github.com/klaytn/klaytn@v1.12.1/event/subscription_test.go (about)

     1  // Modifications Copyright 2018 The klaytn Authors
     2  // Copyright 2016 The go-ethereum Authors
     3  // This file is part of the go-ethereum library.
     4  //
     5  // The go-ethereum library is free software: you can redistribute it and/or modify
     6  // it under the terms of the GNU Lesser General Public License as published by
     7  // the Free Software Foundation, either version 3 of the License, or
     8  // (at your option) any later version.
     9  //
    10  // The go-ethereum library is distributed in the hope that it will be useful,
    11  // but WITHOUT ANY WARRANTY; without even the implied warranty of
    12  // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
    13  // GNU Lesser General Public License for more details.
    14  //
    15  // You should have received a copy of the GNU Lesser General Public License
    16  // along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
    17  //
    18  // This file is derived from event/subscription_test.go (2018/06/04).
    19  // Modified and improved for the klaytn development.
    20  
    21  package event
    22  
    23  import (
    24  	"context"
    25  	"errors"
    26  	"testing"
    27  	"time"
    28  )
    29  
    30  var errInts = errors.New("error in subscribeInts")
    31  
    32  func subscribeInts(max, fail int, c chan<- int) Subscription {
    33  	return NewSubscription(func(quit <-chan struct{}) error {
    34  		for i := 0; i < max; i++ {
    35  			if i >= fail {
    36  				return errInts
    37  			}
    38  			select {
    39  			case c <- i:
    40  			case <-quit:
    41  				return nil
    42  			}
    43  		}
    44  		return nil
    45  	})
    46  }
    47  
    48  func TestNewSubscriptionError(t *testing.T) {
    49  	t.Parallel()
    50  
    51  	channel := make(chan int)
    52  	sub := subscribeInts(10, 2, channel)
    53  loop:
    54  	for want := 0; want < 10; want++ {
    55  		select {
    56  		case got := <-channel:
    57  			if got != want {
    58  				t.Fatalf("wrong int %d, want %d", got, want)
    59  			}
    60  		case err := <-sub.Err():
    61  			if err != errInts {
    62  				t.Fatalf("wrong error: got %q, want %q", err, errInts)
    63  			}
    64  			if want != 2 {
    65  				t.Fatalf("got errInts at int %d, should be received at 2", want)
    66  			}
    67  			break loop
    68  		}
    69  	}
    70  	sub.Unsubscribe()
    71  
    72  	err, ok := <-sub.Err()
    73  	if err != nil {
    74  		t.Fatal("got non-nil error after Unsubscribe")
    75  	}
    76  	if ok {
    77  		t.Fatal("channel still open after Unsubscribe")
    78  	}
    79  }
    80  
    81  func TestResubscribe(t *testing.T) {
    82  	t.Parallel()
    83  
    84  	var i int
    85  	nfails := 6
    86  	sub := Resubscribe(100*time.Millisecond, func(ctx context.Context) (Subscription, error) {
    87  		// fmt.Printf("call #%d @ %v\n", i, time.Now())
    88  		i++
    89  		if i == 2 {
    90  			// Delay the second failure a bit to reset the resubscribe interval.
    91  			time.Sleep(200 * time.Millisecond)
    92  		}
    93  		if i < nfails {
    94  			return nil, errors.New("oops")
    95  		}
    96  		sub := NewSubscription(func(unsubscribed <-chan struct{}) error { return nil })
    97  		return sub, nil
    98  	})
    99  
   100  	<-sub.Err()
   101  	if i != nfails {
   102  		t.Fatalf("resubscribe function called %d times, want %d times", i, nfails)
   103  	}
   104  }
   105  
   106  func TestResubscribeAbort(t *testing.T) {
   107  	t.Parallel()
   108  
   109  	done := make(chan error)
   110  	sub := Resubscribe(0, func(ctx context.Context) (Subscription, error) {
   111  		select {
   112  		case <-ctx.Done():
   113  			done <- nil
   114  		case <-time.After(2 * time.Second):
   115  			done <- errors.New("context given to resubscribe function not canceled within 2s")
   116  		}
   117  		return nil, nil
   118  	})
   119  
   120  	sub.Unsubscribe()
   121  	if err := <-done; err != nil {
   122  		t.Fatal(err)
   123  	}
   124  }