Suppress uncaught Hybridauth exceptions in e_user_provider

And add a check for those exceptions in
`social_ui::generateSocialLoginSection()`

Fixes: #4192

e107_handlers/user_handler.php

@@ -1171,6 +1171,8 @@ class e_user_provider
 
 		}
 
+		try
+		{
 			$this->respawnHybridauth();
 			$this->setProvider($provider);
 
@@ -1180,7 +1182,19 @@ class e_user_provider
 				$this->adapter = $this->hybridauth->getAdapter($providerId);
 			}
 		}
+		catch (\Hybridauth\Exception\InvalidArgumentException $e)
+		{
+			if (!$suppress_exceptions) throw $e;
+		}
+		catch (\Hybridauth\Exception\UnexpectedValueException $e)
+		{
+			if (!$suppress_exceptions) throw $e;
+		}
+	}
 
+	/**
+	 * @throws \Hybridauth\Exception\InvalidArgumentException
+	 */
 	private function respawnHybridauth()
 	{
 		$this->hybridauth = new Hybridauth\Hybridauth($this->_config);
@@ -1237,9 +1251,10 @@ class e_user_provider
 	/**
 	 * Get the social login providers for which we have adapters
 	 *
-	 * This function is slow! Please cache the output instead of calling it multiple times.
+	 * Despite this being a static method, it memoizes (caches) the slow reflection code in the {@link e107} registry
+	 * after the first run, so subsequent calls to this method are fast.
 	 *
-	 * @return array String list of supported providers. Empty if Hybridauth is broken.
+	 * @return string[] String list of supported providers. Empty if Hybridauth is broken.
 	 */
 	public static function getSupportedProviders()
 	{

e107_plugins/social/admin_config.php

@@ -606,6 +606,19 @@ class social_ui extends e_admin_ui
 
 		foreach ($provider_names as $provider_name)
 		{
+			// Check if the current configuration for the provider is valid
+			try
+			{
+				new e_user_provider($provider_name, [], false);
+			}
+			catch (\Hybridauth\Exception\InvalidArgumentException $e)
+			{
+				e107::getMessage()->addError("[{$e->getCode()}] {$e->getMessage()}");
+			}
+			catch (\Hybridauth\Exception\UnexpectedValueException $ignored)
+			{
+			}
+
 			$text .= $this->generateSocialLoginRow($provider_name, $readonly);
 		}
 

e107_tests/tests/unit/e_user_providerTest.php

@@ -115,4 +115,32 @@ class e_user_providerTest extends \Codeception\Test\Unit
 		$result = e_user_provider::getSupplementalFieldsOf("Vkontakte");
 		$this->assertTrue(array_key_exists('photo_size', $result));
 	}
+
+	public function testNewSuppressExceptions()
+	{
+		$this->assertInstanceOf(
+			e_user_provider::class,
+			new e_user_provider("Facebook", ["providers" => ["Facebook", ["enabled" => true]]])
+		);
+	}
+
+	public function testNewNoSuppressConfigurationException()
+	{
+		$this->expectException(\Hybridauth\Exception\InvalidArgumentException::class);
+		new e_user_provider(
+			"Facebook",
+			["providers" => ["Facebook" => ["enabled" => true]]],
+			false
+		);
+	}
+
+	public function testNewNoSuppressDisabledException()
+	{
+		$this->expectException(\Hybridauth\Exception\UnexpectedValueException::class);
+		new e_user_provider(
+			"Facebook",
+			["providers" => ["Facebook" => ["enabled" => false]]],
+			false
+		);
+	}
 }