Fix wrong tip about returning a list

Closes phpstan/phpstan#10077

src/Type/Accessory/AccessoryArrayListType.php

@@ -26,7 +26,6 @@
 use PHPStan\Type\TypeCombinator;
 use PHPStan\Type\UnionType;
 use PHPStan\Type\VerbosityLevel;
-use function sprintf;
 
 /** @api */
 class AccessoryArrayListType implements CompoundType, AccessoryType
@@ -89,17 +88,8 @@ public function acceptsWithReason(Type $type, bool $strictTypes): AcceptsResult
 
 		$isArray = $type->isArray();
 		$isList = $type->isList();
-		$reasons = [];
-		if ($isArray->yes() && !$isList->yes()) {
-			$verbosity = VerbosityLevel::getRecommendedLevelByType($this, $type);
-			$reasons[] = sprintf(
-				'%s %s a list.',
-				$type->describe($verbosity),
-				$isList->no() ? 'is not' : 'might not be',
-			);
-		}
 
-		return new AcceptsResult($isArray->and($isList), $reasons);
+		return new AcceptsResult($isArray->and($isList), []);
 	}
 
 	public function isSuperTypeOf(Type $type): TrinaryLogic

src/Type/IntersectionType.php

@@ -189,6 +189,20 @@ public function acceptsWithReason(Type $otherType, bool $strictTypes): AcceptsRe
 			$result = $result->and($type->acceptsWithReason($otherType, $strictTypes));
 		}
 
+		if (!$result->yes()) {
+			$isList = $otherType->isList();
+			if ($this->isList()->yes() && !$isList->yes()) {
+				$verbosity = VerbosityLevel::getRecommendedLevelByType($this, $otherType);
+				return new AcceptsResult($result->result, [
+					sprintf(
+						'%s %s a list.',
+						$otherType->describe($verbosity),
+						$isList->no() ? 'is not' : 'might not be',
+					),
+				]);
+			}
+		}
+
 		return $result;
 	}
 

tests/PHPStan/Rules/Functions/ReturnTypeRuleTest.php

@@ -231,4 +231,16 @@ public function testBug8846(): void
 		$this->analyse([__DIR__ . '/data/bug-8846.php'], []);
 	}
 
+	public function testBug10077(): void
+	{
+		$this->checkExplicitMixed = true;
+		$this->checkNullables = true;
+		$this->analyse([__DIR__ . '/data/bug-10077.php'], [
+			[
+				'Function Bug10077\mergeMediaQueries() should return list<Bug10077\CssMediaQuery>|null but returns list<Bug10077\MediaQueryMergeResult>.',
+				56,
+			],
+		]);
+	}
+
 }

tests/PHPStan/Rules/Functions/data/bug-10077.php

@@ -0,0 +1,57 @@
+<?php
+
+namespace Bug10077;
+
+interface MediaQueryMergeResult
+{
+}
+
+
+enum MediaQuerySingletonMergeResult implements MediaQueryMergeResult
+{
+	case empty;
+	case unrepresentable;
+}
+
+// In actual code, this is a final class implementing its methods
+abstract class CssMediaQuery implements MediaQueryMergeResult
+{
+	abstract public function merge(CssMediaQuery $other): MediaQueryMergeResult;
+}
+
+
+/**
+ * Returns a list of queries that selects for contexts that match both
+ * $queries1 and $queries2.
+ *
+ * Returns the empty list if there are no contexts that match both $queries1
+ * and $queries2, or `null` if there are contexts that can't be represented
+ * by media queries.
+ *
+ * @param CssMediaQuery[] $queries1
+ * @param CssMediaQuery[] $queries2
+ *
+ * @return list<CssMediaQuery>|null
+ */
+function mergeMediaQueries(array $queries1, array $queries2): ?array
+{
+	$queries = [];
+
+	foreach ($queries1 as $query1) {
+		foreach ($queries2 as $query2) {
+			$result = $query1->merge($query2);
+
+			if ($result === MediaQuerySingletonMergeResult::empty) {
+				continue;
+			}
+
+			if ($result === MediaQuerySingletonMergeResult::unrepresentable) {
+				return null;
+			}
+
+			$queries[] = $result;
+		}
+	}
+
+	return $queries;
+}

tests/PHPStan/Rules/Methods/ReturnTypeRuleTest.php

@@ -955,4 +955,14 @@ public function testBug9766(): void
 		$this->analyse([__DIR__ . '/data/bug-9766.php'], []);
 	}
 
+	public function testWrongListTip(): void
+	{
+		$this->analyse([__DIR__ . '/data/wrong-list-tip.php'], [
+			[
+				'Method WrongListTip\Test::doFoo() should return list<WrongListTip\Foo> but returns list<WrongListTip\Bar>.',
+				23,
+			],
+		]);
+	}
+
 }

tests/PHPStan/Rules/Methods/data/wrong-list-tip.php

@@ -0,0 +1,34 @@
+<?php
+
+namespace WrongListTip;
+
+interface Foo
+{
+
+}
+
+interface Bar
+{
+
+}
+
+class Test
+{
+
+	/**
+	 * @return list<Foo>
+	 */
+	public function doFoo(): array
+	{
+		return $this->listOfBars();
+	}
+
+	/**
+	 * @return list<Bar>
+	 */
+	public function listOfBars(): array
+	{
+		return [];
+	}
+
+}

tests/PHPStan/Rules/Properties/TypesAssignedToPropertiesRuleTest.php

@@ -515,7 +515,7 @@ public function testBug3311b(): void
 			[
 				'Property Bug3311b\Foo::$bar (list<string>) does not accept non-empty-array<int<0, max>, string>.',
 				16,
-				'array<int<0, max>, string> might not be a list.',
+				'non-empty-array<int<0, max>, string> might not be a list.',
 			],
 		]);
 	}