Request file handling drops multiple top-level uploaded file fields

[armanist]

Summary

Request currently loses uploaded files when multiple top-level file fields are provided in one multipart request (for example avatar + resume).

Current behavior

Only one top-level file key is processed and stored.

Expected behavior

All top-level file fields should be parsed and available via hasFile() / getFile().

Where this happens

1. src/Http/Traits/Request/File.php

• handleFiles(array $files) reads key($files) and processes only that single field.
• It returns without iterating all top-level keys.

2. src/Http/Request.php

• Real request lifecycle path is affected:
  • populateFromServer() calls setUploadedFiles($rawInputFiles)
  • setUploadedFiles() merges handleFiles($_FILES)
• Because handleFiles($_FILES) processes only one top-level key, real HTTP multipart uploads can also lose sibling file fields.

3. src/Http/Traits/Request/Internal.php

• create() calls setUploadedFiles($this->handleFiles($files)), so internal test request creation is also affected.

Reproduction

Use either:

• real multipart request with multiple top-level file inputs (avatar, resume), or
• Request::create() with the same file structure.

Observed: only one field remains available afterward.

Regression test

Added failing test:

• tests/Unit/Http/Traits/Request/HttpRequestFileTest.php
• testCreateWithMultipleTopLevelFileFields()

Command:

php vendor/bin/phpunit tests/Unit/Http/Traits/Request/HttpRequestFileTest.php --filter testCreateWithMultipleTopLevelFileFields

Observed result:

• Fails with Failed asserting that false is true.

Impact

High correctness impact: forms with multiple independent file inputs are parsed incorrectly, causing silent file loss.

Proposed fix

Update handleFiles() to iterate through all top-level file keys and build a merged uploaded-files map for both:

• single-file fields
• multi-file fields (name as array)