Fix too early inference

Author: VincentLanglet

src/Analyser/MutatingScope.php

@@ -1129,9 +1129,6 @@ private function resolveType(string $exprString, Expr $node): Type
 }
 
 $resultType = $this->initializerExprTypeResolver->resolveConcatType($resultType, $partType);
-if (count($resultType->getConstantStrings()) === 0) {
-return $resultType;
-}
 }
 
 return $resultType ?? new ConstantStringType('');

tests/PHPStan/Rules/Comparison/MatchExpressionRuleTest.php

@@ -599,4 +599,13 @@ public function testBug9436(): void
 $this->analyse([__DIR__ . '/data/bug-9436.php'], []);
 }
 
+public function testBug11852(): void
+{
+if (PHP_VERSION_ID < 80000) {
+$this->markTestSkipped('Test requires PHP 8.0.');
+}
+
+$this->analyse([__DIR__ . '/data/bug-11852.php'], []);
+}
+
 }

tests/PHPStan/Rules/Comparison/data/bug-11852.php

@@ -0,0 +1,13 @@
+<?php // lint >= 8.0
+
+namespace Bug11852;
+
+function sayHello(int $type, string $activity): int
+{
+return match("$type:$activity") {
+'159:Work' => 12,
+'159:education' => 19,
+
+default => throw new \InvalidArgumentException("unknown values $type:$activity"),
+};
+}