perf: memoize segment convention detection (#153)

Author: konradmichalik

src/Validator/ConventionDetector.php

@@ -25,6 +25,15 @@
  */
 final class ConventionDetector
 {
+    /**
+     * Cache of matched conventions per segment string. Segments (e.g. "label",
+     * "title") repeat heavily across keys, so caching avoids re-running every
+     * convention regex for the same segment.
+     *
+     * @var array<string, array<string>>
+     */
+    private array $segmentConventionCache = [];
+
     /**
      * Detect which conventions a key matches.
      *
@@ -84,6 +93,10 @@ public function detectKeyConventions(string $key): array
      */
     public function detectSegmentConventions(string $segment): array
     {
+        if (isset($this->segmentConventionCache[$segment])) {
+            return $this->segmentConventionCache[$segment];
+        }
+
         $matchingConventions = [];
 
         foreach (KeyNamingConvention::cases() as $convention) {
@@ -97,7 +110,7 @@ public function detectSegmentConventions(string $segment): array
             $matchingConventions[] = 'unknown';
         }
 
-        return $matchingConventions;
+        return $this->segmentConventionCache[$segment] = $matchingConventions;
     }
 
     /**

tests/src/Validator/ConventionDetectorTest.php

@@ -33,6 +33,14 @@ protected function setUp(): void
         $this->detector = new ConventionDetector();
     }
 
+    public function testDetectSegmentConventionsIsMemoized(): void
+    {
+        $first = $this->detector->detectSegmentConventions('label');
+        $second = $this->detector->detectSegmentConventions('label');
+
+        $this->assertSame($first, $second);
+    }
+
     /**
      * @param array<string> $expectedContains
      * @param array<string> $expectedNotContains