mapPsrPaths example

'Unable to register plugin "%s" in autoload. Required property `psr-4` or `psr-0` missing in property autoload.',
                    $plugin['baseClass']
                );

                throw new KernelPluginLoaderException($pluginName, $reason);
            }

            foreach ($psr4 as $namespace => $paths) {
                if (\is_string($paths)) {
                    $paths = [$paths];
                }
                $mappedPaths = $this->mapPsrPaths($pluginName, $paths, $projectDir, $plugin['path']);
                $this->classLoader->addPsr4($namespace, $mappedPaths);
                if ($this->classLoader->isClassMapAuthoritative()) {
                    $this->classLoader->setClassMapAuthoritative(false);
                }
            }

            foreach ($psr0 as $namespace => $paths) {
                if (\is_string($paths)) {
                    $paths = [$paths];
                }
                $mappedPaths = $this->mapPsrPaths($pluginName, $paths, $projectDir, $plugin['path']);