Ignore a lower bound that refers to the inferred template argument itself

src/Analyser/Generics/TemplateArgumentSolver.php

@@ -131,6 +131,18 @@ private function removeSelfBounds(Type $type, string $key): Type
 		return $type;
 	}
 
+	private function refersToKey(Type $type, string $key): bool
+	{
+		$refers = false;
+		TypeTraverser::map($type, function (Type $type, callable $traverse) use ($key, &$refers): Type {
+			if ($type instanceof UnresolvedTemplateArgumentType && $this->representative(self::key($type->getSite(), $type->getTemplateName())) === $key) {
+				$refers = true;
+			}
+			return $refers ? $type : $traverse($type);
+		});
+		return $refers;
+	}
+
 	/** @var array<string, true> */
 	private array $resolving = [];
 
@@ -207,7 +219,14 @@ private function resolveObservation(array $observation): Type
 		$initial = $observation['initial'] !== null ? $this->substituteResolutions($observation['initial']) : null;
 		$template = $observation['marker']->getTemplate();
 		$lowerBounds = [];
+		$key = $this->representative(self::key($observation['marker']->getSite(), $observation['marker']->getTemplateName()));
 		foreach ($observation['lowerBounds'] as $lowerBound) {
+			if ($this->refersToKey($lowerBound, $key)) {
+				// the object passed to its own method ($map->set($map) with
+				// set(TOwner $owner)) can only be bounded by itself - it says
+				// nothing about the argument
+				continue;
+			}
 			$inferred = $template->inferTemplateTypes($this->substituteResolutions($lowerBound))->getType($template->getName());
 			if ($inferred === null) {
 				continue;

tests/PHPStan/Rules/Methods/CallMethodsRuleTest.php

@@ -4560,6 +4560,14 @@ public function testBug15251(): void
 		$this->analyse([__DIR__ . '/data/bug-15251.php'], []);
 	}
 
+	public function testBug15434(): void
+	{
+		$this->checkThisOnly = false;
+		$this->checkNullables = true;
+		$this->checkUnionTypes = true;
+		$this->analyse([__DIR__ . '/data/bug-15434.php'], []);
+	}
+
 	#[RequiresPhp('>= 8.1.0')]
 	public function testClassConstantWildcardArguments(): void
 	{

tests/PHPStan/Rules/Methods/data/bug-15434.php

@@ -0,0 +1,23 @@
+<?php declare(strict_types = 1);
+
+namespace Bug15434;
+
+class Test
+{
+    public function testSet(): void
+    {
+        $map = new WeakAnalysingMap();
+        $map->set($map);
+	}
+}
+
+/**
+ * @template TOwner of object
+ */
+class WeakAnalysingMap
+{
+    /**
+     * @param TOwner $owner
+     */
+    public function set(object $owner): void {}
+}