| Conditions | 6 | 
| Paths | 6 | 
| Total Lines | 25 | 
| Code Lines | 15 | 
| Lines | 0 | 
| Ratio | 0 % | 
| Changes | 1 | ||
| Bugs | 0 | Features | 0 | 
| 1 | <?php  | 
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| 26 | protected function doValidation(ResponseInterface $response)  | 
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| 27 |     { | 
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| 28 | $bigFiles = [];  | 
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| 29 | |||
| 30 |         if ($response instanceof ResourcesAwareResponse) { | 
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| 31 |             foreach ($response->getResources() as $resource) { | 
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| 32 | $resourceSize = round($resource['transferSize'] / 1000);  | 
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| 33 | |||
| 34 |                 if ($resourceSize > $this->maxElementSize) { | 
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| 35 | $bigFiles[] = ['name' => $resource['name'], 'size' => $resourceSize];  | 
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| 36 | }  | 
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| 37 | }  | 
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| 38 | }  | 
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| 39 | |||
| 40 |         if (count($bigFiles) > 0) { | 
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| 41 | $message = "Some files were found that are too big (max: " . $this->maxElementSize . " KB):<ul>";  | 
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| 42 |             foreach ($bigFiles as $bigFile) { | 
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| 43 | $message .= '<li>File: ' . $bigFile['name'] . ', Size: ' . $bigFile['size'] . ' KB</li>';  | 
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| 44 | }  | 
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| 45 | $message .= "</ul>";  | 
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| 46 | $result = new CheckResult(CheckResult::STATUS_FAILURE, $message, count($bigFiles));  | 
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| 47 |             $result->addAttribute(new Attribute('resources', $response->getResources(), true)); | 
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| 48 | return $result;  | 
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| 49 | }  | 
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| 50 | }  | 
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| 51 | }  | 
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| 52 | 
Let’s take a look at an example:
In the above example, the authenticate() method works fine as long as you just pass instances of MyUser. However, if you now also want to pass a different implementation of User which does not have a getDisplayName() method, the code will break.
Available Fixes
Change the type-hint for the parameter:
Add an additional type-check:
Add the method to the interface: