fix: mergeIfMissing function:

[techmahedy]

Problem

When using mergeIfMissing() (or any method that internally calls has() or input() before mutating request data), the local $this->input cache gets populated and locked. Any subsequent merge into the underlying InputBag is invisible to input(), has(), and the __get() magic method because they all read from the stale cache.

Minimal reproduction:

$request->mergeIfMissing(['test' => 'doppar']);

$request->all();   // returns merged data (reads directly from InputBag)
$request->test;    // returns null (reads from stale cache)
$request->input('test'); // returns `null`
$request->has('test');   // returns `false`

input() and has() in RequestHelper lazily populate $this->input on first access and never invalidate it:

Fix

Invalidate $this->input cache inside merge() so any subsequent read re-fetches fresh data from the underlying InputBag:

public function merge(array $input): self
{
    $this->request->replace(array_merge($this->request->all(), $input));
    $this->input = []; // invalidate stale cache

    return $this;
}

Also fixed

public function nullifyBlanks(...): static
{
    // ...existing logic...
    $this->request->replace($data);
    $this->input = []; // invalidate stale cache

    return $this;
}

The targeted invalidation approach is the minimal, lowest-risk fix — it preserves the intended optimization while correcting the staleness bug.