SSViewer_DataPresenter   F
last analyzed

Complexity

Total Complexity 63

Size/Duplication

Total Lines 425
Duplicated Lines 0 %

Importance

Changes 0
Metric Value
eloc 150
dl 0
loc 425
rs 3.36
c 0
b 0
f 0
wmc 63

13 Methods

Rating   Name   Duplication   Size   Complexity  
A __construct() 0 13 3
B getPropertiesFromProvider() 0 45 8
A cacheIteratorProperties() 0 10 2
A cacheGlobalProperties() 0 9 2
A getObj() 0 7 2
A processTemplateOverride() 0 20 5
A getInjectedValue() 0 27 5
A castValue() 0 13 6
A popScope() 0 10 2
B __call() 0 24 8
A pushScope() 0 17 3
B getValueSource() 0 50 10
B obj() 0 31 7

How to fix   Complexity   

Complex Class

Complex classes like SSViewer_DataPresenter often do a lot of different things. To break such a class down, we need to identify a cohesive component within that class. A common approach to find such a component is to look for fields/methods that share the same prefixes, or suffixes.

Once you have determined the fields that belong together, you can apply the Extract Class refactoring. If the component makes sense as a sub-class, Extract Subclass is also a candidate, and is often faster.

While breaking up the class, it is a good idea to analyze how other classes use SSViewer_DataPresenter, and based on these observations, apply Extract Interface, too.

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<?php
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namespace SilverStripe\View;
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use InvalidArgumentException;
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use SilverStripe\Core\ClassInfo;
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use SilverStripe\ORM\FieldType\DBField;
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/**
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 * This extends SSViewer_Scope to mix in data on top of what the item provides. This can be "global"
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 * data that is scope-independant (like BaseURL), or type-specific data that is layered on top cross-cut like
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 * (like $FirstLast etc).
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 *
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 * It's separate from SSViewer_Scope to keep that fairly complex code as clean as possible.
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 */
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class SSViewer_DataPresenter extends SSViewer_Scope
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Bug introduced by
The type SilverStripe\View\SSViewer_Scope was not found. Maybe you did not declare it correctly or list all dependencies?

The issue could also be caused by a filter entry in the build configuration. If the path has been excluded in your configuration, e.g. excluded_paths: ["lib/*"], you can move it to the dependency path list as follows:

filter:
    dependency_paths: ["lib/*"]

For further information see https://scrutinizer-ci.com/docs/tools/php/php-scrutinizer/#list-dependency-paths

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17
{
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    /**
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     * List of global property providers
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     *
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     * @internal
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     * @var TemplateGlobalProvider[]|null
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     */
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    private static $globalProperties = null;
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    /**
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     * List of global iterator providers
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     *
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     * @internal
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     * @var TemplateIteratorProvider[]|null
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     */
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    private static $iteratorProperties = null;
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    /**
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     * Overlay variables. Take precedence over anything from the current scope
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     *
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     * @var array|null
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     */
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    protected $overlay;
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    /**
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     * Flag for whether overlay should be preserved when pushing a new scope
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     *
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     * @see SSViewer_DataPresenter::pushScope()
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     * @var bool
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     */
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    protected $preserveOverlay = false;
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    /**
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     * Underlay variables. Concede precedence to overlay variables or anything from the current scope
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     *
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     * @var array
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     */
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    protected $underlay;
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    /**
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     * @var object $item
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     * @var array $overlay
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     * @var array $underlay
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     * @var SSViewer_Scope $inheritedScope
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     */
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    public function __construct(
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        $item,
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        array $overlay = null,
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        array $underlay = null,
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        SSViewer_Scope $inheritedScope = null
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    ) {
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        parent::__construct($item, $inheritedScope);
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        $this->overlay = $overlay ?: [];
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        $this->underlay = $underlay ?: [];
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        $this->cacheGlobalProperties();
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        $this->cacheIteratorProperties();
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    }
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    /**
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     * Build cache of global properties
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     */
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    protected function cacheGlobalProperties()
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    {
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        if (self::$globalProperties !== null) {
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            return;
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        }
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        self::$globalProperties = $this->getPropertiesFromProvider(
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            TemplateGlobalProvider::class,
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            'get_template_global_variables'
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        );
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    }
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    /**
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     * Build cache of global iterator properties
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     */
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    protected function cacheIteratorProperties()
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    {
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        if (self::$iteratorProperties !== null) {
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            return;
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        }
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        self::$iteratorProperties = $this->getPropertiesFromProvider(
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            TemplateIteratorProvider::class,
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            'get_template_iterator_variables',
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            true // Call non-statically
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        );
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    }
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    /**
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     * @var string $interfaceToQuery
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     * @var string $variableMethod
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     * @var boolean $createObject
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     * @return array
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     */
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    protected function getPropertiesFromProvider($interfaceToQuery, $variableMethod, $createObject = false)
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    {
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        $methods = [];
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The assignment to $methods is dead and can be removed.
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        $implementors = ClassInfo::implementorsOf($interfaceToQuery);
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        if ($implementors) {
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Bug Best Practice introduced by
The expression $implementors of type array is implicitly converted to a boolean; are you sure this is intended? If so, consider using ! empty($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.

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120
            foreach ($implementors as $implementor) {
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                // Create a new instance of the object for method calls
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                if ($createObject) {
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                    $implementor = new $implementor();
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                    $exposedVariables = $implementor->$variableMethod();
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                } else {
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                    $exposedVariables = $implementor::$variableMethod();
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                }
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                foreach ($exposedVariables as $varName => $details) {
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                    if (!is_array($details)) {
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                        $details = [
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                            'method' => $details,
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                            'casting' => ViewableData::config()->uninherited('default_cast')
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                        ];
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                    }
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                    // If just a value (and not a key => value pair), use method name for both key and value
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                    if (is_numeric($varName)) {
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                        $varName = $details['method'];
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                    }
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                    // Add in a reference to the implementing class (might be a string class name or an instance)
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                    $details['implementor'] = $implementor;
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                    // And a callable array
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                    if (isset($details['method'])) {
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                        $details['callable'] = [$implementor, $details['method']];
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                    }
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                    // Save with both uppercase & lowercase first letter, so either works
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                    $lcFirst = strtolower($varName[0]) . substr($varName, 1);
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                    $result[$lcFirst] = $details;
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                    $result[ucfirst($varName)] = $details;
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                }
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            }
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        }
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        return $result;
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The variable $result does not seem to be defined for all execution paths leading up to this point.
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    }
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    /**
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     * Look up injected value - it may be part of an "overlay" (arguments passed to <% include %>),
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     * set on the current item, part of an "underlay" ($Layout or $Content), or an iterator/global property
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     *
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     * @param string $property Name of property
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     * @param array $params
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     * @param bool $cast If true, an object is always returned even if not an object.
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     * @return array|null
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     */
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    public function getInjectedValue($property, array $params, $cast = true)
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    {
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        // Get source for this value
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        $result = $this->getValueSource($property);
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        if (!array_key_exists('source', $result)) {
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            return null;
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        }
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        // Look up the value - either from a callable, or from a directly provided value
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        $source = $result['source'];
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        $res = [];
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        if (isset($source['callable'])) {
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            $res['value'] = $source['callable'](...$params);
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        } elseif (array_key_exists('value', $source)) {
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            $res['value'] = $source['value'];
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        } else {
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            throw new InvalidArgumentException(
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                "Injected property $property does't have a value or callable value source provided"
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            );
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        }
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        // If we want to provide a casted object, look up what type object to use
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        if ($cast) {
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            $res['obj'] = $this->castValue($res['value'], $source);
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        }
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        return $res;
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    }
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    /**
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     * Store the current overlay (as it doesn't directly apply to the new scope
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     * that's being pushed). We want to store the overlay against the next item
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     * "up" in the stack (hence upIndex), rather than the current item, because
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     * SSViewer_Scope::obj() has already been called and pushed the new item to
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     * the stack by this point
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     *
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     * @return SSViewer_Scope
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     */
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    public function pushScope()
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    {
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        $scope = parent::pushScope();
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        $upIndex = $this->getUpIndex() ?: 0;
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        $itemStack = $this->getItemStack();
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        $itemStack[$upIndex][SSViewer_Scope::ITEM_OVERLAY] = $this->overlay;
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        $this->setItemStack($itemStack);
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        // Remove the overlay when we're changing to a new scope, as values in
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        // that scope take priority. The exceptions that set this flag are $Up
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        // and $Top as they require that the new scope inherits the overlay
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        if (!$this->preserveOverlay) {
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            $this->overlay = [];
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        }
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        return $scope;
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    }
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    /**
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     * Now that we're going to jump up an item in the item stack, we need to
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     * restore the overlay that was previously stored against the next item "up"
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     * in the stack from the current one
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     *
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     * @return SSViewer_Scope
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     */
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    public function popScope()
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    {
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        $upIndex = $this->getUpIndex();
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        if ($upIndex !== null) {
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            $itemStack = $this->getItemStack();
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            $this->overlay = $itemStack[$upIndex][SSViewer_Scope::ITEM_OVERLAY];
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        }
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        return parent::popScope();
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    }
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    /**
247
     * $Up and $Top need to restore the overlay from the parent and top-level
248
     * scope respectively.
249
     *
250
     * @param string $name
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     * @param array $arguments
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     * @param bool $cache
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     * @param string $cacheName
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     * @return $this
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     */
256
    public function obj($name, $arguments = [], $cache = false, $cacheName = null)
257
    {
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        $overlayIndex = false;
259
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        switch ($name) {
261
            case 'Up':
262
                $upIndex = $this->getUpIndex();
263
                if ($upIndex === null) {
264
                    throw new \LogicException('Up called when we\'re already at the top of the scope');
265
                }
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                $overlayIndex = $upIndex; // Parent scope
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                $this->preserveOverlay = true; // Preserve overlay
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                break;
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            case 'Top':
270
                $overlayIndex = 0; // Top-level scope
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                $this->preserveOverlay = true; // Preserve overlay
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                break;
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            default:
274
                $this->preserveOverlay = false;
275
                break;
276
        }
277
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        if ($overlayIndex !== false) {
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            $itemStack = $this->getItemStack();
280
            if (!$this->overlay && isset($itemStack[$overlayIndex][SSViewer_Scope::ITEM_OVERLAY])) {
281
                $this->overlay = $itemStack[$overlayIndex][SSViewer_Scope::ITEM_OVERLAY];
282
            }
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        }
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        parent::obj($name, $arguments, $cache, $cacheName);
286
        return $this;
287
    }
288
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    /**
290
     * {@inheritdoc}
291
     */
292
    public function getObj($name, $arguments = [], $cache = false, $cacheName = null)
293
    {
294
        $result = $this->getInjectedValue($name, (array)$arguments);
295
        if ($result) {
296
            return $result['obj'];
297
        }
298
        return parent::getObj($name, $arguments, $cache, $cacheName);
299
    }
300
301
    /**
302
     * {@inheritdoc}
303
     */
304
    public function __call($name, $arguments)
305
    {
306
        // Extract the method name and parameters
307
        $property = $arguments[0];  // The name of the public function being called
308
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        // The public function parameters in an array
310
        $params = (isset($arguments[1])) ? (array)$arguments[1] : [];
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        $val = $this->getInjectedValue($property, $params);
313
        if ($val) {
314
            $obj = $val['obj'];
315
            if ($name === 'hasValue') {
316
                $result = ($obj instanceof ViewableData) ? $obj->exists() : (bool)$obj;
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$obj is always a sub-type of SilverStripe\View\ViewableData.
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317
            } elseif (is_null($obj) || (is_scalar($obj) && !is_string($obj))) {
318
                $result = $obj; // Nulls and non-string scalars don't need casting
319
            } else {
320
                $result = $obj->forTemplate(); // XML_val
321
            }
322
323
            $this->resetLocalScope();
324
            return $result;
325
        }
326
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        return parent::__call($name, $arguments);
328
    }
329
330
    /**
331
     * Evaluate a template override. Returns an array where the presence of
332
     * a 'value' key indiciates whether an override was successfully found,
333
     * as null is a valid override value
334
     *
335
     * @param string $property Name of override requested
336
     * @param array $overrides List of overrides available
337
     * @return array An array with a 'value' key if a value has been found, or empty if not
338
     */
339
    protected function processTemplateOverride($property, $overrides)
340
    {
341
        if (!array_key_exists($property, $overrides)) {
342
            return [];
343
        }
344
345
        // Detect override type
346
        $override = $overrides[$property];
347
348
        // Late-evaluate this value
349
        if (!is_string($override) && is_callable($override)) {
350
            $override = $override();
351
352
            // Late override may yet return null
353
            if (!isset($override)) {
354
                return [];
355
            }
356
        }
357
358
        return ['value' => $override];
359
    }
360
361
    /**
362
     * Determine source to use for getInjectedValue. Returns an array where the presence of
363
     * a 'source' key indiciates whether a value source was successfully found, as a source
364
     * may be a null value returned from an override
365
     *
366
     * @param string $property
367
     * @return array An array with a 'source' key if a value source has been found, or empty if not
368
     */
369
    protected function getValueSource($property)
370
    {
371
        // Check for a presenter-specific override
372
        $result = $this->processTemplateOverride($property, $this->overlay);
373
        if (array_key_exists('value', $result)) {
374
            return ['source' => $result];
375
        }
376
377
        // Check if the method to-be-called exists on the target object - if so, don't check any further
378
        // injection locations
379
        $on = $this->itemIterator ? $this->itemIterator->current() : $this->item;
380
        if (isset($on->$property) || method_exists($on, $property)) {
381
            return [];
382
        }
383
384
        // Check for a presenter-specific override
385
        $result = $this->processTemplateOverride($property, $this->underlay);
386
        if (array_key_exists('value', $result)) {
387
            return ['source' => $result];
388
        }
389
390
        // Then for iterator-specific overrides
391
        if (array_key_exists($property, self::$iteratorProperties)) {
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Bug introduced by
It seems like self::iteratorProperties can also be of type null; however, parameter $search of array_key_exists() does only seem to accept array, maybe add an additional type check? ( Ignorable by Annotation )

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

391
        if (array_key_exists($property, /** @scrutinizer ignore-type */ self::$iteratorProperties)) {
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392
            $source = self::$iteratorProperties[$property];
393
            /** @var TemplateIteratorProvider $implementor */
394
            $implementor = $source['implementor'];
395
            if ($this->itemIterator) {
396
                // Set the current iterator position and total (the object instance is the first item in
397
                // the callable array)
398
                $implementor->iteratorProperties(
399
                    $this->itemIterator->key(),
400
                    $this->itemIteratorTotal
401
                );
402
            } else {
403
                // If we don't actually have an iterator at the moment, act like a list of length 1
404
                $implementor->iteratorProperties(0, 1);
405
            }
406
407
            return ($source) ? ['source' => $source] : [];
408
        }
409
410
        // And finally for global overrides
411
        if (array_key_exists($property, self::$globalProperties)) {
412
            return [
413
                'source' => self::$globalProperties[$property] // get the method call
414
            ];
415
        }
416
417
        // No value
418
        return [];
419
    }
420
421
    /**
422
     * Ensure the value is cast safely
423
     *
424
     * @param mixed $value
425
     * @param array $source
426
     * @return DBField
427
     */
428
    protected function castValue($value, $source)
429
    {
430
        // If the value has already been cast, is null, or is a non-string scalar
431
        if (is_object($value) || is_null($value) || (is_scalar($value) && !is_string($value))) {
432
            return $value;
433
        }
434
435
        // Get provided or default cast
436
        $casting = empty($source['casting'])
437
            ? ViewableData::config()->uninherited('default_cast')
438
            : $source['casting'];
439
440
        return DBField::create_field($casting, $value);
441
    }
442
}
443