Fix #4759 – don’t generate assertion when assigning to same-named variable

src/Psalm/Internal/Analyzer/Statements/Expression/AssignmentAnalyzer.php

@@ -1884,6 +1884,11 @@ class AssignmentAnalyzer
                         $codebase
                     );
 
+                    $right_clauses = Context::filterClauses(
+                        $var_id,
+                        $right_clauses
+                    );
+
                     $assignment_clauses = \Psalm\Internal\Algebra::combineOredClauses(
                         [new \Psalm\Internal\Clause([$var_id => ['falsy']], $var_object_id, $var_object_id)],
                         $right_clauses,

tests/TypeReconciliation/TypeAlgebraTest.php

@@ -1052,6 +1052,13 @@ class TypeAlgebraTest extends \Psalm\Tests\TestCase
                         }
                     }'
             ],
+            'assignSameName' => [
+                '<?php
+                    function foo(string $value): string {
+                        $value = "yes" === $value;
+                        return !$value ? "foo" : "bar";
+                    }'
+            ],
         ];
     }