Fix calling getVariableType without checking hasVariableType first

Author: ondrejmirtes

src/Analyser/MutatingScope.php

@@ -2010,11 +2010,21 @@ static function (Node $node, Scope $scope) use ($arrowScope, &$arrowFunctionImpu
 
 			$nameType = $this->getType($node->name);
 			if (count($nameType->getConstantStrings()) > 0) {
-				return TypeCombinator::union(
-					...array_map(fn ($constantString) => $this
-						->filterByTruthyValue(new BinaryOp\Identical($node->name, new String_($constantString->getValue())))
-						->getVariableType($constantString->getValue()), $nameType->getConstantStrings()),
-				);
+				$types = [];
+				foreach ($nameType->getConstantStrings() as $constantString) {
+					$variableScope = $this
+						->filterByTruthyValue(
+							new BinaryOp\Identical($node->name, new String_($constantString->getValue())),
+						);
+					if ($variableScope->hasVariableType($constantString->getValue())->no()) {
+						$types[] = new ErrorType();
+						continue;
+					}
+
+					$types[] = $variableScope->getVariableType($constantString->getValue());
+				}
+
+				return TypeCombinator::union(...$types);
 			}
 		}
 

tests/PHPStan/Analyser/AnalyserIntegrationTest.php

@@ -896,6 +896,16 @@ public function testBug7500(): void
 		$this->assertNoErrors($errors);
 	}
 
+	public function testBug12767(): void
+	{
+		$errors = $this->runAnalyse(__DIR__ . '/data/bug-12767.php');
+		$this->assertCount(3, $errors);
+
+		$this->assertSame('Expected type int, actual: *ERROR*', $errors[0]->getMessage());
+		$this->assertSame('Undefined variable: $field1', $errors[1]->getMessage());
+		$this->assertSame('Undefined variable: $field2', $errors[2]->getMessage());
+	}
+
 	public function testBug7554(): void
 	{
 		$errors = $this->runAnalyse(__DIR__ . '/data/bug-7554.php');

tests/PHPStan/Analyser/data/bug-12767.php

@@ -0,0 +1,19 @@
+<?php
+
+namespace Bug12767;
+
+use function PHPStan\Testing\assertType;
+
+class SkipDynamicVariable
+{
+	public function bar(): void
+	{
+		$employee = (object) ['data' => ['dd1' => 1, 'dd2' => 2]];
+
+		for ($i=1; $i <= 2; $i++) {
+			${'field'.$i} = $employee->data['dd'.$i];
+
+			assertType('int', ${'field'.$i});
+		}
+	}
+}