lbcd/blockchain/mediantime_test.go
Dave Collins b69a849114 Import btcchain repo into blockchain directory.
This commit contains the entire btcchain repository along with several
changes needed to move all of the files into the blockchain directory in
order to prepare it for merging.  This does NOT update btcd or any of the
other packages to use the new location as that will be done separately.

- All import paths in the old btcchain test files have been changed to
  the new location
- All references to btcchain as the package name have been changed to
  blockchain
2015-01-30 15:49:59 -06:00

106 lines
3.9 KiB
Go

// Copyright (c) 2013-2014 Conformal Systems LLC.
// Use of this source code is governed by an ISC
// license that can be found in the LICENSE file.
package blockchain_test
import (
"strconv"
"testing"
"time"
"github.com/btcsuite/btcd/blockchain"
)
// TestMedianTime tests the medianTime implementation.
func TestMedianTime(t *testing.T) {
tests := []struct {
in []int64
wantOffset int64
useDupID bool
}{
// Not enough samples must result in an offset of 0.
{in: []int64{1}, wantOffset: 0},
{in: []int64{1, 2}, wantOffset: 0},
{in: []int64{1, 2, 3}, wantOffset: 0},
{in: []int64{1, 2, 3, 4}, wantOffset: 0},
// Various number of entries. The expected offset is only
// updated on odd number of elements.
{in: []int64{-13, 57, -4, -23, -12}, wantOffset: -12},
{in: []int64{55, -13, 61, -52, 39, 55}, wantOffset: 39},
{in: []int64{-62, -58, -30, -62, 51, -30, 15}, wantOffset: -30},
{in: []int64{29, -47, 39, 54, 42, 41, 8, -33}, wantOffset: 39},
{in: []int64{37, 54, 9, -21, -56, -36, 5, -11, -39}, wantOffset: -11},
{in: []int64{57, -28, 25, -39, 9, 63, -16, 19, -60, 25}, wantOffset: 9},
{in: []int64{-5, -4, -3, -2, -1}, wantOffset: -3, useDupID: true},
// The offset stops being updated once the max number of entries
// has been reached. This is actually a bug from Bitcoin Core,
// but since the time is ultimately used as a part of the
// consensus rules, it must be mirrored.
{in: []int64{-67, 67, -50, 24, 63, 17, 58, -14, 5, -32, -52}, wantOffset: 17},
{in: []int64{-67, 67, -50, 24, 63, 17, 58, -14, 5, -32, -52, 45}, wantOffset: 17},
{in: []int64{-67, 67, -50, 24, 63, 17, 58, -14, 5, -32, -52, 45, 4}, wantOffset: 17},
// Offsets that are too far away from the local time should
// be ignored.
{in: []int64{-4201, 4202, -4203, 4204, -4205}, wantOffset: 0},
// Excerise the condition where the median offset is greater
// than the max allowed adjustment, but there is at least one
// sample that is close enough to the current time to avoid
// triggering a warning about an invalid local clock.
{in: []int64{4201, 4202, 4203, 4204, -299}, wantOffset: 0},
}
// Modify the max number of allowed median time entries for these tests.
blockchain.TstSetMaxMedianTimeEntries(10)
defer blockchain.TstSetMaxMedianTimeEntries(200)
for i, test := range tests {
filter := blockchain.NewMedianTime()
for j, offset := range test.in {
id := strconv.Itoa(j)
now := time.Unix(time.Now().Unix(), 0)
tOffset := now.Add(time.Duration(offset) * time.Second)
filter.AddTimeSample(id, tOffset)
// Ensure the duplicate IDs are ignored.
if test.useDupID {
// Modify the offsets to ensure the final median
// would be different if the duplicate is added.
tOffset = tOffset.Add(time.Duration(offset) *
time.Second)
filter.AddTimeSample(id, tOffset)
}
}
// Since it is possible that the time.Now call in AddTimeSample
// and the time.Now calls here in the tests will be off by one
// second, allow a fudge factor to compensate.
gotOffset := filter.Offset()
wantOffset := time.Duration(test.wantOffset) * time.Second
wantOffset2 := time.Duration(test.wantOffset-1) * time.Second
if gotOffset != wantOffset && gotOffset != wantOffset2 {
t.Errorf("Offset #%d: unexpected offset -- got %v, "+
"want %v or %v", i, gotOffset, wantOffset,
wantOffset2)
continue
}
// Since it is possible that the time.Now call in AdjustedTime
// and the time.Now call here in the tests will be off by one
// second, allow a fudge factor to compensate.
adjustedTime := filter.AdjustedTime()
now := time.Unix(time.Now().Unix(), 0)
wantTime := now.Add(filter.Offset())
wantTime2 := now.Add(filter.Offset() - time.Second)
if !adjustedTime.Equal(wantTime) && !adjustedTime.Equal(wantTime2) {
t.Errorf("AdjustedTime #%d: unexpected result -- got %v, "+
"want %v or %v", i, adjustedTime, wantTime,
wantTime2)
continue
}
}
}