Function TestCursor_Last_EmptyPages

cursor_test.go:636–679

Ensure that a cursor can skip over empty pages that have been deleted.

(t *testing.T)

// Ensure that a cursor can skip over empty pages that have been deleted.
func TestCursor_Last_EmptyPages(t *testing.T) {
	db := btesting.MustCreateDB(t)

	// Create 1000 keys in the "widgets" bucket.
	if err := db.Update(func(tx *bolt.Tx) error {
		b, err := tx.CreateBucket([]byte("widgets"))
		if err != nil {
			t.Fatal(err)
		}

		for i := 0; i < 1000; i++ {
			if err := b.Put(u64tob(uint64(i)), []byte{}); err != nil {
				t.Fatal(err)
			}
		}

		return nil
	}); err != nil {
		t.Fatal(err)
	}

	// Delete last 800 elements to ensure last page is empty
	if err := db.Update(func(tx *bolt.Tx) error {
		b := tx.Bucket([]byte("widgets"))
		for i := 200; i < 1000; i++ {
			if err := b.Delete(u64tob(uint64(i))); err != nil {
				t.Fatal(err)
			}
		}

		c := b.Cursor()
		var n int
		for k, _ := c.Last(); k != nil; k, _ = c.Prev() {
			n++
		}
		if n != 200 {
			t.Fatalf("unexpected key count: %d", n)
		}

		return nil
	}); err != nil {
		t.Fatal(err)
	}
}

// Ensure that a Tx can iterate over all elements in a bucket.
func TestCursor_QuickCheck(t *testing.T) {