feature: Uri::getQueryValue (#157)

closes #156

Author: Greg Bowler

src/Uri.php

@@ -324,6 +324,11 @@ public function getQuery():string {
 		return $this->query ?? "";
 	}
 
+	public function getQueryValue(string $key):?string {
+		parse_str($this->getQuery(), $queryVariables);
+		return $queryVariables[$key] ?? null;
+	}
+
 	/**
 	 * Retrieve the fragment component of the URI.
 	 *

test/phpunit/UriTest.php

@@ -579,4 +579,11 @@ public function testImmutability() {
 		$this->assertNotSame($uri, $uri->withQuery('q=abc'));
 		$this->assertNotSame($uri, $uri->withFragment('test'));
 	}
-}
+
+	public function testGetQueryValue() {
+		$uri = new Uri("example.com/test?name=cody&colour=orange");
+		self::assertSame("cody", $uri->getQueryValue("name"));
+		self::assertSame("orange", $uri->getQueryValue("colour"));
+		self::assertNull($uri->getQueryValue("age"));
+	}
+}