Hello. Does anyone know the justification for <kot...

# stdlib

[mikehearn]

Hello. Does anyone know the justification for kotlin.io being a set of extensions to java.io.File instead of java.nio.file.Path ? I assume this is to do with the legacy Java 1.6 support but it's quite awkward for programs that want to benefit from the NIO features like in-memory file systems, etc.

[nfrankel]

that’s a great question indeed 💡

[ephemient]

there are extensions to nio.file, https://kotlinlang.org/api/latest/jvm/stdlib/kotlin.io.path/java.nio.file.-path/

[ephemient]

you must have a new enough jvm target but that should be the default now

[mikehearn]

Yes, but e.g. walkFileTree is only on File

[ephemient]

a Kotlin wrapper isn't as useful for Path since there's Files.walkFileTree, IMO. but you could file a YT issue if you think there's a reason for it

[mikehearn]

The Kotlin code has a quite nice function to do bottoms-up as well as top-down walks. But yeah it's a minor thing I guess.

[jw]

It was dropped from the initial NIO extension PR. Feel free to send one focusing solely on adding that where we can discuss the right API.

[ephemient]

oh I see: https://github.com/JetBrains/kotlin/pull/3344#issuecomment-696156526

[pniederw]

These are the gaps that we still use our own extensions methods for:

Path.walk()           // -> Files.walk()
Path.createTempFile() // -> Files.createTempFile()
Path.writeString()    // -> Files.writeString() (more efficient than Path.writeText())
Path.readString()     // -> Files.readString() (more efficient than Path.readText())
Path.deleteRecursively() // -> Files.walk()
Path.createParentDirectories() // dedicated method because we need this a lot

[rnett]

These would all be nice to have, imo, except maybe the last one which could possibly be done as Path.parent.mkdir(true) or similar

[ephemient]

path.parent?.createDirectories() but yeah, those sound good to raise somewhere more formal

[pniederw]

the last one is a convenience method that we use all over the place:

fun Path.createParentDirectories(vararg attributes: FileAttribute<*>): Path =
  apply { parent?.createDirectories(*attributes) }

[pniederw]

usage: path.createParentDirectories().writeString("hello")

[mikehearn]

Thanks all, very helpful.

[mikehearn]

Seems it's just waiting for someone to step up and submit PRs.