Views block duplicated contextual links

@steveworley thanks for the extensive report and patch! Next time, if you upload a patch, please select a 'test with' version and put the issue status on 'needs review' to make sure it is tested by the testbot. Really curious to see what this breaks.

Some initial points:

1. +++ b/core/modules/contextual/js/contextual.js
   @@ -147,4 +150,4 @@
   -})(jQuery, Drupal, drupalSettings, _, Backbone, window.JSON, window.sessionStorage);
   \ No newline at end of file
   +})(jQuery, Drupal, drupalSettings, _, Backbone, window.JSON, window.sessionStorage);
   

   Unrelated change, lets leave it out, for easier reviewing

2. +++ b/core/modules/views/src/Plugin/Block/ViewsBlockBase.php
   @@ -186,24 +186,10 @@ public function blockSubmit($form, FormStateInterface $form_state) {
   +   * @deprecated Contextual links applied via DisplayPluginBase.
       */
      protected function addContextualLinks(&$output, $block_type = 'block') {
   

   Deprecating it is fine, but we can't remove the contents of this method, other modules might rely on it.

3. +++ b/core/modules/views/src/Plugin/views/display/DisplayPluginBase.php
   @@ -2360,6 +2363,9 @@ public function buildRenderable(array $args = [], $cache = TRUE) {
   +    views_add_contextual_links($this->view->element, "block", $this->display['id']);
   

   This can't default to 'block' in the DisplayPluginBase right? That would mess with other displays.

Also, this needs tests. Not sure if there is any javascript test coverage for contextual filters at the moment (actually pretty sure there isn't), but we need some.

index 558ea10..87a7ad7 100644
--- a/core/modules/contextual/js/contextual.es6.js

--- a/core/modules/contextual/js/contextual.es6.js
+++ b/core/modules/contextual/js/contextual.es6.js

+++ b/core/modules/contextual/js/contextual.es6.js
@@ -160,6 +160,9 @@

@@ -160,6 +160,9 @@
         ids.push($(this).attr('data-contextual-id'));
       });
 
+      // Remove duplicates from the IDs array.
+      ids = _.uniq(ids);
+
       // Update all contextual links placeholders whose HTML is cached.
       var uncachedIDs = _.filter(ids, function initIfCached(contextualID) {
         var html = storage.getItem('Drupal.contextual.' + contextualID);
diff --git a/core/modules/contextual/js/contextual.js b/core/modules/contextual/js/contextual.js

diff --git a/core/modules/contextual/js/contextual.js b/core/modules/contextual/js/contextual.js
index 9093d97..c225b15 100644

index 9093d97..c225b15 100644
--- a/core/modules/contextual/js/contextual.js

--- a/core/modules/contextual/js/contextual.js
+++ b/core/modules/contextual/js/contextual.js

+++ b/core/modules/contextual/js/contextual.js
@@ -101,6 +101,9 @@

@@ -101,6 +101,9 @@
         ids.push($(this).attr('data-contextual-id'));
       });
 
+      // Remove duplicates from the IDs array.
+      ids = _.uniq(ids);
+

We now need to "compile" es6 js files like this (inside core/ dir):
yarn run build:js -- --file modules/contextual/js/contextual.es6.js
Doing that in this patch.
#4.1 is automatically done by the compiling action.
Fixing #4.2 as well.

What #4.3 talks about brings up the issue of how views_add_contextual_links() is built... that parameter seems like it is very special, it can be on of three hardcoded values , or:

 * If you are rendering a view and its contextual links in another location,
 *   you can pass in a different value for this parameter. However, you will
 *   also need to set 'contextual_links_locations' in your plugin annotation to
 *   indicate which view displays support having their contextual links
 *   rendered in the location you have defined.

So this isn't as straight forward as it may seem, so I'm not entirely sure about the proposed solution.
How do we know what to pass to views_add_contextual_links from DisplayPluginBase::buildRenderable() ?

Appologies, the interdiff came out wrong. Here is the good one.

I updated the Manuel Garcia's patch to 8.5.x, but it need tests too.

Re-rolled for 9.2

Applid patch from #18 on Drupal 9.3 and is working perfect.

The Needs Review Queue Bot tested this issue. It either no longer applies to Drupal core, or fails the Drupal core commit checks. Therefore, this issue status is now "Needs work".

Apart from a re-roll or rebase, this issue may need more work to address feedback in the issue or MR comments. To progress an issue, incorporate this feedback as part of the process of updating the issue. This helps other contributors to know what is outstanding.

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I created an issue fork and added the patch.

I am testing by placing the recent content block via block UI.

What I'm seeing is duplicate contextual links for the block and for the view itself.

The only duplicated link is edit view, which is the only one on the view links.

I have any issues with opening the contextual links when the block title is visible.

If the block title is hidden, the view links overlap the block links.

The MR is not working on D11.

Need to remove use of backbone code, removed in 11.2