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// untested sections: 3
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package matchers
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import (
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	"fmt"
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	"reflect"
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	"github.com/onsi/gomega/format"
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)
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type BeSentMatcher struct {
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	Arg           any
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	channelClosed bool
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}
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func (matcher *BeSentMatcher) Match(actual any) (success bool, err error) {
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	if !isChan(actual) {
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		return false, fmt.Errorf("BeSent expects a channel.  Got:\n%s", format.Object(actual, 1))
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	}
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	channelType := reflect.TypeOf(actual)
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	channelValue := reflect.ValueOf(actual)
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	if channelType.ChanDir() == reflect.RecvDir {
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		return false, fmt.Errorf("BeSent matcher cannot be passed a receive-only channel.  Got:\n%s", format.Object(actual, 1))
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	}
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	argType := reflect.TypeOf(matcher.Arg)
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	assignable := argType.AssignableTo(channelType.Elem())
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	if !assignable {
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		return false, fmt.Errorf("Cannot pass:\n%s to the channel:\n%s\nThe types don't match.", format.Object(matcher.Arg, 1), format.Object(actual, 1))
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	}
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	argValue := reflect.ValueOf(matcher.Arg)
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	defer func() {
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		if e := recover(); e != nil {
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			success = false
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			err = fmt.Errorf("Cannot send to a closed channel")
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			matcher.channelClosed = true
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		}
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	}()
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	winnerIndex, _, _ := reflect.Select([]reflect.SelectCase{
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		{Dir: reflect.SelectSend, Chan: channelValue, Send: argValue},
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		{Dir: reflect.SelectDefault},
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	})
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	var didSend bool
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	if winnerIndex == 0 {
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		didSend = true
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	}
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	return didSend, nil
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}
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func (matcher *BeSentMatcher) FailureMessage(actual any) (message string) {
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	return format.Message(actual, "to send:", matcher.Arg)
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}
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func (matcher *BeSentMatcher) NegatedFailureMessage(actual any) (message string) {
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	return format.Message(actual, "not to send:", matcher.Arg)
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}
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func (matcher *BeSentMatcher) MatchMayChangeInTheFuture(actual any) bool {
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	if !isChan(actual) {
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		return false
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	}
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	return !matcher.channelClosed
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}
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