diff --git a/tests/PHPStan/Analyser/NodeScopeResolverTest.php b/tests/PHPStan/Analyser/NodeScopeResolverTest.php
index dabbc6dca5..fbb7291d0d 100644
--- a/tests/PHPStan/Analyser/NodeScopeResolverTest.php
+++ b/tests/PHPStan/Analyser/NodeScopeResolverTest.php
@@ -83,6 +83,8 @@ public function dataFileAsserts(): iterable
 		yield from $this->gatherAssertTypes(__DIR__ . '/data/list-type.php');
 		yield from $this->gatherAssertTypes(__DIR__ . '/data/bug-2835.php');
 		yield from $this->gatherAssertTypes(__DIR__ . '/data/bug-2443.php');
+		yield from $this->gatherAssertTypes(__DIR__ . '/data/bug-5508.php');
+		yield from $this->gatherAssertTypes(__DIR__ . '/data/bug-10254.php');
 		yield from $this->gatherAssertTypes(__DIR__ . '/data/bug-2750.php');
 		yield from $this->gatherAssertTypes(__DIR__ . '/data/bug-2850.php');
 		yield from $this->gatherAssertTypes(__DIR__ . '/data/bug-2863.php');
diff --git a/tests/PHPStan/Analyser/data/bug-10254.php b/tests/PHPStan/Analyser/data/bug-10254.php
new file mode 100644
index 0000000000..3299015ca0
--- /dev/null
+++ b/tests/PHPStan/Analyser/data/bug-10254.php
@@ -0,0 +1,91 @@
+<?php
+
+namespace Bug10254;
+
+use Closure;
+use RuntimeException;
+use function PHPStan\Testing\assertType;
+
+/**
+ * @template T
+ */
+class Option {
+	/**
+	 * @param T $value
+	 */
+	private function __construct(private mixed $value)
+	{
+	}
+
+	/**
+	 * @template Tv
+	 * @param Tv $value
+	 * @return self<Tv>
+	 */
+	public static function some($value): self
+	{
+		return new self($value);
+	}
+
+	/**
+	 * @template Tu
+	 *
+	 * @param (Closure(T): Tu) $closure
+	 *
+	 * @return Option<Tu>
+	 */
+	public function map(Closure $closure): self
+	{
+		return new self($closure($this->unwrap()));
+	}
+
+	/**
+	 * @return T
+	 */
+	public function unwrap()
+	{
+		if ($this->value === null) {
+			throw new RuntimeException();
+		}
+
+		return $this->value;
+	}
+
+	/**
+	 * @template To
+	 * @param self<To> $other
+	 * @return self<array{0: T, 1: To}>
+	 */
+	public function zip(self $other)
+	{
+		return new self([
+			$this->unwrap(),
+			$other->unwrap()
+		]);
+	}
+}
+
+
+function (): void {
+	$value = Option::some(1)
+		->zip(Option::some(2));
+
+	assertType('Bug10254\\Option<array{int, int}>', $value);
+
+	$value1 = $value->map(function ($value) {
+		assertType('int', $value[0]);
+		assertType('int', $value[1]);
+		return $value[0] + $value[1];
+	});
+
+	assertType('Bug10254\\Option<int>', $value1);
+
+	$value2 = $value->map(function ($value): int {
+		assertType('int', $value[0]);
+		assertType('int', $value[1]);
+		return $value[0] + $value[1];
+	});
+
+	assertType('Bug10254\\Option<int>', $value2);
+
+};
diff --git a/tests/PHPStan/Analyser/data/bug-5508.php b/tests/PHPStan/Analyser/data/bug-5508.php
new file mode 100644
index 0000000000..89af5b4b98
--- /dev/null
+++ b/tests/PHPStan/Analyser/data/bug-5508.php
@@ -0,0 +1,57 @@
+<?php
+
+namespace Bug5508;
+
+use function PHPStan\Testing\assertType;
+
+/**
+ * @template TKey as array-key
+ * @template TValue
+ */
+class Collection
+{
+	/**
+	 * @var array<TKey, TValue>
+	 */
+	protected $items = [];
+
+	/**
+	 * @param  array<TKey, TValue>  $items
+	 * @return void
+	 */
+	public function __construct($items)
+	{
+		$this->items = $items;
+	}
+
+	/**
+	 * @template TMapValue
+	 *
+	 * @param  callable(TValue, TKey): TMapValue  $callback
+	 * @return self<TKey, TMapValue>
+	 */
+	public function map(callable $callback)
+	{
+		$keys = array_keys($this->items);
+
+		$items = array_map($callback, $this->items, $keys);
+
+		return new self(array_combine($keys, $items));
+	}
+
+	/**
+	 * @return array<TKey, TValue>
+	 */
+	public function all()
+	{
+		return $this->items;
+	}
+}
+
+function (): void {
+	$result = (new Collection(['book', 'cars']))->map(function($category) {
+		return $category;
+	})->all();
+
+	assertType('array<int, string>', $result);
+};
diff --git a/tests/PHPStan/Rules/Functions/ReturnTypeRuleTest.php b/tests/PHPStan/Rules/Functions/ReturnTypeRuleTest.php
index bb99cc426a..646b96d968 100644
--- a/tests/PHPStan/Rules/Functions/ReturnTypeRuleTest.php
+++ b/tests/PHPStan/Rules/Functions/ReturnTypeRuleTest.php
@@ -276,4 +276,11 @@ public function testBug5592(): void
 		$this->analyse([__DIR__ . '/data/bug-5592.php'], []);
 	}
 
+	public function testBug10732(): void
+	{
+		$this->checkExplicitMixed = true;
+		$this->checkNullables = true;
+		$this->analyse([__DIR__ . '/data/bug-10732.php'], []);
+	}
+
 }
diff --git a/tests/PHPStan/Rules/Functions/data/bug-10732.php b/tests/PHPStan/Rules/Functions/data/bug-10732.php
new file mode 100644
index 0000000000..daabd2c88a
--- /dev/null
+++ b/tests/PHPStan/Rules/Functions/data/bug-10732.php
@@ -0,0 +1,77 @@
+<?php
+
+namespace Bug10732;
+
+/**
+ * @template-covariant TValue
+ */
+class Collection
+{
+	/**
+	 * Create a new collection.
+	 *
+	 * @param list<TValue> $items
+	 * @return void
+	 */
+	public function __construct(protected array $items = []) {}
+
+	/**
+	 * Run a map over each of the items.
+	 *
+	 * @template TMapValue
+	 *
+	 * @param  callable(TValue): TMapValue  $callback
+	 * @return static<TMapValue>
+	 */
+	public function map(callable $callback)
+	{
+		return new self(array_map($callback, $this->items));
+	}
+}
+
+/**
+ * I'd expect this to work?
+ *
+ * @param Collection<array<string,  mixed>> $collection
+ * @return Collection<array<string,  mixed>>
+ */
+function current(Collection $collection): Collection
+{
+	return $collection->map(fn(array $item) => $item);
+}
+
+/**
+ * Removing the Typehint works
+ *
+ * @param Collection<array<string,  mixed>> $collection
+ * @return Collection<array<string,  mixed>>
+ */
+function removeTypeHint(Collection $collection): Collection
+{
+	return $collection->map(fn($item) => $item);
+}
+
+/**
+ * Typehint works for simple type
+ *
+ * @param Collection<string> $collection
+ * @return Collection<string>
+ */
+function simplerType(Collection $collection): Collection
+{
+	return $collection->map(fn(string $item) => $item);
+}
+
+/**
+ * Typehint works for arrays
+ *
+ * @param array<string, array<string,  mixed>> $collection
+ * @return array<string, array<string,  mixed>>
+ */
+function useArraysInstead(array $collection): array
+{
+	return array_map(
+		fn(array $item) => $item,
+		$collection,
+	);
+}