| Conditions | 3 | 
| Paths | 3 | 
| Total Lines | 11 | 
| Code Lines | 7 | 
| Lines | 7 | 
| Ratio | 63.64 % | 
| Changes | 0 | ||
| 1 | <?php  | 
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| 26 | public function testToArray()  | 
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| 27 |     { | 
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| 28 | $array = $this->source->toArray();  | 
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| 29 | View Code Duplication |         foreach ($array as $item) { | 
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| 30 |             $this->assertInternalType('array', $item); | 
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| 31 |             foreach ($item as $key => $value) { | 
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| 32 |                 $this->assertInternalType('string', $key); | 
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| 33 | $this->assertInstanceOf(\Magento\Framework\Phrase::class, $value);  | 
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| 34 | }  | 
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| 35 | }  | 
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| 36 | }  | 
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| 37 | }  | 
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| 38 | 
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: