Added array_fill_keys support (#2512)

* Added array_fill_keys support

* Removed unnecessary array_fill_keys phpdoc

src/Psalm/Internal/Analyzer/ProjectAnalyzer.php

@@ -1187,7 +1187,6 @@ class ProjectAnalyzer
 
     public function setAllIssuesToFix(): void
     {
-        /** @var array<string, true> $keyed_issues */
         $keyed_issues = array_fill_keys(static::getSupportedIssuesToFix(), true);
 
         $this->setIssuesToFix($keyed_issues);

src/Psalm/Internal/Fork/Pool.php

@@ -287,7 +287,6 @@ class Pool
 
         // Create an array for the content received on each stream,
         // indexed by resource id.
-        /** @var array<int, string> $content */
         $content = array_fill_keys(array_keys($streams), '');
 
         $terminationMessages = [];

src/Psalm/Internal/Stubs/CoreGenericFunctions.php

@@ -217,3 +217,17 @@ function array_key_exists($key, array $search) : bool
 function array_merge_recursive(array $arr, array ...$arr2)
 {
 }
+
+/**
+ * @psalm-template TKey as array-key
+ * @psalm-template TValue
+ *
+ * @param array<TKey> $keys
+ * @param TValue $value
+ *
+ * @return array<TKey, TValue>
+ * @psalm-pure
+ */
+function array_fill_keys(array $keys, $value): array
+{
+}

tests/FunctionCallTest.php

@@ -2334,6 +2334,14 @@ class FunctionCallTest extends TestCase
                         );
                     }'
             ],
+            'arrayFillKeys' => [
+                '<?php
+                    $keys = [1, 2, 3];
+                    $result = array_fill_keys($keys, true);',
+                'assertions' => [
+                    '$result' => 'array<int, true>',
+                ],
+            ],
         ];
     }