[FIX] xlsx: cannot import CF with formulas

Importing a conditional formatting rule with formulas was not working
because the formulas are not prefixed by "=" in the xlsx file.

closes #6957

Task: 4945945
X-original-commit: 4b9a566
Signed-off-by: Rémi Rahir (rar) <rar@odoo.com>
Signed-off-by: Adrien Minne (adrm) <adrm@odoo.com>

Author: hokolomopo

src/xlsx/conversion/cf_conversion.ts

@@ -1,4 +1,5 @@
 import { ICON_SETS } from "../../components/icons/icons";
+import { tokenize } from "../../formulas";
 import {
   ColorScaleMidPointThreshold,
   ColorScaleThreshold,
@@ -75,9 +76,9 @@ export function convertConditionalFormats(
       case "cellIs":
         if (!rule.operator || !rule.formula || rule.formula.length === 0) continue;
         operator = convertCFCellIsOperator(rule.operator);
-        values.push(rule.formula[0]);
+        values.push(prefixFormula(rule.formula[0]));
         if (rule.formula.length === 2) {
-          values.push(rule.formula[1]);
+          values.push(prefixFormula(rule.formula[1]));
         }
         break;
     }
@@ -243,6 +244,12 @@ function convertIcons(xlsxIconSet: ExcelIconSet, index: number): string {
     : ICON_SETS[iconSet].good;
 }
 
+/** Prefix the string by "=" if the string looks like a formula */
+function prefixFormula(formula: string): string {
+  const tokens = tokenize(formula);
+  return tokens.length === 1 && tokens[0].type !== "REFERENCE" ? formula : "=" + formula;
+}
+
 // ---------------------------------------------------------------------------
 // Warnings
 // ---------------------------------------------------------------------------

tests/__xlsx__/xlsx_demo_data.xlsx

@@ -320,6 +320,15 @@ describe("Import xlsx data", () => {
     expect((cf.rule as CellIsRule).values).toEqual(values);
   });
 
+  test("Can import CF with formulas", () => {
+    const testSheet = getWorkbookSheet("jestCfs", convertedData)!;
+    const cf = getCFBeginningAt("B29", testSheet)!;
+
+    expect(cf.rule.type).toEqual("CellIsRule");
+    expect((cf.rule as CellIsRule).operator).toEqual("Between");
+    expect((cf.rule as CellIsRule).values).toEqual(["=$B$23", "=2+2"]);
+  });
+
   test.each([
     ["A2"], // number
     ["F2"], // time