Add tests for all affected functions in bug-14550 regression test

Cover first-class callable syntax for count, sizeof, strlen, mb_strlen,
preg_match, gettype, get_class, get_debug_type, get_parent_class,
trim, ltrim, rtrim, and array_keys.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

Author: phpstan-bot

tests/PHPStan/Analyser/nsrt/bug-14550.php

@@ -41,3 +41,81 @@ function crashArraySearch(array $list, string $s): void
 	$fn = array_search(...);
 	assertType('Closure(mixed, array, bool=): (int|string|false)', $fn);
 }
+
+function crashCount(): void
+{
+	$fn = count(...);
+	assertType('Closure(array|Countable, 0|1=): int<0, max>', $fn);
+}
+
+function crashSizeof(): void
+{
+	$fn = sizeof(...);
+	assertType('Closure(array|Countable, int=): int', $fn);
+}
+
+function crashStrlen(): void
+{
+	$fn = strlen(...);
+	assertType('Closure(string): int<0, max>', $fn);
+}
+
+function crashMbStrlen(): void
+{
+	$fn = mb_strlen(...);
+	assertType('Closure(string, string|null=): int<0, max>', $fn);
+}
+
+function crashPregMatch(): void
+{
+	$fn = preg_match(...);
+	assertType('Closure(string, string, array<string>|null=, TFlags=, int=): (0|1|false)', $fn);
+}
+
+function crashGettype(): void
+{
+	$fn = gettype(...);
+	assertType('Closure(mixed): string', $fn);
+}
+
+function crashGetClass(): void
+{
+	$fn = get_class(...);
+	assertType('Closure(object=): class-string', $fn);
+}
+
+function crashGetDebugType(): void
+{
+	$fn = get_debug_type(...);
+	assertType('Closure(mixed): string', $fn);
+}
+
+function crashGetParentClass(): void
+{
+	$fn = get_parent_class(...);
+	assertType('Closure(object|string=): (class-string|false)', $fn);
+}
+
+function crashTrim(): void
+{
+	$fn = trim(...);
+	assertType('Closure(string, string=): string', $fn);
+}
+
+function crashLtrim(): void
+{
+	$fn = ltrim(...);
+	assertType('Closure(string, string=): string', $fn);
+}
+
+function crashRtrim(): void
+{
+	$fn = rtrim(...);
+	assertType('Closure(string, string=): string', $fn);
+}
+
+function crashArrayKeys(): void
+{
+	$fn = array_keys(...);
+	assertType('Closure(array, mixed=, bool=): list<int|string>', $fn);
+}