ticker_test.go

Documentation: github.com/cenkalti/backoff/v4

     1  package backoff
     2  
     3  import (
     4  	"context"
     5  	"errors"
     6  	"fmt"
     7  	"log"
     8  	"testing"
     9  )
    10  
    11  func TestTicker(t *testing.T) {
    12  	const successOn = 3
    13  	var i = 0
    14  
    15  	// This function is successful on "successOn" calls.
    16  	f := func() error {
    17  		i++
    18  		log.Printf("function is called %d. time\n", i)
    19  
    20  		if i == successOn {
    21  			log.Println("OK")
    22  			return nil
    23  		}
    24  
    25  		log.Println("error")
    26  		return errors.New("error")
    27  	}
    28  
    29  	b := NewExponentialBackOff()
    30  	ticker := NewTickerWithTimer(b, &testTimer{})
    31  
    32  	var err error
    33  	for range ticker.C {
    34  		if err = f(); err != nil {
    35  			t.Log(err)
    36  			continue
    37  		}
    38  
    39  		break
    40  	}
    41  	if err != nil {
    42  		t.Errorf("unexpected error: %s", err.Error())
    43  	}
    44  	if i != successOn {
    45  		t.Errorf("invalid number of retries: %d", i)
    46  	}
    47  }
    48  
    49  func TestTickerContext(t *testing.T) {
    50  	var i = 0
    51  
    52  	ctx, cancel := context.WithCancel(context.Background())
    53  
    54  	// Cancel context as soon as it is created.
    55  	// Ticker must stop after first tick.
    56  	cancel()
    57  
    58  	// This function cancels context on "cancelOn" calls.
    59  	f := func() error {
    60  		i++
    61  		log.Printf("function is called %d. time\n", i)
    62  		log.Println("error")
    63  		return fmt.Errorf("error (%d)", i)
    64  	}
    65  
    66  	b := WithContext(NewConstantBackOff(0), ctx)
    67  	ticker := NewTickerWithTimer(b, &testTimer{})
    68  
    69  	var err error
    70  	for range ticker.C {
    71  		if err = f(); err != nil {
    72  			t.Log(err)
    73  			continue
    74  		}
    75  
    76  		ticker.Stop()
    77  		break
    78  	}
    79  	// Ticker is guaranteed to tick at least once.
    80  	if err == nil {
    81  		t.Errorf("error is unexpectedly nil")
    82  	}
    83  	if err.Error() != "error (1)" {
    84  		t.Errorf("unexpected error: %s", err)
    85  	}
    86  	if i != 1 {
    87  		t.Errorf("invalid number of retries: %d", i)
    88  	}
    89  }
    90  
    91  func TestTickerDefaultTimer(t *testing.T) {
    92  	b := NewExponentialBackOff()
    93  	ticker := NewTickerWithTimer(b, nil)
    94  	// ensure a timer was actually assigned, instead of remaining as nil.
    95  	<-ticker.C
    96  }
    97
View as plain text