From 3d6a42179375a49e31888da3a645a3a94a65e44d Mon Sep 17 00:00:00 2001
From: Ondrej Mirtes <ondrej@mirtes.cz>
Date: Wed, 1 Sep 2021 11:59:32 +0200
Subject: [PATCH] Change UnionType description if it contains TemplateUnionType

---
 src/Type/UnionType.php                        |  3 +-
 .../Rules/Methods/ReturnTypeRuleTest.php      | 15 ++++++++
 .../Methods/data/return-template-union.php    | 38 +++++++++++++++++++
 tests/PHPStan/Type/TypeCombinatorTest.php     |  2 +-
 4 files changed, 56 insertions(+), 2 deletions(-)
 create mode 100644 tests/PHPStan/Rules/Methods/data/return-template-union.php

diff --git a/src/Type/UnionType.php b/src/Type/UnionType.php
index f1c2ee2aae..d24baf3bbc 100644
--- a/src/Type/UnionType.php
+++ b/src/Type/UnionType.php
@@ -16,6 +16,7 @@
 use PHPStan\Type\Generic\TemplateType;
 use PHPStan\Type\Generic\TemplateTypeMap;
 use PHPStan\Type\Generic\TemplateTypeVariance;
+use PHPStan\Type\Generic\TemplateUnionType;
 
 /** @api */
 class UnionType implements CompoundType
@@ -153,7 +154,7 @@ public function describe(VerbosityLevel $level): string
 		$joinTypes = static function (array $types) use ($level): string {
 			$typeNames = [];
 			foreach ($types as $type) {
-				if ($type instanceof ClosureType || $type instanceof CallableType) {
+				if ($type instanceof ClosureType || $type instanceof CallableType || $type instanceof TemplateUnionType) {
 					$typeNames[] = sprintf('(%s)', $type->describe($level));
 				} elseif ($type instanceof IntersectionType) {
 					$intersectionDescription = $type->describe($level);
diff --git a/tests/PHPStan/Rules/Methods/ReturnTypeRuleTest.php b/tests/PHPStan/Rules/Methods/ReturnTypeRuleTest.php
index 2a59ec2ed7..cdc7ad1b48 100644
--- a/tests/PHPStan/Rules/Methods/ReturnTypeRuleTest.php
+++ b/tests/PHPStan/Rules/Methods/ReturnTypeRuleTest.php
@@ -512,4 +512,19 @@ public function testBug3151(): void
 		$this->analyse([__DIR__ . '/data/bug-3151.php'], []);
 	}
 
+	public function testTemplateUnion(): void
+	{
+		$this->analyse([__DIR__ . '/data/return-template-union.php'], [
+			[
+				'Method ReturnTemplateUnion\Foo::doFoo2() should return T of bool|float|int|string but returns (T of bool|float|int|string)|null.',
+				25,
+			],
+			[
+				// should not be reported
+				'Method ReturnTemplateUnion\Foo::doFoo3() should return (T of bool|float|int|string)|null but returns (T of bool|float|int|string)|null.',
+				35,
+			],
+		]);
+	}
+
 }
diff --git a/tests/PHPStan/Rules/Methods/data/return-template-union.php b/tests/PHPStan/Rules/Methods/data/return-template-union.php
new file mode 100644
index 0000000000..a154bfd03d
--- /dev/null
+++ b/tests/PHPStan/Rules/Methods/data/return-template-union.php
@@ -0,0 +1,38 @@
+<?php
+
+namespace ReturnTemplateUnion;
+
+class Foo
+{
+
+	/**
+	 * @template T of bool|string|int|float
+	 * @param T $p
+	 * @return T
+	 */
+	public function doFoo($p)
+	{
+		return $p;
+	}
+
+	/**
+	 * @template T of bool|string|int|float
+	 * @param T|null $p
+	 * @return T
+	 */
+	public function doFoo2($p)
+	{
+		return $p;
+	}
+
+	/**
+	 * @template T of bool|string|int|float
+	 * @param T|null $p
+	 * @return T|null
+	 */
+	public function doFoo3($p)
+	{
+		return $p;
+	}
+
+}
diff --git a/tests/PHPStan/Type/TypeCombinatorTest.php b/tests/PHPStan/Type/TypeCombinatorTest.php
index 59770b3320..54f20414d4 100644
--- a/tests/PHPStan/Type/TypeCombinatorTest.php
+++ b/tests/PHPStan/Type/TypeCombinatorTest.php
@@ -1820,7 +1820,7 @@ public function dataUnion(): array
 					new NullType(),
 				],
 				UnionType::class,
-				'T of bool|float|int|string (function doFoo(), parameter)|null',
+				'(T of bool|float|int|string (function doFoo(), parameter))|null',
 			],
 		];
 	}