Improve test coverage

Author: sebastianfeldmann

src/Runner/Installer.php

@@ -142,20 +142,16 @@ public function setHook(string $hook): Installer
             return $this;
         }
 
-        /** @var array<int,string>|false $hooks */
+        /** @var array<string> $hooks */
         $hooks = explode(',', $hook);
-        if ($hooks === false) {
-            throw new Exception\InvalidHookName('Invalid hook name \'' . $hook . '\'');
-        }
-
         $hooks = array_map('trim', $hooks);
 
         $hooksValidationCallback = static function (string $hook): bool {
             return !HookUtil::isInstallable($hook);
         };
         if (!empty(($invalidHooks = array_filter($hooks, $hooksValidationCallback)))) {
             throw new Exception\InvalidHookName(
-                'Invalid hook name \'' . implode(',', $invalidHooks) . '\''
+                'Invalid hook name \'' . implode('\', \'', $invalidHooks) . '\''
             );
         }
 

tests/unit/Runner/InstallerTest.php

@@ -120,6 +120,7 @@ public function testHookInstallationDeclined(): void
         $io->expects($this->atLeast(5))->method('ask')->willReturn('n');
 
         $runner = new Installer($io, $config, $repo, $template);
+        $runner->setHook('');
         $runner->run();
 
         $this->assertFileDoesNotExist($fakeRepo->getHookDir() . '/pre-commit');