OutputContains Assertion

The OutputContains assertion checks that the output contains a given substring.

Syntax

```php
echo 'The quick brown fox jumps over the lazy dog';
```
<!-- doctest-contains: brown fox -->

How It Works

1. The code block executes and its output is captured
2. A simple str_contains() check determines if the expected substring appears in the actual output
3. The check is case-sensitive

When to Use

• When you only care about a specific part of the output
• When the full output is too long or variable to match exactly
• When surrounding output may change but the key content stays the same

Examples

Checking for a key in JSON output

echo json_encode(['name' => 'DocTest', 'version' => '1.0']);

Matching part of a formatted string

printf('Hello %s, you have %d messages', 'Alice', 5);