# fix: only treat the last path segment as a filename in path()

## Problem

`TemporaryDirectory::path()` fails to create a requested subdirectory when the
temporary directory's location contains a dot:

```php
$tmp = (new Spatie\TemporaryDirectory\TemporaryDirectory('/tmp/my.app'))
    ->name('run1')
    ->create();

$path = $tmp->path('abc');   // "abc" is a directory
is_dir($path);               // false  <-- the directory was not created
```

`path('abc')` is documented and tested to create the `abc` subdirectory (see
`it_can_create_a_subdirectory_in_the_temporary_directory`), but here it returns a
path whose directory does not exist.

## Root cause

`src/TemporaryDirectory.php`. `path()` decides whether the argument points to a
file (create only the parent directory) or a directory (create the whole path)
via `isFilePath()`:

```php
protected function isFilePath(string $path): bool
{
    return str_contains($path, '.');
}
```

`$path` is the full path (`location + name + argument`), so the check reacts to a
dot anywhere in it - including a dot in the location such as `/tmp/my.app`. When
that happens, a directory argument like `abc` is misclassified as a file, and
`removeFilenameFromPath()` strips the `abc` segment, so only the already existing
parent is created and `abc` is skipped.

## The fix

Only the last path segment can be a filename, so inspect just that segment:

```php
protected function isFilePath(string $path): bool
{
    $lastSeparator = strrpos($path, DIRECTORY_SEPARATOR);
    $lastSegment = $lastSeparator === false ? $path : substr($path, $lastSeparator + 1);

    return str_contains($lastSegment, '.');
}
```

A dot in a parent segment (the location or name) no longer affects the
file/directory decision, while a real filename such as `test.txt` in the last
segment is still detected.

## Test

Added `it_can_create_a_subdirectory_when_the_location_contains_a_dot`, which
creates a temporary directory under a location containing dots and asserts that
`path('abc')` actually creates the `abc` directory.

## Gate

```
composer install && vendor/bin/phpunit
```

Result: exit code `0` - `OK (23 tests, 37 assertions)`.

Counterfactual: reverting `isFilePath()` to `str_contains($path, '.')` makes the
new test fail - `Failed asserting that directory
"/tmp/my.dotted.location/temporary_directory/abc" exists`.