Preserve constant array when setting a integer-range key

Author: staabm

src/Type/Constant/ConstantArrayType.php

@@ -700,7 +700,12 @@ public function getOffsetValueType(Type $offsetType): Type
 	public function setOffsetValueType(?Type $offsetType, Type $valueType, bool $unionValues = true): Type
 	{
 		if ($offsetType !== null && $valueType->isConstantScalarValue()->yes()) {
-			$constantScalars = $offsetType->getConstantScalarTypes();
+			if ($offsetType instanceof IntegerRangeType) {
+				$constantScalars = $offsetType->getFiniteTypes();
+			} else {
+				$constantScalars = $offsetType->getConstantScalarTypes();
+			}
+
 			$constantScalarsCount = count($constantScalars);
 			if ($constantScalarsCount > 1 && $constantScalarsCount < ConstantArrayTypeBuilder::ARRAY_COUNT_LIMIT) {
 				$arrays = [];
@@ -722,7 +727,12 @@ public function setOffsetValueType(?Type $offsetType, Type $valueType, bool $uni
 	public function setExistingOffsetValueType(Type $offsetType, Type $valueType): Type
 	{
 		if ($valueType->isConstantScalarValue()->yes()) {
-			$constantScalars = $offsetType->getConstantScalarTypes();
+			if ($offsetType instanceof IntegerRangeType) {
+				$constantScalars = $offsetType->getFiniteTypes();
+			} else {
+				$constantScalars = $offsetType->getConstantScalarTypes();
+			}
+
 			$constantScalarsCount = count($constantScalars);
 			if ($constantScalarsCount > 1 && $constantScalarsCount < ConstantArrayTypeBuilder::ARRAY_COUNT_LIMIT) {
 				$arrays = [];

tests/PHPStan/Analyser/nsrt/constant-array-type-set.php

@@ -27,7 +27,7 @@ public function doFoo(int $i)
 		/** @var int<0, 2> $offset2 */
 		$offset2 = doFoo();
 		$d[$offset2] = true;
-		assertType('array{bool, bool, bool}', $d);
+		assertType('array{false, false, true}|array{false, true, false}|array{true, false, false}', $d);
 
 		$e = [false, false, false];
 		/** @var 0|1|2|3 $offset3 */
@@ -50,7 +50,7 @@ public function doBar(int $offset): void
 	{
 		$a = [false, false, false];
 		$a[$offset] = true;
-		assertType('array{bool, bool, false}', $a);
+		assertType('array{false, true, false}|array{true, false, false}', $a);
 	}
 
 	/**
@@ -94,7 +94,7 @@ public function doBar5(int $offset): void
 	{
 		$a = [false, false, false];
 		$a[$offset] = true;
-		assertType('non-empty-array<int<0, 4>, bool>', $a);
+		assertType('array{0: false, 1: false, 2: false, 4: true}|array{false, false, false, true}|array{false, false, true}|array{false, true, false}|array{true, false, false}', $a);
 	}
 
 	public function doBar6(bool $offset): void

tests/PHPStan/Analyser/nsrt/set-constant-union-offset-on-constant-array.php

@@ -17,4 +17,14 @@ public function doFoo(array $a): void
 		assertType('array{foo: int, a: 256}|array{foo: int, b: 256}', $a);
 	}
 
+	/**
+	 * @param array{foo: int}  $a
+	 * @param int<1,5> $intRange
+	 */
+	public function doBar(array $a, $intRange): void
+	{
+		$a[$intRange] = 256;
+		assertType('array{foo: int, 1: 256}|array{foo: int, 2: 256}|array{foo: int, 3: 256}|array{foo: int, 4: 256}|array{foo: int, 5: 256}', $a);
+	}
+
 }