github.com/pingcap/tiflow@v0.0.0-20240520035814-5bf52d54e205/engine/pkg/containers/slice_queue_test.go (about)

     1  // Copyright 2022 PingCAP, Inc.
     2  //
     3  // Licensed under the Apache License, Version 2.0 (the "License");
     4  // you may not use this file except in compliance with the License.
     5  // You may obtain a copy of the License at
     6  //
     7  //     http://www.apache.org/licenses/LICENSE-2.0
     8  //
     9  // Unless required by applicable law or agreed to in writing, software
    10  // distributed under the License is distributed on an "AS IS" BASIS,
    11  // See the License for the specific language governing permissions and
    12  // limitations under the License.
    13  
    14  package containers
    15  
    16  import (
    17  	"sync"
    18  	"testing"
    19  
    20  	"github.com/stretchr/testify/require"
    21  )
    22  
    23  func TestSliceQueueBasics(t *testing.T) {
    24  	q := NewSliceQueue[int]()
    25  
    26  	require.False(t, checkSignal(q.C))
    27  	require.Equal(t, 0, q.Size())
    28  	q.Push(1)
    29  	require.Equal(t, 1, q.Size())
    30  	q.Push(2)
    31  	require.Equal(t, 2, q.Size())
    32  	q.Push(3)
    33  	require.Equal(t, 3, q.Size())
    34  
    35  	val, ok := q.Peek()
    36  	require.True(t, ok)
    37  	require.Equal(t, 1, val)
    38  
    39  	require.True(t, checkSignal(q.C))
    40  	val, ok = q.Pop()
    41  	require.True(t, ok)
    42  	require.Equal(t, 1, val)
    43  
    44  	val, ok = q.Peek()
    45  	require.True(t, ok)
    46  	require.Equal(t, 2, val)
    47  
    48  	require.True(t, checkSignal(q.C))
    49  	val, ok = q.Pop()
    50  	require.True(t, ok)
    51  	require.Equal(t, 2, val)
    52  
    53  	val, ok = q.Peek()
    54  	require.True(t, ok)
    55  	require.Equal(t, 3, val)
    56  
    57  	require.True(t, checkSignal(q.C))
    58  	val, ok = q.Pop()
    59  	require.True(t, ok)
    60  	require.Equal(t, 3, val)
    61  
    62  	require.False(t, checkSignal(q.C))
    63  	_, ok = q.Pop()
    64  	require.False(t, ok)
    65  
    66  	_, ok = q.Peek()
    67  	require.False(t, ok)
    68  }
    69  
    70  func TestSliceQueueManyElements(t *testing.T) {
    71  	const numElems = 10000
    72  
    73  	q := NewSliceQueue[int]()
    74  	for i := 0; i < numElems; i++ {
    75  		q.Push(i)
    76  	}
    77  	require.Equal(t, numElems, q.Size())
    78  
    79  	for i := 0; i < numElems; i++ {
    80  		val, ok := q.Pop()
    81  		require.True(t, ok)
    82  		require.Equal(t, i, val)
    83  	}
    84  	require.Equal(t, 0, q.Size())
    85  
    86  	// Repeat the test
    87  	for i := 0; i < numElems; i++ {
    88  		q.Push(i)
    89  	}
    90  	require.Equal(t, numElems, q.Size())
    91  
    92  	for i := 0; i < numElems; i++ {
    93  		val, ok := q.Pop()
    94  		require.True(t, ok)
    95  		require.Equal(t, i, val)
    96  	}
    97  	require.Equal(t, 0, q.Size())
    98  }
    99  
   100  func TestSliceQueueConcurrentWriteAndRead(t *testing.T) {
   101  	const numElems = 1000000
   102  
   103  	q := NewSliceQueue[int]()
   104  	var wg sync.WaitGroup
   105  	wg.Add(1)
   106  	go func() {
   107  		defer wg.Done()
   108  
   109  		for i := 0; i < numElems; i++ {
   110  			q.Push(i)
   111  		}
   112  	}()
   113  
   114  	wg.Add(1)
   115  	go func() {
   116  		defer wg.Done()
   117  
   118  		counter := 0
   119  		for {
   120  			<-q.C
   121  
   122  			for {
   123  				val, ok := q.Pop()
   124  				if !ok {
   125  					break
   126  				}
   127  				require.Equal(t, counter, val)
   128  				counter++
   129  				if counter == numElems {
   130  					return
   131  				}
   132  			}
   133  		}
   134  	}()
   135  
   136  	wg.Wait()
   137  	require.Equal(t, 0, q.Size())
   138  }
   139  
   140  func checkSignal(ch <-chan struct{}) bool {
   141  	select {
   142  	case <-ch:
   143  		return true
   144  	default:
   145  		return false
   146  	}
   147  }