bolt/freelist_test.go

96 lines
2.7 KiB
Go

package bolt
import (
"testing"
"unsafe"
"github.com/stretchr/testify/assert"
)
// Ensure that a page is added to a transaction's freelist.
func TestFreelistFree(t *testing.T) {
f := &freelist{pending: make(map[txnid][]pgid)}
f.free(100, &page{id: 12})
assert.Equal(t, f.pending[100], []pgid{12})
}
// Ensure that a page and its overflow is added to a transaction's freelist.
func TestFreelistFreeOverflow(t *testing.T) {
f := &freelist{pending: make(map[txnid][]pgid)}
f.free(100, &page{id: 12, overflow: 3})
assert.Equal(t, f.pending[100], []pgid{12, 13, 14, 15})
}
// Ensure that a transaction's free pages can be released.
func TestFreelistRelease(t *testing.T) {
f := &freelist{pending: make(map[txnid][]pgid)}
f.free(100, &page{id: 12, overflow: 1})
f.free(100, &page{id: 9})
f.free(102, &page{id: 39})
f.release(100)
f.release(101)
assert.Equal(t, f.ids, []pgid{13, 12, 9})
f.release(102)
assert.Equal(t, f.ids, []pgid{39, 13, 12, 9})
}
// Ensure that a freelist can find contiguous blocks of pages.
func TestFreelistAllocate(t *testing.T) {
f := &freelist{ids: []pgid{18, 13, 12, 9, 7, 6, 5, 4, 3}}
assert.Equal(t, f.allocate(2), pgid(12))
assert.Equal(t, f.allocate(1), pgid(18))
assert.Equal(t, f.allocate(3), pgid(5))
assert.Equal(t, f.allocate(3), pgid(0))
assert.Equal(t, f.allocate(2), pgid(3))
assert.Equal(t, f.allocate(1), pgid(9))
assert.Equal(t, f.allocate(0), pgid(0))
assert.Equal(t, f.ids, []pgid{})
}
// Ensure that a freelist can deserialize from a freelist page.
func TestFreelistRead(t *testing.T) {
// Create a page.
var buf [4096]byte
page := (*page)(unsafe.Pointer(&buf[0]))
page.flags = freelistPageFlag
page.count = 2
// Insert 2 page ids.
ids := (*[3]pgid)(unsafe.Pointer(&page.ptr))
ids[0] = 23
ids[1] = 50
// Deserialize page into a freelist.
f := &freelist{pending: make(map[txnid][]pgid)}
f.read(page)
// Ensure that there are two page ids in the freelist.
assert.Equal(t, len(f.ids), 2)
assert.Equal(t, f.ids[0], pgid(23))
assert.Equal(t, f.ids[1], pgid(50))
}
// Ensure that a freelist can serialize into a freelist page.
func TestFreelistWrite(t *testing.T) {
// Create a freelist and write it to a page.
var buf [4096]byte
f := &freelist{ids: []pgid{12, 39}, pending: make(map[txnid][]pgid)}
f.pending[100] = []pgid{28, 11}
f.pending[101] = []pgid{3}
p := (*page)(unsafe.Pointer(&buf[0]))
f.write(p)
// Read the page back out.
f2 := &freelist{pending: make(map[txnid][]pgid)}
f2.read(p)
// Ensure that the freelist is correct.
// All pages should be present and in reverse order.
assert.Equal(t, len(f2.ids), 5)
assert.Equal(t, f2.ids[0], pgid(39))
assert.Equal(t, f2.ids[1], pgid(28))
assert.Equal(t, f2.ids[2], pgid(12))
assert.Equal(t, f2.ids[3], pgid(11))
assert.Equal(t, f2.ids[4], pgid(3))
}