test: add test for getJSON() and JSON_THROW_ON_ERROR

Author: kenjis

tests/system/HTTP/IncomingRequestTest.php

@@ -18,6 +18,7 @@
 use CodeIgniter\Test\CIUnitTestCase;
 use Config\App;
 use InvalidArgumentException;
+use JsonException;
 use TypeError;
 
 /**
@@ -541,6 +542,19 @@ public function testGetJSONWithInvalidJSONString(): void
         $request->getJSON();
     }
 
+    public function testGetJSONWithJsonThrowOnErrorAndInvalidJSONString(): void
+    {
+        $this->expectException(JsonException::class);
+        $this->expectExceptionMessage('Syntax error');
+
+        $config          = new App();
+        $config->baseURL = 'http://example.com/';
+        $json            = 'Invalid JSON string';
+        $request         = $this->createRequest($config, $json);
+
+        $request->getJSON(false, 512, JSON_THROW_ON_ERROR);
+    }
+
     public function testCanGrabGetRawInput(): void
     {
         $rawstring = 'username=admin001&role=administrator&usepass=0';