minor #72 chore: remove occurrences of empty() (alexandre-daubois, chr-hertel)

This PR was merged into the main branch.

Discussion
----------

chore: remove occurrences of `empty()`

| Q             | A
| ------------- | ---
| Bug fix?      | no
| New feature?  |no
| Docs?         | no
| Issues        |
| License       | MIT

Cherry picking php-llm/llm-chain#374

Commits
-------

c0d688f chore: use [] checks instead of count with zero on array
fb3d1a8 chore: use isset instead of bool cast on $_ENV
14c448c chore: remove occurrences of `empty()` (#374)

Author: chr-hertel

src/Toolbox/Tool/SimilaritySearch.php

@@ -43,7 +43,7 @@ public function __invoke(string $searchTerm): string
         $vectors = $this->platform->request($this->model, $searchTerm)->asVectors();
         $this->usedDocuments = $this->vectorStore->query($vectors[0]);
 
-        if (0 === \count($this->usedDocuments)) {
+        if ([] === $this->usedDocuments) {
             return 'No results found';
         }
 

src/Toolbox/Tool/Wikipedia.php

@@ -41,7 +41,7 @@ public function search(string $query): string
 
         $titles = array_map(fn (array $item) => $item['title'], $result['query']['search']);
 
-        if (empty($titles)) {
+        if ([] === $titles) {
             return 'No articles were found on Wikipedia.';
         }
 

src/Toolbox/ToolFactory/ReflectionToolFactory.php

@@ -33,7 +33,7 @@ public function getTool(string $reference): iterable
         $reflectionClass = new \ReflectionClass($reference);
         $attributes = $reflectionClass->getAttributes(AsTool::class);
 
-        if (0 === \count($attributes)) {
+        if ([] === $attributes) {
             throw ToolException::missingAttribute($reference);
         }