diff --git a/src/Psalm/Internal/Analyzer/Statements/Expression/Assignment/ArrayAssignmentAnalyzer.php b/src/Psalm/Internal/Analyzer/Statements/Expression/Assignment/ArrayAssignmentAnalyzer.php
index abb31467d..fa0e16e33 100644
--- a/src/Psalm/Internal/Analyzer/Statements/Expression/Assignment/ArrayAssignmentAnalyzer.php
+++ b/src/Psalm/Internal/Analyzer/Statements/Expression/Assignment/ArrayAssignmentAnalyzer.php
@@ -590,6 +590,11 @@ class ArrayAssignmentAnalyzer
                         $array_atomic_type_class_string->getStandinKeyParam(),
                         $array_atomic_type_class_string->value_param
                     ]);
+                } elseif ($atomic_root_types['array'] instanceof TKeyedArray
+                    && $atomic_root_types['array']->is_list
+                    && $atomic_root_types['array']->fallback_params === null
+                ) {
+                    $array_atomic_type = $atomic_root_types['array'];
                 } elseif ($atomic_root_types['array'] instanceof TNonEmptyArray
                     || ($atomic_root_types['array'] instanceof TKeyedArray
                         && $atomic_root_types['array']->is_list
diff --git a/tests/ArrayAssignmentTest.php b/tests/ArrayAssignmentTest.php
index 30084237f..e835fcec9 100644
--- a/tests/ArrayAssignmentTest.php
+++ b/tests/ArrayAssignmentTest.php
@@ -2011,6 +2011,21 @@ class ArrayAssignmentTest extends TestCase
                 if (\array_key_exists($currentAction, $items)) {
                     $items[$currentAction]["active"] = true;
                 }'
+            ],
+            'listAppendShape' => [
+                'code' => '<?php
+                    $a = [];
+                    $a[]= 0;
+                    $a[]= 1;
+                    $a[]= 2;
+
+                    $b = [0];
+                    $b[]= 1;
+                    $b[]= 2;',
+                'assertions' => [
+                    '$a===' => 'list{0, 1, 2}',
+                    '$b===' => 'list{0, 1, 2}'
+                ]
             ]
         ];
     }