Passed
Push — master ( b39532...0bfe7e )
by Thomas
03:09
created

DeferBackend::javascript()   B

Complexity

Conditions 11
Paths 60

Size

Total Lines 29
Code Lines 17

Duplication

Lines 0
Ratio 0 %

Importance

Changes 7
Bugs 0 Features 0
Metric Value
eloc 17
c 7
b 0
f 0
dl 0
loc 29
rs 7.3166
cc 11
nc 60
nop 2

How to fix   Complexity   

Long Method

Small methods make your code easier to understand, in particular if combined with a good name. Besides, if your method is small, finding a good name is usually much easier.

For example, if you find yourself adding comments to a method's body, this is usually a good sign to extract the commented part to a new method, and use the comment as a starting point when coming up with a good name for this new method.

Commonly applied refactorings include:

1
<?php
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namespace LeKoala\DeferBackend;
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use Exception;
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use SilverStripe\View\HTML;
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use InvalidArgumentException;
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use SilverStripe\Core\Config\Configurable;
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use SilverStripe\View\SSViewer;
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use SilverStripe\View\Requirements;
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use SilverStripe\View\ThemeResourceLoader;
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use SilverStripe\View\Requirements_Backend;
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/**
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 * A backend that defers everything by default
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 *
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 * Also insert custom head tags first because order may matter
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 *
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 * @link https://flaviocopes.com/javascript-async-defer/
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 */
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class DeferBackend extends Requirements_Backend
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{
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    use Configurable;
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    /**
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     * @config
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     * @var boolean
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     */
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    private static $enable_js_modules = false;
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    // It's better to write to the head with defer
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    public $writeJavascriptToBody = false;
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    /**
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     * @return $this
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     */
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    public static function getDeferBackend()
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    {
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        $backend = Requirements::backend();
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        if (!$backend instanceof self) {
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            throw new Exception("Requirements backend is currently of class " . get_class($backend));
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        }
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        return $backend;
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    }
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    /**
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     * @param Requirements_Backend $oldBackend defaults to current backend
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     * @return $this
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     */
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    public static function replaceBackend(Requirements_Backend $oldBackend = null)
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    {
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        if ($oldBackend === null) {
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            $oldBackend = Requirements::backend();
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        }
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        $deferBackend = new static;
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        foreach ($oldBackend->getCSS() as $file => $opts) {
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            $deferBackend->css($file, null, $opts);
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        }
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        foreach ($oldBackend->getJavascript() as $file => $opts) {
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            $deferBackend->javascript($file, null, $opts);
0 ignored issues
show
Unused Code introduced by
The call to LeKoala\DeferBackend\DeferBackend::javascript() has too many arguments starting with $opts. ( Ignorable by Annotation )

If this is a false-positive, you can also ignore this issue in your code via the ignore-call  annotation

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            $deferBackend->/** @scrutinizer ignore-call */ 
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                           javascript($file, null, $opts);

This check compares calls to functions or methods with their respective definitions. If the call has more arguments than are defined, it raises an issue.

If a function is defined several times with a different number of parameters, the check may pick up the wrong definition and report false positives. One codebase where this has been known to happen is Wordpress. Please note the @ignore annotation hint above.

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        }
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        foreach ($oldBackend->getCustomCSS() as $id => $script) {
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            $deferBackend->customCSS($script, $id);
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        }
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        foreach ($oldBackend->getCustomScripts() as $id => $script) {
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            $deferBackend->customScript($script, $id);
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        }
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        Requirements::set_backend($deferBackend);
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        return $deferBackend;
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    }
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    /**
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     * @return array
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     */
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    public static function listCookieTypes()
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    {
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        return ['strictly-necessary', 'functionality', 'tracking', 'targeting'];
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    }
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    /**
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     * Register the given JavaScript file as required.
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     *
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     * @param string $file Either relative to docroot or in the form "vendor/package:resource"
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     * @param array $options List of options. Available options include:
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     * - 'provides' : List of scripts files included in this file
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     * - 'async' : Boolean value to set async attribute to script tag
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     * - 'defer' : Boolean value to set defer attribute to script tag (true by default)
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     * - 'type' : Override script type= value.
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     * - 'integrity' : SubResource Integrity hash
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     * - 'crossorigin' : Cross-origin policy for the resource
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     * - 'cookie-consent' : Type of cookie for conditionnal loading : strictly-necessary,functionality,tracking,targeting
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     */
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    public function javascript($file, $options = array())
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    {
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        if (!is_array($options)) {
0 ignored issues
show
introduced by
The condition is_array($options) is always true.
Loading history...
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            $options = [];
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        }
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        if (self::config()->enable_js_modules) {
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            if (empty($options['type']) && self::config()->enable_js_modules) {
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                $options['type'] = 'module';
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            }
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            // Modules are deferred by default
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            if (isset($options['defer']) && $options['type'] == "module") {
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                unset($options['defer']);
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            }
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        } else {
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            // We want to defer by default, but we can disable it if needed
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            if (!isset($options['defer'])) {
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                $options['defer'] = true;
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            }
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        }
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        if (isset($options['cookie-consent'])) {
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            if (!in_array($options['cookie-consent'], self::listCookieTypes())) {
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                throw new InvalidArgumentException("The cookie-consent value is invalid, it must be one of: strictly-necessary,functionality,tracking,targeting");
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            }
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            // switch to text plain for conditional loading
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            $options['type'] = 'text/plain';
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        }
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        parent::javascript($file, $options);
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        if (isset($options['cookie-consent'])) {
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            $this->javascript[$file]['cookie-consent'] = $options['cookie-consent'];
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        }
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    }
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    /**
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     * @param string $name
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     * @param string|array $type Pass the type or an array of options
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     * @return void
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     */
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    public function themedJavascript($name, $type = null)
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    {
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        $path = ThemeResourceLoader::inst()->findThemedJavascript($name, SSViewer::get_themes());
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        if ($path) {
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            $options = [];
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            if ($type) {
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                if (is_string($type)) {
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                    $options['type'] = $type;
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                } elseif (is_array($type)) {
0 ignored issues
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introduced by
The condition is_array($type) is always true.
Loading history...
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                    $options = $type;
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                }
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            }
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            $this->javascript($path, $options);
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        } else {
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            throw new InvalidArgumentException(
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                "The javascript file doesn't exist. Please check if the file $name.js exists in any "
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                    . "context or search for themedJavascript references calling this file in your templates."
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            );
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        }
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    }
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    /**
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     * Get all css files
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     *
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     * @return array
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     */
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    public function getCSS()
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    {
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        $css = array_diff_key($this->css, $this->blocked);
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        // Theme and assets files should always come last to have a proper cascade
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        $allCss = [];
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        $themeCss = [];
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        foreach ($css as $file => $arr) {
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            if (strpos($file, 'themes') === 0 || strpos($file, '/assets') === 0) {
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                $themeCss[$file] = $arr;
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            } else {
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                $allCss[$file] = $arr;
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            }
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        }
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        return array_merge($allCss, $themeCss);
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    }
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    /**
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     * Update the given HTML content with the appropriate include tags for the registered
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     * requirements. Needs to receive a valid HTML/XHTML template in the $content parameter,
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     * including a head and body tag.
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     *
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     * @param string $content HTML content that has already been parsed from the $templateFile through {@link SSViewer}
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     * @return string HTML content augmented with the requirements tags
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     */
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    public function includeInHTML($content)
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    {
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        // Get our CSP nonce, it's always good to have even if we don't use it :-)
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        $nonce = CspProvider::getCspNonce();
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        // Skip if content isn't injectable, or there is nothing to inject
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        $tagsAvailable = preg_match('#</head\b#', $content);
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        $hasFiles = $this->css || $this->javascript || $this->customCSS || $this->customScript || $this->customHeadTags;
0 ignored issues
show
Bug Best Practice introduced by
The expression $this->css of type array is implicitly converted to a boolean; are you sure this is intended? If so, consider using ! empty($expr) instead to make it clear that you intend to check for an array without elements.

This check marks implicit conversions of arrays to boolean values in a comparison. While in PHP an empty array is considered to be equal (but not identical) to false, this is not always apparent.

Consider making the comparison explicit by using empty(..) or ! empty(...) instead.

Loading history...
Bug Best Practice introduced by
The expression $this->customCSS of type array is implicitly converted to a boolean; are you sure this is intended? If so, consider using ! empty($expr) instead to make it clear that you intend to check for an array without elements.

This check marks implicit conversions of arrays to boolean values in a comparison. While in PHP an empty array is considered to be equal (but not identical) to false, this is not always apparent.

Consider making the comparison explicit by using empty(..) or ! empty(...) instead.

Loading history...
Bug Best Practice introduced by
The expression $this->customScript of type array is implicitly converted to a boolean; are you sure this is intended? If so, consider using ! empty($expr) instead to make it clear that you intend to check for an array without elements.

This check marks implicit conversions of arrays to boolean values in a comparison. While in PHP an empty array is considered to be equal (but not identical) to false, this is not always apparent.

Consider making the comparison explicit by using empty(..) or ! empty(...) instead.

Loading history...
Bug Best Practice introduced by
The expression $this->customHeadTags of type array is implicitly converted to a boolean; are you sure this is intended? If so, consider using ! empty($expr) instead to make it clear that you intend to check for an array without elements.

This check marks implicit conversions of arrays to boolean values in a comparison. While in PHP an empty array is considered to be equal (but not identical) to false, this is not always apparent.

Consider making the comparison explicit by using empty(..) or ! empty(...) instead.

Loading history...
Bug Best Practice introduced by
The expression $this->javascript of type array is implicitly converted to a boolean; are you sure this is intended? If so, consider using ! empty($expr) instead to make it clear that you intend to check for an array without elements.

This check marks implicit conversions of arrays to boolean values in a comparison. While in PHP an empty array is considered to be equal (but not identical) to false, this is not always apparent.

Consider making the comparison explicit by using empty(..) or ! empty(...) instead.

Loading history...
188
        if (!$tagsAvailable || !$hasFiles) {
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            return $content;
190
        }
191
        $requirements = '';
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        $jsRequirements = '';
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        // Combine files - updates $this->javascript and $this->css
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        $this->processCombinedFiles();
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        // Script tags for js links
198
        foreach ($this->getJavascript() as $file => $attributes) {
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            // Build html attributes
200
            $htmlAttributes = [
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                'type' => isset($attributes['type']) ? $attributes['type'] : "application/javascript",
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                'src' => $this->pathForFile($file),
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                'nonce' => $nonce,
204
            ];
205
            if (!empty($attributes['async'])) {
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                $htmlAttributes['async'] = 'async';
207
            }
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            // defer is not allowed for module, ignore it as it does the same anyway
209
            if (!empty($attributes['defer']) && $htmlAttributes['type'] !== 'module') {
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                $htmlAttributes['defer'] = 'defer';
211
            }
212
            if (!empty($attributes['integrity'])) {
213
                $htmlAttributes['integrity'] = $attributes['integrity'];
214
            }
215
            if (!empty($attributes['crossorigin'])) {
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                $htmlAttributes['crossorigin'] = $attributes['crossorigin'];
217
            }
218
            if (!empty($attributes['cookie-consent'])) {
219
                $htmlAttributes['cookie-consent'] = $attributes['cookie-consent'];
220
            }
221
            $jsRequirements .= str_replace(' />', '>', HTML::createTag('script', $htmlAttributes));
222
            $jsRequirements .= "\n";
223
        }
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        // Add all inline JavaScript *after* including external files they might rely on
226
        foreach ($this->getCustomScripts() as $scriptId => $script) {
227
            $type = self::config()->enable_js_modules ? 'module' : 'application/javascript';
228
            $attributes = [
229
                'type' => $type,
230
                'nonce' => $nonce,
231
            ];
232
            // For cookie-consent, since the Requirements API does not support passing variables
233
            // we rely on last part of uniquness id
234
            if ($scriptId) {
235
                $parts = explode("-", $scriptId);
236
                $lastPart = array_pop($parts);
237
                if (in_array($lastPart, self::listCookieTypes())) {
238
                    $attributes['type'] = 'text/plain';
239
                    $attributes['cookie-consent'] = $lastPart;
240
                }
241
            }
242
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            // Wrap script in a DOMContentLoaded
244
            // Make sure we don't add the eventListener twice (this will only work for simple scripts)
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            // Make sure we don't wrap scripts concerned by security policies
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            // Js modules are deferred by default, even if they are inlined, so not wrapping needed
247
            // @link https://stackoverflow.com/questions/41394983/how-to-defer-inline-javascript
248
            if (empty($attributes['cookie-consent']) && strpos($script, 'window.addEventListener') === false && !self::config()->enable_js_modules) {
249
                $script = "window.addEventListener('DOMContentLoaded', function() { $script });";
250
            }
251
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            // Remove comments if any
253
            $script = preg_replace('/(?:(?:\/\*(?:[^*]|(?:\*+[^*\/]))*\*+\/)|(?:(?<!\:|\\\|\'|\")\/\/.*))/', '', $script);
254
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            $jsRequirements .= HTML::createTag(
256
                'script',
257
                $attributes,
258
                "//<![CDATA[\n{$script}\n//]]>"
259
            );
260
            $jsRequirements .= "\n";
261
        }
262
263
        // Custom head tags (comes first)
264
        foreach ($this->getCustomHeadTags() as $customHeadTag) {
265
            $requirements .= "{$customHeadTag}\n";
266
        }
267
268
        // CSS file links
269
        foreach ($this->getCSS() as $file => $params) {
270
            $htmlAttributes = [
271
                'rel' => 'stylesheet',
272
                'type' => 'text/css',
273
                'href' => $this->pathForFile($file),
274
            ];
275
            if (!empty($params['media'])) {
276
                $htmlAttributes['media'] = $params['media'];
277
            }
278
            $requirements .= str_replace(' />', '>', HTML::createTag('link', $htmlAttributes));
279
            $requirements .= "\n";
280
        }
281
282
        // Literal custom CSS content
283
        foreach ($this->getCustomCSS() as $css) {
284
            $requirements .= HTML::createTag('style', ['type' => 'text/css'], "\n{$css}\n");
285
            $requirements .= "\n";
286
        }
287
288
        // Inject CSS  into body
289
        $content = $this->insertTagsIntoHead($requirements, $content);
290
291
        // Inject scripts
292
        if ($this->getForceJSToBottom()) {
293
            $content = $this->insertScriptsAtBottom($jsRequirements, $content);
294
        } elseif ($this->getWriteJavascriptToBody()) {
295
            $content = $this->insertScriptsIntoBody($jsRequirements, $content);
296
        } else {
297
            $content = $this->insertTagsIntoHead($jsRequirements, $content);
298
        }
299
        return $content;
300
    }
301
}
302