>>> [!note] Migrated issue <!-- Drupal.org comment --> <!-- Migrated from issue #3624079. --> Reported by: [mogtofu33](https://www.drupal.org/user/278510) Related to !569 >>> <h3>Problem/Motivation</h3> <p>Cache metadata a formatter returns is lost when the field is rendered through <code>FieldFormatterSource</code>. Pages are not invalidated when they should be. Two causes, both in <code>FieldFormatterSource</code>.</p> <p><strong>1. The top level <code>#cache</code> of the field build is dropped.</strong></p> <p><code>viewFieldItems()</code> keeps only the numeric children of the build:</p> <div class="codeblock"> <pre><span style="color: #000000"><span style="color: #0000BB">&lt;?php<br>$rendered_field </span><span style="color: #007700">= </span><span style="color: #0000BB">$items</span><span style="color: #007700">-&gt;</span><span style="color: #0000BB">view</span><span style="color: #007700">(</span><span style="color: #0000BB">$formatter_config</span><span style="color: #007700">);<br>for (</span><span style="color: #0000BB">$field_index </span><span style="color: #007700">= </span><span style="color: #0000BB">0</span><span style="color: #007700">; </span><span style="color: #0000BB">$field_index </span><span style="color: #007700">&lt; </span><span style="color: #0000BB">$items</span><span style="color: #007700">-&gt;</span><span style="color: #0000BB">count</span><span style="color: #007700">(); ++</span><span style="color: #0000BB">$field_index</span><span style="color: #007700">) {<br>&nbsp; if (!isset(</span><span style="color: #0000BB">$rendered_field</span><span style="color: #007700">[</span><span style="color: #0000BB">$field_index</span><span style="color: #007700">])) {<br>&nbsp;&nbsp;&nbsp; continue;<br>&nbsp; }<br>&nbsp; </span><span style="color: #0000BB">$returned</span><span style="color: #007700">[] = </span><span style="color: #0000BB">$rendered_field</span><span style="color: #007700">[</span><span style="color: #0000BB">$field_index</span><span style="color: #007700">];<br>}<br></span><span style="color: #0000BB">?&gt;</span></span></pre></div> <p>Core puts cacheability on that top level, not on the items:</p> <ul> <li><code>FormatterBase::view()</code>: the item list cacheability of computed fields, since <span class="drupalorg-gitlab-issue-link project-issue-status-info project-issue-status-7"><a href="https://www.drupal.org/project/drupal/issues/3304772" title="Status: Closed (fixed)">#3304772: Cache tags from Computed fields do not bubble up to Entity render array</a></span>.</li> <li><code>EntityReferenceFormatterBase::view()</code>: the access cacheability of referenced entities the user cannot view. When the referenced node is unpublished, its <code>node:ID</code> tag is lost, so publishing it does not invalidate the page.</li> </ul> <p><strong>2. Computed field cacheability is lost before the formatter runs.</strong></p> <p>The source passes its contexts to the formatter in <code>third_party_settings</code>, entity context included. <code>EntityViewBuilder::getSingleFieldDisplay()</code> builds its static cache key with <code>serialize($display_options)</code>. Serializing the entity calls <code>ContentEntityBase::__sleep()</code> on the live object: field values move to <code>$this-&gt;values</code> and the field objects are dropped.</p> <p>The display then calls <code>$entity-&gt;get()</code>, which builds a new list from the stored values. <code>ComputedItemListTrait::setValue()</code> marks it computed, so <code>computeValue()</code> never runs and the list has no cacheability. <code>FormatterBase::view()</code> applies an empty one. Fixing cause 1 alone is not enough for computed fields.</p> <h3>Steps to reproduce</h3> <p>Two kernel tests in <code>ComponentCacheabilityTest</code>, both failing on 2.0.x:</p> <ul> <li><code>testComputedFieldFormatter()</code>: renders <code>computed_test_cacheable_integer_field</code> from <code>entity_test</code> with <code>number_integer</code>. The value renders, but <code>field:computed_test_cacheable_integer_field</code> is not bubbled.</li> <li><code>testReferenceFormatterDeniedEntity()</code>: renders a reference to an unpublished node with <code>entity_reference_label</code>. The label is hidden, but <code>node:ID</code> is not bubbled.</li> </ul> <h3>Proposed resolution</h3> <p>In <code>viewFieldItems()</code>, add the top level cacheability of the build to the source. <code>ComponentElementBuilder::buildSource()</code> already applies the source cacheability to the component:</p> <div class="codeblock"> <pre><span style="color: #000000"><span style="color: #0000BB">&lt;?php<br>$rendered_field </span><span style="color: #007700">= </span><span style="color: #0000BB">$items</span><span style="color: #007700">-&gt;</span><span style="color: #0000BB">view</span><span style="color: #007700">(</span><span style="color: #0000BB">$formatter_config</span><span style="color: #007700">);<br></span><span style="color: #0000BB">$this</span><span style="color: #007700">-&gt;</span><span style="color: #0000BB">addCacheableDependency</span><span style="color: #007700">(</span><span style="color: #0000BB">CacheableMetadata</span><span style="color: #007700">::</span><span style="color: #0000BB">createFromRenderArray</span><span style="color: #007700">(</span><span style="color: #0000BB">$rendered_field</span><span style="color: #007700">));<br></span><span style="color: #0000BB">?&gt;</span></span></pre></div> <p>In <code>getPropValue()</code>, add the item list the source holds. It was computed before serialization and keeps its cacheability. Being outside <code>viewFieldItems()</code>, it also applies to the delta branch, where <code>FieldItemInterface::view()</code> returns only the item. The delta branch has no test, and it still loses the top level cacheability of other formatters, like the reference access one:</p> <div class="codeblock"> <pre><span style="color: #000000"><span style="color: #0000BB">&lt;?php<br>$value </span><span style="color: #007700">= </span><span style="color: #0000BB">$this</span><span style="color: #007700">-&gt;</span><span style="color: #0000BB">viewFieldItems</span><span style="color: #007700">(</span><span style="color: #0000BB">$items</span><span style="color: #007700">, </span><span style="color: #0000BB">$field_index</span><span style="color: #007700">);<br>if (</span><span style="color: #0000BB">$items </span><span style="color: #007700">instanceof </span><span style="color: #0000BB">CacheableDependencyInterface</span><span style="color: #007700">) {<br>&nbsp; </span><span style="color: #0000BB">$this</span><span style="color: #007700">-&gt;</span><span style="color: #0000BB">addCacheableDependency</span><span style="color: #007700">(</span><span style="color: #0000BB">$items</span><span style="color: #007700">);<br>}<br>return </span><span style="color: #0000BB">$value</span><span style="color: #007700">;<br></span><span style="color: #0000BB">?&gt;</span></span></pre></div> <p>Not addressed here: serializing live contexts on every field render still resets the entity fields and has a cost. Passing contexts to the formatter without putting them in the display options would fix that. It is a bigger change, for a follow-up.</p> <h3>Remaining tasks</h3> <ul> <li>Review.</li> <li>Follow-up: stop serializing contexts through the display options.</li> </ul> > Related issue: [Issue #3613372](https://www.drupal.org/node/3613372)