014 19:31
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Check if a Go Channel is open or closed
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// An intersting pattern for testing, but you can use the check anywhere | |
import "testing" | |
func TestCheckingChannel(t *testing.T) { | |
stop := make(chan bool) | |
// Testing some fucntion that SHOULD close the channel | |
func (stop chan bool) { | |
close(chan) | |
}(stop) | |
// Make sure that the function does close the channel | |
_, ok := (<-stop) | |
// If we can recieve on the channel then it is NOT closed | |
if ok { | |
t.Error("Channel is not closed") | |
} | |
} |
The error will never occur. If the channel isn't closed the function will block forever on line 13.
It would work if you replaced line 13 with the following:
ok := true select { case _, ok = <-stop: default: }A
select
with adefault
clause is a non-blocking read from the channel.
Thanks , you save my day.
❤️
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@noamnelke I have never heard about overload in Go. the
close
func in this gist is just aCloser
implementationso sad