Preserve QExcell sheet tab colors in XLSX

src/io/excellOffice.test.ts

@@ -6,6 +6,7 @@ import {
   buildAutoFilterXml,
   buildHyperlinksXml,
   buildMergeCellsXml,
+  buildSheetPrXml,
   buildSheetViewsXml,
   createCellStyleRegistry,
   buildWorksheetRelationshipsXml,
@@ -23,6 +24,7 @@ import {
   worksheetXmlToFrozenPane,
   worksheetXmlToHyperlinks,
   worksheetXmlToMergedCells,
+  worksheetXmlToTabColor,
   xlsxStylesXmlToCellFormatTable,
   xlsxThemeXmlToColors,
   xlsxCellToText
@@ -681,6 +683,51 @@ describe("excellOffice OOXML helpers", () => {
     expect(imported.sheets[0].autoFilter).toBe("A1:D20");
   });
 
+  it("читает и записывает цвет вкладки листа XLSX через sheetPr tabColor", async () => {
+    expect(
+      worksheetXmlToTabColor({
+        worksheet: {
+          sheetPr: { tabColor: { rgb: "FF0F766E" } }
+        }
+      })
+    ).toBe("0F766E");
+    expect(
+      worksheetXmlToTabColor(
+        {
+          worksheet: {
+            sheetPr: { tabColor: { theme: "4" } }
+          }
+        },
+        ["000000", "FFFFFF", "1F497D", "EEECE1", "123456"]
+      )
+    ).toBe("123456");
+    expect(buildSheetPrXml("#0f766e")).toBe('<sheetPr><tabColor rgb="FF0F766E"/></sheetPr>');
+    expect(buildSheetPrXml("bad")).toBe("");
+
+    const blob = await exportXlsxBlob({
+      id: "book-1",
+      title: "Tab color.xlsx",
+      updatedAt: "2026-06-01T00:00:00.000Z",
+      activeSheet: "sheet-1",
+      sheets: [
+        {
+          id: "sheet-1",
+          name: "Color",
+          tabColor: "#0f766e",
+          frozenPane: { rows: 1 },
+          cells: { A1: "Header" }
+        }
+      ]
+    });
+    const zip = await JSZip.loadAsync(await blob.arrayBuffer());
+    const sheetXml = (await zip.file("xl/worksheets/sheet1.xml")?.async("string")) ?? "";
+    const imported = await importXlsxFile(new File([blob], "Tab color.xlsx", { type: blob.type }));
+
+    expect(sheetXml).toContain('<sheetPr><tabColor rgb="FF0F766E"/></sheetPr>');
+    expect(sheetXml.indexOf("<sheetPr>")).toBeLessThan(sheetXml.indexOf("<sheetViews>"));
+    expect(imported.sheets[0].tabColor).toBe("0F766E");
+  });
+
   it("создает OOXML chart part для диаграммы XLSX", () => {
     const xml = buildChartXml(
       {