Devuelve extension

@return string
541038
public function getExtension(): ?string
    {
        $exentension = pathinfo($this->path, PATHINFO_EXTENSION);

        if (is_blank($exentension)) {
            return null;
        };

        return $exentension;
    }
93067
protected function createOwnExtension()
    {
        $this->ownExtension = function (XType $type, $value, $view, $lang) {
            return $this->selfFormat($type, $value, $view, $lang);
        };
    }
1201925
protected function _getExtendOptionsPaginationUrl() {
		$options = [];
		$ext = (string)$this->request->param('ext');
		$ext = mb_strtolower($ext);
		if (empty($ext) || ($ext !== 'prt')) {
			return $options;
		}

		$options = compact('ext');

		return $options;
	}
1162757
public function getAvailableExtensions(): Extensions
    {
        if ($this->availableExtensions instanceof Extensions) {
            return $this->availableExtensions;
        }
        $foundExtensions  = $this->filesystemFinder->findExtensions();
        $storedExtensions = app('antares.installed') ? $this->extensionsRepository->all() : new Collection();

        foreach ($foundExtensions as $foundExtension) {
            $extension = $storedExtensions->first(function(ExtensionModel $extensionModel) use($foundExtension) {
                return $extensionModel->getFullName() === $foundExtension->getPackage()->getName();
            });

            $configFile = $foundExtension->getPath() . '/resources/config/settings.php';

            if ($this->filesystem->exists($configFile)) {
                $foundExtension->setSettings($this->settingsFactory->createFromConfig($configFile));
            }

            if ($extension instanceof ExtensionModel) {
                $foundExtension->setStatus($extension->getStatus());
                $foundExtension->setIsRequired($extension->isRequired());
                $foundExtension->getSettings()->updateData($extension->getOptions());
            }
        }

        return $this->availableExtensions = $foundExtensions;
    }
307530
public function getExtensionsInfoList()
    {
        $data = json_decode(
            $this->getRemoteContents($this->extensionsInfofoUrl)
        );

        $content = $data->encoding === 'base64' ? base64_decode($data->content) : [];
        return json_decode($content, true);// true to array
    }
1152898
public function getEnabledExtensions()
    {
        $enabled = [];
        $extensions = $this->getExtensions();

        foreach ($this->getEnabled() as $id) {
            if (isset($extensions[$id])) {
                $enabled[$id] = $extensions[$id];
            }
        }

        return $enabled;
    }
664713
public function getInstalledExtensions()
    {
        $returnValue = array();
        foreach ($this->getInstalledExtensionsIds() as $extId) {
            $returnValue[$extId] = $this->getExtensionById($extId);
        }
        return $returnValue;
    }
717241
private function determineExtension()
    {
        $ext = 'php';
        if (in_array($this->driverClass, $this->extensionToDriver)) {
            $map = array_flip($this->extensionToDriver);
            $ext = $map[$this->driverClass];
        }
        return $ext;
    }
1086577
public function getExtension()
    {
        $pos = strrpos($this->name, '.');
        if ($pos === false) {
            return null;
        } else {
            return substr($this->name, $pos + 1);
        }
    }
779165
public function urlExtension()
    {
        if ($this->home()) {
            return '';
        }

        // if not set in the page get the value from system config
        if (null === $this->url_extension) {
            $this->url_extension = Grav::instance()['config']->get('system.pages.append_url_extension', '');
        }

        return $this->url_extension;
    }
370228
public function getExtensionModel()
    {
        if ($this->extensionModel === null) {
            $this->load->model('extension/extension');
            /** @noinspection PhpUndefinedFieldInspection */
            $this->extensionModel = $this->model_extension_extension;
        }
        return $this->extensionModel;
    }
963312
public function getExtension(bool $withDot = false): string
    {
        if (null === $this->extension) {
            $this->setPathInfo();
        }

        return ($withDot ? '.' : '') . $this->extension;
    }
1109981
public function ext()
    {
        if (!$this->info) {
            $this->info();
        }
        if (isset($this->info['extension'])) {
            return $this->info['extension'];
        }

        return false;
    }
835275
public function getExtension()
  {
    $f = $this->getValue();

    if ($f) {
      return $f instanceof UploadedFile ? $f->getClientOriginalExtension() : $f->getExtension();
    }

    return false;
  }
240393
public function getExtensionsByType()
  {
    $ext = array();

    foreach ($this->Config->get('file-extensions') as $key => $value)
    {
      $ext[$key] = $value['extensions'];
    }

    return $ext;
  }
1208408
public function resolveExtension()
    {
        if (($pos = strrpos($this->path, '.')) !== false) {
            return substr($this->path, $pos + 1);
        }

        return '';
    }
872214
public function addExtension($extension = null)
    {
        if ($extension == null) {
            return $this->twigEnvironment->addExtension($this->twigDebug());
        }

        return $this->twigEnvironment->addExtension($extension);
    }