Always remove callable type

src/Psalm/Type/Reconciler.php

@@ -1748,6 +1748,8 @@ class Reconciler
         }
 
         if ($new_var_type === 'callable') {
+            $existing_var_type->removeType('callable');
+
             foreach ($existing_var_atomic_types as $atomic_key => $type) {
                 if ($type instanceof Type\Atomic\TLiteralString
                     && \Psalm\Internal\Codebase\CallMap::inCallMap($type->value)

tests/TypeReconciliationTest.php

@@ -1230,6 +1230,27 @@ class TypeReconciliationTest extends TestCase
                         echo $a;
                     }',
             ],
+            'removeCallableWithAssertion' => [
+                '<?php
+                    /**
+                     * @param mixed $p
+                     * @psalm-assert !callable $p
+                     * @throws TypeError
+                     */
+                    function assertIsNotCallable($p): void { if (!is_callable($p)) throw new TypeError; }
+
+                    /** @return callable|float */
+                    function f() { return rand(0,1) ? "f" : 1.1; }
+
+                    $a = f();
+                    assert(!is_callable($a));
+
+                    $b = f();
+                    assertIsNotCallable($b);
+
+                    atan($a);
+                    atan($b);',
+            ],
             'PHP71-removeNonCallable' => [
                 '<?php
                     $f = rand(0, 1) ? "strlen" : 1.1;