phpstan · ondrejmirtes · Oct 11, 2022 · Oct 10, 2022
diff --git a/src/Type/Accessory/AccessoryArrayListType.php b/src/Type/Accessory/AccessoryArrayListType.php
@@ -152,6 +152,16 @@ public function getIterableKeyType(): Type
 		return IntegerRangeType::fromInterval(0, null);
 	}
 
+	public function getFirstIterableKeyType(): Type
+	{
+		return new ConstantIntegerType(0);
+	}
+
+	public function getLastIterableKeyType(): Type
+	{
+		return $this->getIterableKeyType();
+	}
+
 	public function getIterableValueType(): Type
 	{
 		return new MixedType();

diff --git a/src/Type/Accessory/NonEmptyArrayType.php b/src/Type/Accessory/NonEmptyArrayType.php
@@ -141,6 +141,16 @@ public function getIterableKeyType(): Type
 		return new MixedType();
 	}
 
+	public function getFirstIterableKeyType(): Type
+	{
+		return new MixedType();
+	}
+
+	public function getLastIterableKeyType(): Type
+	{
+		return new MixedType();
+	}
+
 	public function getIterableValueType(): Type
 	{
 		return new MixedType();

diff --git a/src/Type/Accessory/OversizedArrayType.php b/src/Type/Accessory/OversizedArrayType.php
@@ -140,6 +140,16 @@ public function getIterableKeyType(): Type
 		return new MixedType();
 	}
 
+	public function getFirstIterableKeyType(): Type
+	{
+		return new MixedType();
+	}
+
+	public function getLastIterableKeyType(): Type
+	{
+		return new MixedType();
+	}
+
 	public function getIterableValueType(): Type
 	{
 		return new MixedType();

diff --git a/src/Type/ArrayType.php b/src/Type/ArrayType.php
@@ -208,6 +208,16 @@ public function getIterableKeyType(): Type
 		return $keyType;
 	}
 
+	public function getFirstIterableKeyType(): Type
+	{
+		return $this->getIterableKeyType();
+	}
+
+	public function getLastIterableKeyType(): Type
+	{
+		return $this->getIterableKeyType();
+	}
+
 	public function getIterableValueType(): Type
 	{
 		return $this->getItemType();

diff --git a/src/Type/Constant/ConstantArrayType.php b/src/Type/Constant/ConstantArrayType.php
@@ -227,30 +227,16 @@ public function getKeyTypes(): array
 		return $this->keyTypes;
 	}
 
+	/** @deprecated Use getFirstIterableKeyType() instead */
 	public function getFirstKeyType(): Type
 	{
-		$keyTypes = [];
-		foreach ($this->keyTypes as $i => $keyType) {
-			$keyTypes[] = $keyType;
-			if (!$this->isOptionalKey($i)) {
-				break;
-			}
-		}
-
-		return TypeCombinator::union(...$keyTypes);
+		return $this->getFirstIterableKeyType();
 	}
 
+	/** @deprecated Use getLastIterableKeyType() instead */
 	public function getLastKeyType(): Type
 	{
-		$keyTypes = [];
-		for ($i = count($this->keyTypes) - 1; $i >= 0; $i--) {
-			$keyTypes[] = $this->keyTypes[$i];
-			if (!$this->isOptionalKey($i)) {
-				break;
-			}
-		}
-
-		return TypeCombinator::union(...$keyTypes);
+		return $this->getLastIterableKeyType();
 	}
 
 	/**
@@ -698,6 +684,32 @@ public function isIterableAtLeastOnce(): TrinaryLogic
 		return TrinaryLogic::createMaybe();
 	}
 
+	public function getFirstIterableKeyType(): Type
+	{
+		$keyTypes = [];
+		foreach ($this->keyTypes as $i => $keyType) {
+			$keyTypes[] = $keyType;
+			if (!$this->isOptionalKey($i)) {
+				break;
+			}
+		}
+
+		return TypeCombinator::union(...$keyTypes);
+	}
+
+	public function getLastIterableKeyType(): Type
+	{
+		$keyTypes = [];
+		for ($i = count($this->keyTypes) - 1; $i >= 0; $i--) {
+			$keyTypes[] = $this->keyTypes[$i];
+			if (!$this->isOptionalKey($i)) {
+				break;
+			}
+		}
+
+		return TypeCombinator::union(...$keyTypes);
+	}
+
 	public function getFirstIterableValueType(): Type
 	{
 		$valueTypes = [];

diff --git a/src/Type/IntersectionType.php b/src/Type/IntersectionType.php
@@ -411,6 +411,16 @@ public function getIterableKeyType(): Type
 		return $this->intersectTypes(static fn (Type $type): Type => $type->getIterableKeyType());
 	}
 
+	public function getFirstIterableKeyType(): Type
+	{
+		return $this->intersectTypes(static fn (Type $type): Type => $type->getFirstIterableKeyType());
+	}
+
+	public function getLastIterableKeyType(): Type
+	{
+		return $this->intersectTypes(static fn (Type $type): Type => $type->getLastIterableKeyType());
+	}
+
 	public function getIterableValueType(): Type
 	{
 		return $this->intersectTypes(static fn (Type $type): Type => $type->getIterableValueType());

diff --git a/src/Type/MixedType.php b/src/Type/MixedType.php
@@ -371,6 +371,16 @@ public function getIterableKeyType(): Type
 		return new self($this->isExplicitMixed);
 	}
 
+	public function getFirstIterableKeyType(): Type
+	{
+		return new self($this->isExplicitMixed);
+	}
+
+	public function getLastIterableKeyType(): Type
+	{
+		return new self($this->isExplicitMixed);
+	}
+
 	public function getIterableValueType(): Type
 	{
 		return new self($this->isExplicitMixed);

diff --git a/src/Type/Php/ArrayKeyFirstDynamicReturnTypeExtension.php b/src/Type/Php/ArrayKeyFirstDynamicReturnTypeExtension.php
@@ -5,13 +5,10 @@
 use PhpParser\Node\Expr\FuncCall;
 use PHPStan\Analyser\Scope;
 use PHPStan\Reflection\FunctionReflection;
-use PHPStan\Reflection\ParametersAcceptorSelector;
-use PHPStan\Type\Constant\ConstantIntegerType;
 use PHPStan\Type\DynamicFunctionReturnTypeExtension;
 use PHPStan\Type\NullType;
 use PHPStan\Type\Type;
 use PHPStan\Type\TypeCombinator;
-use function count;
 
 class ArrayKeyFirstDynamicReturnTypeExtension implements DynamicFunctionReturnTypeExtension
 {
@@ -21,10 +18,10 @@ public function isFunctionSupported(FunctionReflection $functionReflection): boo
 		return $functionReflection->getName() === 'array_key_first';
 	}
 
-	public function getTypeFromFunctionCall(FunctionReflection $functionReflection, FuncCall $functionCall, Scope $scope): Type
+	public function getTypeFromFunctionCall(FunctionReflection $functionReflection, FuncCall $functionCall, Scope $scope): ?Type
 	{
 		if (!isset($functionCall->getArgs()[0])) {
-			return ParametersAcceptorSelector::selectSingle($functionReflection->getVariants())->getReturnType();
+			return null;
 		}
 
 		$argType = $scope->getType($functionCall->getArgs()[0]->value);
@@ -33,30 +30,7 @@ public function getTypeFromFunctionCall(FunctionReflection $functionReflection,
 			return new NullType();
 		}
 
-		$constantArrays = $argType->getConstantArrays();
-		if (count($constantArrays) > 0) {
-			$keyTypes = [];
-			foreach ($constantArrays as $constantArray) {
-				$iterableAtLeastOnce = $constantArray->isIterableAtLeastOnce();
-				if (!$iterableAtLeastOnce->yes()) {
-					$keyTypes[] = new NullType();
-				}
-				if ($iterableAtLeastOnce->no()) {
-					continue;
-				}
-
-				$keyTypes[] = $constantArray->getFirstKeyType();
-			}
-
-			return TypeCombinator::union(...$keyTypes);
-		}
-
-		if ($argType->isList()->yes()) {
-			$keyType = new ConstantIntegerType(0);
-		} else {
-			$keyType = $argType->getIterableKeyType();
-		}
-
+		$keyType = $argType->getFirstIterableKeyType();
 		if ($iterableAtLeastOnce->yes()) {
 			return $keyType;
 		}

diff --git a/src/Type/Php/ArrayKeyLastDynamicReturnTypeExtension.php b/src/Type/Php/ArrayKeyLastDynamicReturnTypeExtension.php
@@ -5,12 +5,10 @@
 use PhpParser\Node\Expr\FuncCall;
 use PHPStan\Analyser\Scope;
 use PHPStan\Reflection\FunctionReflection;
-use PHPStan\Reflection\ParametersAcceptorSelector;
 use PHPStan\Type\DynamicFunctionReturnTypeExtension;
 use PHPStan\Type\NullType;
 use PHPStan\Type\Type;
 use PHPStan\Type\TypeCombinator;
-use function count;
 
 class ArrayKeyLastDynamicReturnTypeExtension implements DynamicFunctionReturnTypeExtension
 {
@@ -20,10 +18,10 @@ public function isFunctionSupported(FunctionReflection $functionReflection): boo
 		return $functionReflection->getName() === 'array_key_last';
 	}
 
-	public function getTypeFromFunctionCall(FunctionReflection $functionReflection, FuncCall $functionCall, Scope $scope): Type
+	public function getTypeFromFunctionCall(FunctionReflection $functionReflection, FuncCall $functionCall, Scope $scope): ?Type
 	{
 		if (!isset($functionCall->getArgs()[0])) {
-			return ParametersAcceptorSelector::selectSingle($functionReflection->getVariants())->getReturnType();
+			return null;
 		}
 
 		$argType = $scope->getType($functionCall->getArgs()[0]->value);
@@ -32,25 +30,7 @@ public function getTypeFromFunctionCall(FunctionReflection $functionReflection,
 			return new NullType();
 		}
 
-		$constantArrays = $argType->getConstantArrays();
-		if (count($constantArrays) > 0) {
-			$keyTypes = [];
-			foreach ($constantArrays as $constantArray) {
-				$iterableAtLeastOnce = $constantArray->isIterableAtLeastOnce();
-				if (!$iterableAtLeastOnce->yes()) {
-					$keyTypes[] = new NullType();
-				}
-				if ($iterableAtLeastOnce->no()) {
-					continue;
-				}
-
-				$keyTypes[] = $constantArray->getLastKeyType();
-			}
-
-			return TypeCombinator::union(...$keyTypes);
-		}
-
-		$keyType = $argType->getIterableKeyType();
+		$keyType = $argType->getLastIterableKeyType();
 		if ($iterableAtLeastOnce->yes()) {
 			return $keyType;
 		}

diff --git a/src/Type/StaticType.php b/src/Type/StaticType.php
@@ -302,6 +302,16 @@ public function getIterableKeyType(): Type
 		return $this->getStaticObjectType()->getIterableKeyType();
 	}
 
+	public function getFirstIterableKeyType(): Type
+	{
+		return $this->getStaticObjectType()->getFirstIterableKeyType();
+	}
+
+	public function getLastIterableKeyType(): Type
+	{
+		return $this->getStaticObjectType()->getLastIterableKeyType();
+	}
+
 	public function getIterableValueType(): Type
 	{
 		return $this->getStaticObjectType()->getIterableValueType();

diff --git a/src/Type/Traits/LateResolvableTypeTrait.php b/src/Type/Traits/LateResolvableTypeTrait.php
@@ -130,6 +130,16 @@ public function getIterableKeyType(): Type
 		return $this->resolve()->getIterableKeyType();
 	}
 
+	public function getFirstIterableKeyType(): Type
+	{
+		return $this->resolve()->getFirstIterableKeyType();
+	}
+
+	public function getLastIterableKeyType(): Type
+	{
+		return $this->resolve()->getLastIterableKeyType();
+	}
+
 	public function getIterableValueType(): Type
 	{
 		return $this->resolve()->getIterableValueType();

diff --git a/src/Type/Traits/MaybeArrayTypeTrait.php b/src/Type/Traits/MaybeArrayTypeTrait.php
@@ -19,6 +19,16 @@ public function getConstantArrays(): array
 		return [];
 	}
 
+	public function getFirstIterableKeyType(): Type
+	{
+		return new MixedType();
+	}
+
+	public function getLastIterableKeyType(): Type
+	{
+		return new MixedType();
+	}
+
 	public function getFirstIterableValueType(): Type
 	{
 		return new MixedType();

diff --git a/src/Type/Traits/NonArrayTypeTrait.php b/src/Type/Traits/NonArrayTypeTrait.php
@@ -19,6 +19,16 @@ public function getConstantArrays(): array
 		return [];
 	}
 
+	public function getFirstIterableKeyType(): Type
+	{
+		return new ErrorType();
+	}
+
+	public function getLastIterableKeyType(): Type
+	{
+		return new ErrorType();
+	}
+
 	public function getFirstIterableValueType(): Type
 	{
 		return new ErrorType();

diff --git a/src/Type/Type.php b/src/Type/Type.php
@@ -66,6 +66,10 @@ public function isIterableAtLeastOnce(): TrinaryLogic;
 
 	public function getIterableKeyType(): Type;
 
+	public function getFirstIterableKeyType(): Type;
+
+	public function getLastIterableKeyType(): Type;
+
 	public function getIterableValueType(): Type;
 
 	public function getFirstIterableValueType(): Type;

diff --git a/src/Type/UnionType.php b/src/Type/UnionType.php
@@ -425,6 +425,16 @@ public function getIterableKeyType(): Type
 		return $this->unionTypes(static fn (Type $type): Type => $type->getIterableKeyType());
 	}
 
+	public function getFirstIterableKeyType(): Type
+	{
+		return $this->unionTypes(static fn (Type $type): Type => $type->getFirstIterableKeyType());
+	}
+
+	public function getLastIterableKeyType(): Type
+	{
+		return $this->unionTypes(static fn (Type $type): Type => $type->getLastIterableKeyType());
+	}
+
 	public function getIterableValueType(): Type
 	{
 		return $this->unionTypes(static fn (Type $type): Type => $type->getIterableValueType());