impl missing_cells_for_column_sidecar

beacon_node/beacon_chain/src/pending_payload_cache/mod.rs

@@ -174,14 +174,30 @@ impl<T: BeaconChainTypes> PendingPayloadCache<T> {
         })
     }
 
-    /// Checks if a specific data column is cached for the given block root.
+    /// Filter out cells that are already cached for the given column sidecar.
+    /// Returns the cells that still need KZG verification, or `None` if all cells are cached.
     #[instrument(skip_all, level = "trace")]
     pub fn missing_cells_for_column_sidecar<'a>(
         &'_ self,
         data_column: &'a DataColumnSidecar<T::EthSpec>,
     ) -> Result<Option<PartialDataColumnSidecarRef<'a, T::EthSpec>>, MissingCellsError> {
-        // TODO(gloas): implement cell-level missing check
+        let block_root = data_column.block_root();
-        Ok(None)
+        let column_index = *data_column.index();
+
+        self.peek_pending_components(&block_root, |components| {
+            let Some(cached) = components.and_then(|c| c.verified_data_columns.get(&column_index))
+            else {
+                return data_column.try_filter_to_partial_ref(|_, _, _| Ok(true));
+            };
+
+            data_column.try_filter_to_partial_ref(|cell_idx, cell, proof| {
+                match cached.cell_matches(cell_idx, cell, proof) {
+                    None => Ok(true),
+                    Some(true) => Ok(false),
+                    Some(false) => Err(MissingCellsError::MismatchesCachedColumn),
+                }
+            })
+        })
     }
 
     /// Insert an executed payload envelope into the cache and performs an availability check

beacon_node/beacon_chain/src/pending_payload_cache/pending_column.rs

@@ -19,12 +19,23 @@ impl<E: EthSpec> PendingColumn<E> {
         if let Some(existing_cell) = self.cells.get_mut(index)
             && existing_cell.is_none()
         {
-            *existing_cell = Some((cell.clone(), proof));
+            *existing_cell = Some((cell.clone(), *proof));
         }
     }
 
     // TODO(gloas): insert_from_partial
 
+    pub fn has_cell(&self, index: usize) -> bool {
+        self.cells.get(index).is_some_and(|c| c.is_some())
+    }
+
+    pub fn cell_matches(&self, index: usize, cell: &Cell<E>, proof: &KzgProof) -> Option<bool> {
+        self.cells
+            .get(index)?
+            .as_ref()
+            .map(|(c, p)| c == cell && p == proof)
+    }
+
     pub fn is_complete(&self, blob_count: usize) -> bool {
         self.cells.len() == blob_count && self.cells.iter().all(|cell| cell.is_some())
     }
@@ -49,7 +60,7 @@ impl<E: EthSpec> PendingColumn<E> {
             };
             // TODO(gloas): we likely want to go and arc all cells
             column.push(cell.clone());
-            kzg_proofs.push(proof);
+            kzg_proofs.push(*proof);
         }
 
         Some(Arc::new(DataColumnSidecar::Gloas(DataColumnSidecarGloas {