non-empty-list always has offset 0

phpstan · Apr 24, 2024 · f4d1d48 · f4d1d48
1 parent 26e949b
commit f4d1d48
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Showing 2 changed files with 16 additions and 0 deletions.
diff --git a/src/Type/IntersectionType.php b/src/Type/IntersectionType.php
@@ -26,6 +26,7 @@
 use PHPStan\Type\Accessory\AccessoryNumericStringType;
 use PHPStan\Type\Accessory\AccessoryType;
 use PHPStan\Type\Accessory\NonEmptyArrayType;
+use PHPStan\Type\Constant\ConstantIntegerType;
 use PHPStan\Type\Generic\TemplateType;
 use PHPStan\Type\Generic\TemplateTypeMap;
 use PHPStan\Type\Generic\TemplateTypeVariance;
@@ -673,6 +674,13 @@ public function isOffsetAccessible(): TrinaryLogic
 
 	public function hasOffsetValueType(Type $offsetType): TrinaryLogic
 	{
+		if ($this->isList()->yes() && $this->isIterableAtLeastOnce()->yes()) {
+			$arrayKeyOffsetType = $offsetType->toArrayKey();
+			if ((new ConstantIntegerType(0))->isSuperTypeOf($arrayKeyOffsetType)->yes()) {
+				return TrinaryLogic::createYes();
+			}
+		}
+
 		return $this->intersectResults(static fn (Type $type): TrinaryLogic => $type->hasOffsetValueType($offsetType));
 	}
 

diff --git a/tests/PHPStan/Rules/Arrays/data/report-possibly-nonexistent-array-offset.php b/tests/PHPStan/Rules/Arrays/data/report-possibly-nonexistent-array-offset.php
@@ -49,4 +49,12 @@ public function testDimUnion(array $a, string $dim): void
 		echo $a[$dim];
 	}
 
+	/**
+	 * @param non-empty-list<string> $a
+	 */
+	public function nonEmpty(array $a): void
+	{
+		echo $a[0];
+	}
+
 }