Optimize match expression with many conditions

Author: ondrejmirtes

src/Analyser/MutatingScope.php

@@ -1490,16 +1490,21 @@ private function resolveType(string $exprString, Expr $node): Type
 					throw new ShouldNotHappenException();
 				}
 
-				$filteringExpr = null;
-				foreach ($arm->conds as $armCond) {
-					$armCondExpr = new BinaryOp\Identical($cond, $armCond);
-
-					if ($filteringExpr === null) {
-						$filteringExpr = $armCondExpr;
-						continue;
+				if (count($arm->conds) === 1) {
+					$filteringExpr = new BinaryOp\Identical($cond, $arm->conds[0]);
+				} else {
+					$items = [];
+					foreach ($arm->conds as $filteringExpr) {
+						$items[] = new Expr\ArrayItem($filteringExpr);
 					}
-
-					$filteringExpr = new BinaryOp\BooleanOr($filteringExpr, $armCondExpr);
+					$filteringExpr = new FuncCall(
+						new Name\FullyQualified('in_array'),
+						[
+							new Arg($cond),
+							new Arg(new Array_($items)),
+							new Arg(new ConstFetch(new Name\FullyQualified('true'))),
+						],
+					);
 				}
 
 				$filteringExprType = $matchScope->getType($filteringExpr);

src/Analyser/NodeScopeResolver.php

@@ -2849,7 +2849,7 @@ static function (Node $node, Scope $scope) use ($nodeCallback): void {
 					throw new ShouldNotHappenException();
 				}
 
-				$filteringExpr = null;
+				$filteringExprs = [];
 				$armCondScope = $matchScope;
 				$condNodes = [];
 				foreach ($arm->conds as $armCond) {
@@ -2864,12 +2864,24 @@ static function (Node $node, Scope $scope) use ($nodeCallback): void {
 						$hasAlwaysTrueCond = true;
 					}
 					$armCondScope = $armCondResult->getScope()->filterByFalseyValue($armCondExpr);
-					if ($filteringExpr === null) {
-						$filteringExpr = $armCondExpr;
-						continue;
-					}
+					$filteringExprs[] = $armCond;
+				}
 
-					$filteringExpr = new BinaryOp\BooleanOr($filteringExpr, $armCondExpr);
+				if (count($filteringExprs) === 1) {
+					$filteringExpr = new BinaryOp\Identical($expr->cond, $filteringExprs[0]);
+				} else {
+					$items = [];
+					foreach ($filteringExprs as $filteringExpr) {
+						$items[] = new ArrayItem($filteringExpr);
+					}
+					$filteringExpr = new FuncCall(
+						new Name\FullyQualified('in_array'),
+						[
+							new Arg($expr->cond),
+							new Arg(new Array_($items)),
+							new Arg(new ConstFetch(new Name\FullyQualified('true'))),
+						],
+					);
 				}
 
 				$bodyScope = $matchScope->filterByTruthyValue($filteringExpr);

src/Type/Php/InArrayFunctionTypeSpecifyingExtension.php

@@ -8,6 +8,7 @@
 use PHPStan\Analyser\TypeSpecifier;
 use PHPStan\Analyser\TypeSpecifierAwareExtension;
 use PHPStan\Analyser\TypeSpecifierContext;
+use PHPStan\Node\Expr\AlwaysRememberedExpr;
 use PHPStan\Reflection\FunctionReflection;
 use PHPStan\Type\Accessory\NonEmptyArrayType;
 use PHPStan\Type\ArrayType;
@@ -47,7 +48,8 @@ public function specifyTypes(FunctionReflection $functionReflection, FuncCall $n
 			return new SpecifiedTypes();
 		}
 
-		$needleType = $scope->getType($node->getArgs()[0]->value);
+		$needleExpr = $node->getArgs()[0]->value;
+		$needleType = $scope->getType($needleExpr);
 		$arrayType = $scope->getType($node->getArgs()[1]->value);
 		$arrayValueType = $arrayType->getIterableValueType();
 		$isStrictComparison = $isStrictComparison
@@ -71,12 +73,21 @@ public function specifyTypes(FunctionReflection $functionReflection, FuncCall $n
 			)
 		) {
 			$specifiedTypes = $this->typeSpecifier->create(
-				$node->getArgs()[0]->value,
+				$needleExpr,
 				$arrayValueType,
 				$context,
 				false,
 				$scope,
 			);
+			if ($needleExpr instanceof AlwaysRememberedExpr) {
+				$specifiedTypes = $specifiedTypes->unionWith($this->typeSpecifier->create(
+					$needleExpr->getExpr(),
+					$arrayValueType,
+					$context,
+					false,
+					$scope,
+				));
+			}
 		}
 
 		if (