Use case insensitive matching to detect usages of private methods

Author: stof

src/Rules/DeadCode/UnusedPrivateMethodRule.php

@@ -56,7 +56,7 @@ public function processNode(Node $node, Scope $scope): array
 			if (strtolower($methodName) === '__clone') {
 				continue;
 			}
-			$methods[$methodName] = $method;
+			$methods[strtolower($methodName)] = $method;
 		}
 
 		$arrayCalls = [];
@@ -105,7 +105,7 @@ public function processNode(Node $node, Scope $scope): array
 				if ($inMethod->getName() === $methodName) {
 					continue;
 				}
-				unset($methods[$methodName]);
+				unset($methods[strtolower($methodName)]);
 			}
 		}
 
@@ -144,26 +144,27 @@ public function processNode(Node $node, Scope $scope): array
 						if ($inMethod->getName() === $typeAndMethod->getMethod()) {
 							continue;
 						}
-						unset($methods[$typeAndMethod->getMethod()]);
+						unset($methods[strtolower($typeAndMethod->getMethod())]);
 					}
 				}
 			}
 		}
 
 		$errors = [];
-		foreach ($methods as $methodName => $method) {
+		foreach ($methods as $method) {
+			$originalMethodName = $method->getNode()->name->toString();
 			$methodType = 'Method';
 			if ($method->getNode()->isStatic()) {
 				$methodType = 'Static method';
 			}
-			$errors[] = RuleErrorBuilder::message(sprintf('%s %s::%s() is unused.', $methodType, $classReflection->getDisplayName(), $methodName))
+			$errors[] = RuleErrorBuilder::message(sprintf('%s %s::%s() is unused.', $methodType, $classReflection->getDisplayName(), $originalMethodName))
 				->line($method->getNode()->getLine())
 				->identifier('deadCode.unusedMethod')
 				->metadata([
 					'classOrder' => $node->getClass()->getAttribute('statementOrder'),
 					'classDepth' => $node->getClass()->getAttribute('statementDepth'),
 					'classStartLine' => $node->getClass()->getStartLine(),
-					'methodName' => $methodName,
+					'methodName' => $originalMethodName,
 				])
 				->build();
 		}

tests/PHPStan/Rules/DeadCode/UnusedPrivateMethodRuleTest.php

@@ -90,6 +90,11 @@ public function testBug7389(): void
 		]);
 	}
 
+	public function testBug8346(): void
+	{
+		$this->analyse([__DIR__ . '/data/bug-8346.php'], []);
+	}
+
 	public function testFalsePositiveWithTraitUse(): void
 	{
 		if (PHP_VERSION_ID < 80100) {

tests/PHPStan/Rules/DeadCode/data/bug-8346.php

@@ -0,0 +1,16 @@
+<?php
+
+namespace Bug8346;
+
+class HelloWorld
+{
+	public function speak(): string
+	{
+		return $this->sayhello('world');
+	}
+
+	private function sayHello(string $name): string
+	{
+		return 'Hello ' . $name;
+	}
+}