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package clock //nolint:testpackage
import "testing"
func TestShardEvictsOldest(t *testing.T) {
t.Parallel()
shard := newShard[string, string](8)
shard.add("a", "a", 4)
shard.add("b", "b", 4)
shard.add("c", "c", 4) // overflows, evicts
if _, ok := shard.peek("a"); ok {
t.Fatalf("a should have been evicted")
}
for _, key := range []string{"b", "c"} {
if _, ok := shard.peek(key); !ok {
t.Fatalf("%s should remain present", key)
}
}
if got := shard.loadWeight(); got != 8 {
t.Fatalf("weight = %d, want 8", got)
}
if got := shard.len(); got != 2 {
t.Fatalf("len = %d, want 2", got)
}
}
func TestShardGetGivesSecondChance(t *testing.T) {
t.Parallel()
shard := newShard[string, string](8)
shard.add("a", "a", 4)
shard.add("b", "b", 4)
shard.add("c", "c", 4) // a evicted; b and c survive
if _, ok := shard.get("b"); !ok {
t.Fatalf("get(b) should hit")
}
shard.add("d", "d", 4) // b was just touched, so c is evicted instead
if _, ok := shard.peek("c"); ok {
t.Fatalf("c should have been evicted after b was touched")
}
for _, key := range []string{"b", "d"} {
if _, ok := shard.peek(key); !ok {
t.Fatalf("%s should remain present", key)
}
}
}
func TestShardPeekGivesNoSecondChance(t *testing.T) {
t.Parallel()
shard := newShard[string, string](8)
shard.add("a", "a", 4)
shard.add("b", "b", 4)
shard.add("c", "c", 4) // a is evicted; b and c survive with cleared bits
if _, ok := shard.peek("b"); !ok {
t.Fatalf("peek(b) should hit")
}
shard.add("d", "d", 4) // peek did not refresh b, so b is evicted
if _, ok := shard.peek("b"); ok {
t.Fatalf("b should have been evicted; peek must not grant a second chance")
}
for _, key := range []string{"c", "d"} {
if _, ok := shard.peek(key); !ok {
t.Fatalf("%s should remain present", key)
}
}
}
func TestShardReplaceUpdatesWeight(t *testing.T) {
t.Parallel()
shard := newShard[string, string](100)
shard.add("a", "old", 4)
shard.add("a", "new", 6)
if got, ok := shard.peek("a"); !ok || got != "new" {
t.Fatalf("peek(a) = (%q, %v), want (new, true)", got, ok)
}
if got := shard.loadWeight(); got != 6 {
t.Fatalf("weight = %d, want 6", got)
}
if got := shard.len(); got != 1 {
t.Fatalf("len = %d, want 1", got)
}
}
func TestShardRejectsOversized(t *testing.T) {
t.Parallel()
shard := newShard[string, string](5)
shard.add("a", "x", 3)
if shard.add("b", "big", 6) {
t.Fatalf("oversized add should report false")
}
if shard.add("a", "huge", 6) {
t.Fatalf("oversized replace should report false")
}
if got, ok := shard.peek("a"); !ok || got != "x" {
t.Fatalf("peek(a) = (%q, %v), want (x, true); cache must be unchanged", got, ok)
}
if _, ok := shard.peek("b"); ok {
t.Fatalf("b must not have been admitted")
}
if got := shard.loadWeight(); got != 3 {
t.Fatalf("weight = %d, want 3", got)
}
}
func TestShardClear(t *testing.T) {
t.Parallel()
shard := newShard[string, string](100)
shard.add("a", "a", 4)
shard.add("b", "b", 4)
shard.clear()
if got := shard.loadWeight(); got != 0 {
t.Fatalf("weight = %d, want 0", got)
}
if got := shard.len(); got != 0 {
t.Fatalf("len = %d, want 0", got)
}
if _, ok := shard.peek("a"); ok {
t.Fatalf("a should be gone after clear")
}
}
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