Fix: ControllerTester::execute. Fixes #1834

system/Test/ControllerTester.php

@@ -158,10 +158,17 @@ public function execute(string $method, ...$params)
 			if (is_string($response))
 			{
 				$output = $response;
+				$result->response()->setBody($output);
+				$result->setBody($output);
+			}
+			elseif (! empty($response) && ! empty($response->getBody()))
+			{
+				$result->setBody($response->getBody());
+			}
+			else
+			{
+				$result->setBody('');
 			}
-
-			$result->response()->setBody($output);
-			$result->setBody($output);
 		}
 
 		// If not response code has been sent, assume a success

tests/_support/Controllers/Popcorn.php

@@ -31,7 +31,7 @@ public function popper()
 
 	public function weasel()
 	{
-		$this->respond(['Nothing to see here'], 200);
+		$this->respond('', 200);
 	}
 
 	public function oops()
@@ -43,4 +43,16 @@ public function goaway()
 	{
 		return redirect()->to('/');
 	}
+
+	// @see https://github.com/codeigniter4/CodeIgniter4/issues/1834
+	public function index3()
+	{
+		$response = $this->response->setJSON([
+			'lang' => $this->request->getLocale(),
+		]);
+
+		//      echo var_dump($this->response->getBody());
+		return $response;
+	}
+
 }

tests/system/Test/ControllerTesterTest.php

@@ -95,7 +95,6 @@ public function testPopcornFailure()
 				->controller(\Tests\Support\Controllers\Popcorn::class)
 				->execute('pop');
 
-		$body = $result->getBody();
 		$this->assertEquals(567, $result->response()->getStatusCode());
 	}
 
@@ -107,7 +106,6 @@ public function testPopcornException()
 				->controller(\Tests\Support\Controllers\Popcorn::class)
 				->execute('popper');
 
-		$body = $result->getBody();
 		$this->assertEquals(500, $result->response()->getStatusCode());
 	}
 
@@ -163,6 +161,7 @@ public function testEmptyResponse()
 				->execute('weasel');
 
 		$body = $result->getBody(); // empty
+		$this->assertEmpty($body);
 		$this->assertFalse($result->isOK());
 	}
 
@@ -200,4 +199,15 @@ public function testFailsForward()
 		$this->assertNull($result->ohno('Hi'));
 	}
 
+	// @see https://github.com/codeigniter4/CodeIgniter4/issues/1834
+	public function testResponseOverriding()
+	{
+		$result = $this->withURI('http://example.com/rest/')
+				->controller(\Tests\Support\Controllers\Popcorn::class)
+				->execute('index3');
+
+		$response = json_decode($result->getBody());
+		$this->assertEquals('en', $response->lang);
+	}
+
 }