Let rememberChoicePerIdp render the mock WAYF checkbox on its own

# Why is this change needed?
Prior to this change, the mock WAYF page only showed the remember my choice
checkbox in per-SP mode when both rememberChoiceFeature and
rememberChoicePerIdp were passed. In production only one mode can be enabled,
so the per-SP mode never has the global flag set. The parameter was also
missing from the testing docs.

# How does it address the issue?
This change makes rememberChoicePerIdp imply the feature, like in production,
and documents both modes and example links in docs/testing.md and
docs/js_testing.md.

Author: kayjoosten

docs/js_testing.md

@@ -42,7 +42,8 @@ parameters can be used to manipulate the behaviour of the wayf that is rendered.
 | **Query parameter** | **Default value** | **Explanation** |
 |---|----|----|
 | displayUnconnectedIdpsWayf | (bool) false | Type: boolean. Display unconnected IdPs on the WAYF. |
-| rememberChoiceFeature | (bool) false | Type: boolean. Display the remember choice feature. |
+| rememberChoiceFeature | (bool) false | Type: boolean. Display the remember choice feature in global mode. |
+| rememberChoicePerIdp | (bool) false | Type: boolean. Display the remember choice feature in per-SP mode. Implies rememberChoiceFeature. |
 | cutoffPointForShowingUnfilteredIdps | (int) 100 | Type: integer. The number of IdPs to display on the WAYF before cutting them off. |
 | showIdpBanner | (bool) true | Type: boolean. Show the EduId (default IdP) banner on the WAYF or not |
 | defaultIdpEntityId | (string) null | Type: string. The entityId of the default IdP (EduId) |

docs/testing.md

@@ -20,7 +20,8 @@ The functional-testing route renders the WAYF page with synthetic IdP data, cont
 | `showIdPBanner` | bool | `true` | Whether to show the default IdP banner |
 | `displayUnconnectedIdpsWayf` | bool | `false` | Show unconnected IdPs with a "Request access" button |
 | `backLink` | bool | `false` | Show "Return to service provider" back link |
-| `rememberChoiceFeature` | bool | `false` | Show "Remember my choice" checkbox |
+| `rememberChoiceFeature` | bool | `false` | Show "Remember my choice" checkbox (global mode: the choice is stored in the `rememberchoice` cookie) |
+| `rememberChoicePerIdp` | bool | `false` | Show "Remember my choice" checkbox in per-SP mode (the choice is stored in the `rememberedidps` cookie). Implies `rememberChoiceFeature`, like in production where only one of the two modes can be enabled |
 | `cutoffPointForShowingUnfilteredIdps` | int | `100` | Hide the IdP list until the user searches when list length exceeds this value |
 
 #### Baseline
@@ -38,7 +39,8 @@ The functional-testing route renders the WAYF page with synthetic IdP data, cont
 
 #### UI features
 - [Back link](https://engine.dev.openconext.local/functional-testing/wayf?backLink=true)
-- [Remember my choice](https://engine.dev.openconext.local/functional-testing/wayf?rememberChoiceFeature=true)
+- [Remember my choice (global mode)](https://engine.dev.openconext.local/functional-testing/wayf?rememberChoiceFeature=true)
+- [Remember my choice (per-SP mode)](https://engine.dev.openconext.local/functional-testing/wayf?rememberChoicePerIdp=true)
 - [Default IdP banner](https://engine.dev.openconext.local/functional-testing/wayf?defaultIdpEntityId=https%3A%2F%2Fexample.com%2FentityId%2F3&showIdPBanner=true&addDiscoveries=false)
 
 #### Preferred IdPs

src/OpenConext/EngineBlockFunctionalTestingBundle/Controllers/WayfController.php

@@ -67,7 +67,7 @@ public function wayfAction(Request $request)
             shouldDisplayBanner: $showIdPBanner,
             backLink: $backLink,
             cutoffPoint: $cutoffPointForShowingUnfilteredIdps,
-            rememberChoice: $rememberChoiceFeature,
+            rememberChoice: $rememberChoiceFeature || $rememberChoicePerIdp,
             showRequestAccess: $displayUnconnectedIdpsWayf,
             requestId: 'bogus-request-id',
             serviceProvider: TestEntitySeeder::buildSp(),