Fix phpstan/phpstan#7718: "Variable might not be defined" in second identical if block

src/Analyser/TypeSpecifier.php

@@ -2605,9 +2605,19 @@
 		$leftTypes = $this->create($expr->left, $leftType, $context, $scope)->setRootExpr($expr);
 		$rightTypes = $this->create($expr->right, $rightType, $context, $scope)->setRootExpr($expr);
 
-		return $context->true()
+		$result = $context->true()
 			? $leftTypes->unionWith($rightTypes)
 			: $leftTypes->normalize($scope)->intersectWith($rightTypes->normalize($scope));
+
+		if (
+			!$context->null()
+			&& ($leftTypes->getSureTypes() !== [] || $leftTypes->getSureNotTypes() !== [])
+			&& ($rightTypes->getSureTypes() !== [] || $rightTypes->getSureNotTypes() !== [])
+		) {
+			$result = $result->unionWith($this->handleDefaultTruthyOrFalseyContext($context, $expr, $scope));
+		}
+
+		return $result;
 	}
 
 	public function resolveIdentical(Expr\BinaryOp\Identical $expr, Scope $scope, TypeSpecifierContext $context): SpecifiedTypes

tests/PHPStan/Analyser/TypeSpecifierTest.php

@@ -1317,6 +1317,7 @@ public static function dataCondition(): iterable
 				[
 					'$float' => 'float',
 					'(int) $float' => 'int',
+					'$float == (int) $float' => '~0|0.0|\'\'|\'0\'|array{}|false|null',
 				],
 				[],
 			],

tests/PHPStan/Rules/Variables/DefinedVariableRuleTest.php

@@ -1514,4 +1514,13 @@ public function testBug14117(): void
 		]);
 	}
 
+	public function testBug7718(): void
+	{
+		$this->cliArgumentsVariablesRegistered = true;
+		$this->polluteScopeWithLoopInitialAssignments = false;
+		$this->checkMaybeUndefinedVariables = true;
+		$this->polluteScopeWithAlwaysIterableForeach = true;
+		$this->analyse([__DIR__ . '/data/bug-7718.php'], []);
+	}
+
 }

tests/PHPStan/Rules/Variables/data/bug-7718.php

@@ -0,0 +1,11 @@
+<?php
+
+namespace Bug7718;
+
+if ($_GET['something'] == 'banana'){
+	$bananas = 1;
+}
+
+if ($_GET['something'] == 'banana'){
+	echo $bananas;
+}