[IMP] CellPlugin: Avoid useless UPDATE_CELL

The CellPlugin handler for "DELETE_CONTENT" will dispatch an UPDATE_CELL
to empty its content regardless of the cell. On a big zone this can end
up being quite costly as we pass for no reason in all the plugins and
stores to apply 0 changes, it only adds some overhead.

the allowDispatch of UPDATE_CELL handles this case but in this case it's
a subcommand and the allowDispatch is bypassed.

Benchmark
=========

Measure of the execution time of `model.Dispatch` on a 26x100 cells
sheet with **styled** cells.

cells with content (formula or text)
- before: 120~140ms
- after: 120~140ms

cells without content
- before 120~140ms
- 4~9ms

closes #5283

Task: 4367772
Signed-off-by: Lucas Lefèvre (lul) <[email protected]>

src/plugins/core/cell.ts

@@ -162,7 +162,7 @@ export class CellPlugin extends CorePlugin<CoreState> implements CoreState {
       for (let col = zone.left; col <= zone.right; col++) {
         for (let row = zone.top; row <= zone.bottom; row++) {
           const cell = this.getters.getCell({ sheetId, col, row });
-          if (cell) {
+          if (cell?.isFormula || cell?.content) {
             this.dispatch("UPDATE_CELL", {
               sheetId: sheetId,
               content: "",
@@ -200,7 +200,6 @@ export class CellPlugin extends CorePlugin<CoreState> implements CoreState {
     for (let zone of recomputeZones(zones)) {
       for (let col = zone.left; col <= zone.right; col++) {
         for (let row = zone.top; row <= zone.bottom; row++) {
-          // commandHelpers.updateCell(sheetId, col, row, { style: undefined});
           this.dispatch("UPDATE_CELL", {
             sheetId,
             col,

tests/cells/cell_plugin.test.ts

@@ -1,7 +1,8 @@
-import { Model } from "../../src";
+import { CoreCommand, CorePlugin, Model } from "../../src";
 import { LINK_COLOR } from "../../src/constants";
 import { buildSheetLink, toZone } from "../../src/helpers";
 import { urlRepresentation } from "../../src/helpers/links";
+import { corePluginRegistry } from "../../src/plugins";
 import { CellValueType, CommandResult } from "../../src/types";
 import {
   addColumns,
@@ -11,6 +12,7 @@ import {
   copy,
   createSheet,
   deleteColumns,
+  deleteContent,
   deleteRows,
   deleteSheet,
   paste,
@@ -27,6 +29,7 @@ import {
   getEvaluatedCell,
   getStyle,
 } from "../test_helpers/getters_helpers";
+import { addTestPlugin } from "../test_helpers/helpers";
 
 describe("getCellText", () => {
   test("Update cell with a format is correctly set", () => {
@@ -643,4 +646,22 @@ describe("Cell dependencies and tokens are updated", () => {
       },
     });
   });
+
+  test("Do not dispatch UPDATE_CELL subcommands if the content is empty", () => {
+    let counter = 0;
+    class SubCommandCounterRange extends CorePlugin {
+      static getters = [];
+      handle(command: CoreCommand) {
+        if (command.type === "UPDATE_CELL") {
+          counter++;
+        }
+      }
+    }
+    addTestPlugin(corePluginRegistry, SubCommandCounterRange);
+    const model = new Model();
+    setStyle(model, "A1", { bold: true });
+    counter = 0;
+    deleteContent(model, ["A1"]);
+    expect(counter).toBe(0);
+  });
 });