Fixed the handling of empty directories in TrinoHudiStorage.

[smkniazi]

Description

The current implementation throws an error for empty directories, which does not conform to the specifications defined here and here.

With this change, it returns an empty list if the directory is empty and throws an error only if the directory does not exist.

Additional context and related issues

Release notes

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## Section
* Fix some things. ({issue}`issuenumber`)

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[sourcery-ai]

Reviewer's guide (collapsed on small PRs)

Reviewer's Guide

This PR refactors TrinoHudiStorage’s listing methods to conform with Hudi’s API: it now explicitly checks for path existence before listing and returns empty collections for empty directories, only throwing errors when the path is truly missing.

Class diagram for updated TrinoHudiStorage listing methods

classDiagram
class TrinoHudiStorage {
    +boolean createDirectory(StoragePath path)
    +List<StoragePathInfo> listDirectEntries(StoragePath path)
    +List<StoragePathInfo> listDirectEntries(StoragePath path, StoragePathFilter filter)
    +List<StoragePathInfo> listFiles(StoragePath path)
}
TrinoHudiStorage --> FileSystem : uses
TrinoHudiStorage --> FileIterator : uses
TrinoHudiStorage --> StoragePathInfo : returns
TrinoHudiStorage --> StoragePath : parameter
TrinoHudiStorage --> StoragePathFilter : parameter (filtered listing)

Loading

File-Level Changes

Change	Details	Files
Add explicit existence check for storage paths	Introduce exists(path) guard at the start of both listDirectEntries overloads Throw FileNotFoundException when the path does not exist	plugin/trino-hudi/src/main/java/io/trino/plugin/hudi/storage/TrinoHudiStorage.java
Allow empty directory listings without error	Remove the conditional that threw FileNotFoundException when no entries were found Eliminate the entry-counting logic tied to the empty-directory exception	plugin/trino-hudi/src/main/java/io/trino/plugin/hudi/storage/TrinoHudiStorage.java

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[ebyhr]

Could you add a test?

[ebyhr]

Fixed the handling of empty directories in TrinoHudiStorage.

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