Fix issue creating empty array offsets

vimeo · Oct 9, 2019 · e620c2c · e620c2c
1 parent db33efb
commit e620c2c
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Showing 2 changed files with 39 additions and 2 deletions.
diff --git a/src/Psalm/Type/Reconciler.php b/src/Psalm/Type/Reconciler.php
@@ -168,6 +168,7 @@ public static function reconcileKeyedTypes(
             $has_isset = false;
             $has_inverted_isset = false;
             $has_falsyish = false;
+            $has_empty = false;
             $has_count_check = false;
 
             foreach ($new_type_parts as $new_type_part_parts) {
@@ -186,6 +187,8 @@ public static function reconcileKeyedTypes(
                         || $new_type_part_part === '=isset'
                         || $new_type_part_part === 'array-key-exists';
 
+                    $has_empty = $has_empty || $new_type_part_part === 'empty';
+
                     $has_falsyish = $has_falsyish
                         || $new_type_part_part === 'empty'
                         || $new_type_part_part === 'falsy';
@@ -204,7 +207,8 @@ public static function reconcileKeyedTypes(
                     $key,
                     $existing_types,
                     $code_location,
-                    $has_isset
+                    $has_isset,
+                    $has_empty
                 );
 
             if ($result_type && empty($result_type->getTypes())) {
@@ -417,7 +421,8 @@ private static function getValueForKey(
         string $key,
         array &$existing_keys,
         ?CodeLocation $code_location,
-        bool $has_isset
+        bool $has_isset,
+        bool $has_empty
     ) {
         $key_parts = self::breakUpPathIntoParts($key);
 
@@ -462,12 +467,20 @@ private static function getValueForKey(
 
                     foreach ($existing_keys[$base_key]->getTypes() as $existing_key_type_part) {
                         if ($existing_key_type_part instanceof Type\Atomic\TArray) {
+                            if ($has_empty) {
+                                return null;
+                            }
+
                             $new_base_type_candidate = clone $existing_key_type_part->type_params[1];
 
                             if ($has_isset) {
                                 $new_base_type_candidate->possibly_undefined = true;
                             }
                         } elseif ($existing_key_type_part instanceof Type\Atomic\TList) {
+                            if ($has_empty) {
+                                return null;
+                            }
+
                             $new_base_type_candidate = clone $existing_key_type_part->type_param;
 
                             if ($has_isset) {
@@ -476,6 +489,10 @@ private static function getValueForKey(
                         } elseif (!$existing_key_type_part instanceof Type\Atomic\ObjectLike) {
                             return Type::getMixed();
                         } elseif ($array_key[0] === '$') {
+                            if ($has_empty) {
+                                return null;
+                            }
+
                             $new_base_type_candidate = $existing_key_type_part->getGenericValueType();
                         } else {
                             $array_properties = $existing_key_type_part->properties;

diff --git a/tests/AssertTest.php b/tests/AssertTest.php
@@ -338,6 +338,26 @@ public function bar(array $args) : void {
                         }
                     }'
             ],
+            'assertNotEmptyOnArray' => [
+                '<?php
+                    function foo(bool $c, array $arr) : void {
+                        if ($c && !empty($arr["b"])) {
+                            return;
+                        }
+
+                        if ($c && rand(0, 1)) {}
+                    }'
+            ],
+            'assertIssetOnArray' => [
+                '<?php
+                    function foo(bool $c, array $arr) : void {
+                        if ($c && $arr && isset($arr["b"]) && $arr["b"]) {
+                            return;
+                        }
+
+                        if ($c && rand(0, 1)) {}
+                    }'
+            ],
         ];
     }
 }