Fix virtual segments bleeding to the client

Author: emyller

src/Flagsmith.php

@@ -370,8 +370,12 @@ traits: $traits,
 
         $segments = [];
         foreach ($evaluationResult->segments as $resultSegment) {
+            if (($resultSegment->metadata['flagsmith_id'] ?? null) === null) {
+                continue;  // Not a real segment, e.g. an identity override virtual segment
+            }
+
             $segment = new Segment();
-            $segment->id = (int) $resultSegment->key;
+            $segment->id = $resultSegment->metadata['flagsmith_id'];
             $segment->name = $resultSegment->name;
             $segments[] = $segment;
         }

tests/FlagsmithClientTest.php

@@ -306,12 +306,13 @@ public function testGetIdentitySegmentsNoTraits()
     public function testGetIdentitySegmentsWithValidTrait()
     {
         foreach (ClientFixtures::localEvalFlagsmith() as $flagsmith) {
-            $identifier = 'identifier';
-            $traits = (object)['foo' => 'bar'];
+            $identifier = 'overridden-id';  // Creates a virtual segment for the identity override
+            $traits = (object)['foo' => 'bar'];  // Matches the segment
 
             $segments = $flagsmith->getIdentitySegments($identifier, $traits);
             $this->assertEquals(count($segments), 1);
             $this->assertEquals($segments[0]->getName(), 'Test segment');
+            $this->assertSame(1, $segments[0]->id);
         }
     }