More precise array_keys return type

Author: staabm

src/Type/Accessory/AccessoryArrayListType.php

@@ -172,6 +172,11 @@ public function unsetOffset(Type $offsetType): Type
 return new ErrorType();
 }
 
+public function getKeysArrayFiltered(Type $filterValueType, TrinaryLogic $strict): Type
+{
+return $this->getKeysArray();
+}
+
 public function getKeysArray(): Type
 {
 return $this;

src/Type/Accessory/HasOffsetType.php

@@ -352,6 +352,11 @@ public function looseCompare(Type $type, PhpVersion $phpVersion): BooleanType
 return new BooleanType();
 }
 
+public function getKeysArrayFiltered(Type $filterValueType, TrinaryLogic $strict): Type
+{
+return $this->getKeysArray();
+}
+
 public function getKeysArray(): Type
 {
 return new NonEmptyArrayType();

src/Type/Accessory/HasOffsetValueType.php

@@ -195,6 +195,11 @@ public function unsetOffset(Type $offsetType): Type
 return $this;
 }
 
+public function getKeysArrayFiltered(Type $filterValueType, TrinaryLogic $strict): Type
+{
+return $this->getKeysArray();
+}
+
 public function getKeysArray(): Type
 {
 return new NonEmptyArrayType();

src/Type/Accessory/NonEmptyArrayType.php

@@ -159,6 +159,11 @@ public function unsetOffset(Type $offsetType): Type
 return new ErrorType();
 }
 
+public function getKeysArrayFiltered(Type $filterValueType, TrinaryLogic $strict): Type
+{
+return $this->getKeysArray();
+}
+
 public function getKeysArray(): Type
 {
 return $this;

src/Type/Accessory/OversizedArrayType.php

@@ -154,6 +154,11 @@ public function unsetOffset(Type $offsetType): Type
 return new ErrorType();
 }
 
+public function getKeysArrayFiltered(Type $filterValueType, TrinaryLogic $strict): Type
+{
+return $this->getKeysArray();
+}
+
 public function getKeysArray(): Type
 {
 return $this;

src/Type/ArrayType.php

@@ -170,6 +170,11 @@ public function generalizeValues(): self
 return new self($this->keyType, $this->itemType->generalize(GeneralizePrecision::lessSpecific()));
 }
 
+public function getKeysArrayFiltered(Type $filterValueType, TrinaryLogic $strict): Type
+{
+return $this->getKeysArray();
+}
+
 public function getKeysArray(): Type
 {
 return TypeCombinator::intersect(new self(new IntegerType(), $this->getIterableKeyType()), new AccessoryArrayListType());

src/Type/Constant/ConstantArrayType.php

@@ -35,6 +35,7 @@
 use PHPStan\Type\Generic\TemplateTypeMap;
 use PHPStan\Type\Generic\TemplateTypeVariance;
 use PHPStan\Type\IntegerRangeType;
+use PHPStan\Type\IntegerType;
 use PHPStan\Type\IntersectionType;
 use PHPStan\Type\IsSuperTypeOfResult;
 use PHPStan\Type\MixedType;
@@ -1372,6 +1373,19 @@ private function degradeToGeneralArray(): Type
 return $builder->getArray();
 }
 
+public function getKeysArrayFiltered(Type $filterValueType, TrinaryLogic $strict): Type
+{
+$keysArray = $this->getKeysOrValuesArray($this->keyTypes);
+
+return TypeCombinator::intersect(
+new ArrayType(
+new IntegerType(),
+$keysArray->getIterableValueType(),
+),
+new AccessoryArrayListType(),
+);
+}
+
 public function getKeysArray(): self
 {
 return $this->getKeysOrValuesArray($this->keyTypes);

src/Type/IntersectionType.php

@@ -842,6 +842,11 @@ public function unsetOffset(Type $offsetType): Type
 return $this->intersectTypes(static fn (Type $type): Type => $type->unsetOffset($offsetType));
 }
 
+public function getKeysArrayFiltered(Type $filterValueType, TrinaryLogic $strict): Type
+{
+return $this->intersectTypes(static fn (Type $type): Type => $type->getKeysArrayFiltered($filterValueType, $strict));
+}
+
 public function getKeysArray(): Type
 {
 return $this->intersectTypes(static fn (Type $type): Type => $type->getKeysArray());

src/Type/MixedType.php

@@ -180,6 +180,11 @@ public function unsetOffset(Type $offsetType): Type
 return $this;
 }
 
+public function getKeysArrayFiltered(Type $filterValueType, TrinaryLogic $strict): Type
+{
+return $this->getKeysArray();
+}
+
 public function getKeysArray(): Type
 {
 if ($this->isArray()->no()) {

src/Type/NeverType.php

@@ -273,6 +273,11 @@ public function unsetOffset(Type $offsetType): Type
 return new NeverType();
 }
 
+public function getKeysArrayFiltered(Type $filterValueType, TrinaryLogic $strict): Type
+{
+return $this->getKeysArray();
+}
+
 public function getKeysArray(): Type
 {
 return new NeverType();