lru_test.gno

 1package lru
 2
 3import (
 4	"strconv"
 5	"testing"
 6
 7	"gno.land/p/nt/testutils/v0"
 8	"gno.land/p/nt/uassert/v0"
 9)
10
11func reset(cur realm) {
12	Reset(cross(cur))
13}
14
15func TestPutGetAndRecency(cur realm, t *testing.T) {
16	testing.SetRealm(testing.NewUserRealm(testutils.TestAddress("alice")))
17	reset(cur)
18
19	Put(cross(cur), "a", "1")
20	Put(cross(cur), "b", "2")
21
22	v, ok := Get(cross(cur), "a")
23	uassert.True(t, ok, "a should be present")
24	uassert.Equal(t, "1", v)
25
26	// miss
27	_, ok = Get(cross(cur), "zzz")
28	uassert.False(t, ok, "zzz should be absent")
29
30	// after Get("a"), a is MRU -> head
31	uassert.Equal(t, "a", c.head.key)
32	uassert.Equal(t, "b", c.tail.key)
33
34	// stats: 1 hit, 1 miss
35	uassert.Equal(t, 1, c.hits)
36	uassert.Equal(t, 1, c.miss)
37
38	// update existing key
39	Put(cross(cur), "b", "22")
40	v, _ = peek("b")
41	uassert.Equal(t, "22", v)
42	uassert.Equal(t, "b", c.head.key) // update marks MRU
43	uassert.Equal(t, 2, c.size)
44}
45
46func TestEviction(cur realm, t *testing.T) {
47	testing.SetRealm(testing.NewUserRealm(testutils.TestAddress("bob")))
48	reset(cur)
49
50	// fill beyond capacity (8): insert k0..k9
51	for i := 0; i < 10; i++ {
52		Put(cross(cur), "k"+strconv.Itoa(i), strconv.Itoa(i))
53	}
54
55	uassert.Equal(t, capacity, c.size)
56
57	// k0 and k1 should have been evicted (oldest inserts, never touched)
58	_, ok := peek("k0")
59	uassert.False(t, ok, "k0 should be evicted")
60	_, ok = peek("k1")
61	uassert.False(t, ok, "k1 should be evicted")
62
63	// newest is MRU head, k2 is now the LRU tail
64	uassert.Equal(t, "k9", c.head.key)
65	uassert.Equal(t, "k2", c.tail.key)
66
67	// touching k2 protects it; next insert evicts k3 instead
68	_, ok = Get(cross(cur), "k2")
69	uassert.True(t, ok, "k2 present")
70	Put(cross(cur), "k10", "10")
71	_, ok = peek("k2")
72	uassert.True(t, ok, "k2 protected after Get")
73	_, ok = peek("k3")
74	uassert.False(t, ok, "k3 evicted instead")
75	uassert.Equal(t, capacity, c.size)
76}