bug #38679 [PhpUnitBridge] Add missing exporter function for PHPUnit …

…7 (alcaeus)

This PR was merged into the 4.4 branch.

Discussion
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[PhpUnitBridge] Add missing exporter function for PHPUnit 7

| Q             | A
| ------------- | ---
| Branch?       | 4.4
| Bug fix?      | yes
| New feature?  | no <!-- please update src/**/CHANGELOG.md files -->
| Deprecations? | no <!-- please update UPGRADE-*.md and src/**/CHANGELOG.md files -->
| License       | MIT

This adds a missing `exporter` function to the compatibility trait for PHPUnit constraints. This method is still required for PhpUnit 7.

Commits
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52e7d78 Add missing exporter function for PHPUnit 7

src/Symfony/Bridge/PhpUnit/Legacy/ConstraintTraitForV7.php

@@ -11,6 +11,8 @@
 
 namespace Symfony\Bridge\PhpUnit\Legacy;
 
+use SebastianBergmann\Exporter\Exporter;
+
 /**
  * @internal
  */
@@ -31,6 +33,15 @@ protected function additionalFailureDescription($other): string
         return $this->doAdditionalFailureDescription($other);
     }
 
+    protected function exporter(): Exporter
+    {
+        if (null !== $this->exporter) {
+            $this->exporter = new Exporter();
+        }
+
+        return $this->exporter;
+    }
+
     protected function failureDescription($other): string
     {
         return $this->doFailureDescription($other);