Disk Cache Not Working w/ 3.0.0-alpha3

[herriojr]

With Picasso 3.0.0-alpha3, when I do the following:

            picasso.load("https://some/image/url")
                .memoryPolicy(MemoryPolicy.NO_CACHE, MemoryPolicy.NO_STORE)
                .fetch(object : Callback {
                    override fun onError(t: Throwable) {
                        Log.d("TAG", "Failed")
                        t.printStackTrace()
                    }

                    override fun onSuccess() {
                        Log.d("TAG", "Success")
                    }
                })

If I wait for the fetch to succeed, then do the following:

            picasso.load("https://some/image/url")
                .memoryPolicy(MemoryPolicy.NO_CACHE, MemoryPolicy.NO_STORE)
                .networkPolicy(NetworkPolicy.OFFLINE)
                .fetch(object : Callback {
                    override fun onError(t: Throwable) {
                        Log.d("TAG", "Failed")
                        t.printStackTrace()
                    }

                    override fun onSuccess() {
                        Log.d("TAG", "Success")
                    }
                })

The second fetch fails with a 504. It appears that even though the first fetch() was supposed to disk cache, it never actually does. When I look into it further, it appears the currentEditor on the DiskLruCache's entity is not being completed at all and just gets stuck open. I don't know exactly where, but it appears that the source needs to be closed so the cached item can be committed.

Further investigation shows that the disk cache just isn't being used at all in api 26, which I'm assuming it's api < 28 that has this issue since that's the only version check I see in the picasso codebase.