Set doesn't reset TTL if the key already exists

[vsavicks]

According to the docs of the Set() method:

If an item associated with the provided key already exists, the new item overwrites the existing one.

However, if I try to set an item that already exists but has an expired TTL and delete all expired, the newly set item also gets deleted:

package main

import (
	"fmt"
	"time"

	"github.com/jellydator/ttlcache/v3"
)

func main() {
	cache := ttlcache.New[string](
		ttlcache.WithTTL[string, string](1 * time.Second),
	)
	cache.Set("foo", "bar", ttlcache.DefaultTTL)
	fmt.Printf("first: %s\n", cache.Keys())

	time.Sleep(2 * time.Second)
	fmt.Printf("after 2s: %s\n", cache.Keys())

	cache.DeleteExpired()
	fmt.Printf("after delete: %s\n", cache.Keys())

	cache.Set("baz", "qux", ttlcache.DefaultTTL)
	fmt.Printf("new: %s\n", cache.Keys())

	time.Sleep(2 * time.Second)
	fmt.Printf("after 2s: %s\n", cache.Keys())

	cache.Set("baz", "qum", ttlcache.DefaultTTL)
	cache.DeleteExpired()
	fmt.Printf("after set and delete: %s\n", cache.Keys())
}

Output:

first: [foo]
after 2s: [foo]
after delete: []
new: [baz]
after 2s: [baz]
after set and delete: []

I would expect the replaced item to have new TTL and not get deleted by DeleteExpired() call.

[swithek]

Thanks for reporting this @vsavicks. We'll try to have it fixed soon.

[QisFj]

just to provide some infomation.

I can't reproduce it at:

go version go1.23.5 darwin/arm64
github.com/jellydator/ttlcache/[email protected]

same code. but the output is:

first: [foo]
after 2s: []
after delete: []
new: [baz]
after 2s: []
after set and delete: [baz]