Fix boolean XLSX header parity

assets/profiler-engine.js

@@ -632,6 +632,22 @@
     });
   }
 
+  function xlsxHeaderText(value) {
+    if (typeof value === 'boolean') return value ? 'True' : 'False';
+    return value === null || value === undefined ? '' : String(value);
+  }
+
+  function normalizeXlsxBooleanHeaderCells(sheet) {
+    if (!sheet['!ref']) return;
+    var range = global.XLSX.utils.decode_range(sheet['!ref']);
+    for (var c = range.s.c; c <= range.e.c; c++) {
+      var cell = sheet[global.XLSX.utils.encode_cell({ r: range.s.r, c: c })];
+      if (cell && cell.t === 'b' && typeof cell.v === 'boolean') {
+        cell.w = xlsxHeaderText(cell.v);
+      }
+    }
+  }
+
   async function parseXLSX(arrayBuffer) {
     await loadSheetJS();
 
@@ -649,6 +665,7 @@
     var date1904 = !!(workbook.Workbook && workbook.Workbook.WBProps &&
                       workbook.Workbook.WBProps.date1904);
     stringifyXlsxDateCells(sheet, date1904);
+    normalizeXlsxBooleanHeaderCells(sheet);
     var records = global.XLSX.utils.sheet_to_json(sheet, { defval: null, raw: true });
 
     if (records.length === 0) {
@@ -658,7 +675,7 @@
       // read the raw header row instead of erroring, to match.
       var headerRow = global.XLSX.utils.sheet_to_json(sheet, { header: 1, raw: true })[0] || [];
       var columns = headerRow.map(function (h) {
-        return h === null || h === undefined ? '' : String(h);
+        return xlsxHeaderText(h);
       });
       return { table: { columns: columns, rows: [] }, ignoredSheets: workbook.SheetNames.slice(1), sheetName: sheetName };
     }

tests/test_xlsx_edge_cases.py

@@ -221,3 +221,22 @@ def test_xlsx_numeric_header_cells_are_text_in_both_engines(tmp_path):
     js = [d["name"] for d in json.loads(result.stdout)["dimensions"]]
     assert py == js == ["2020", "sex"]
     assert all(isinstance(name, str) for name in py)
+
+
+@requires_openpyxl
+def test_xlsx_boolean_header_cells_match_python_text_in_both_engines(tmp_path):
+    """#1143: boolean headers use Python's "True"/"False" spelling, without changing text headers."""
+    from faircode import profile
+
+    wb = openpyxl.Workbook()
+    ws = wb.active
+    ws.append([True, False, "TRUE", "FALSE", "sex"])
+    for i in range(30):
+        ws.append([i % 3, (i + 1) % 2, i % 2, (i + 1) % 2, "m" if i % 2 else "f"])
+    path = _save_workbook(tmp_path, wb, "boolean_header.xlsx")
+    py = [d["name"] for d in profile(read_table(str(path)))["dimensions"]]
+    result = _run_js_parse(path)
+    assert result.returncode == 0, result.stderr
+    js = [d["name"] for d in json.loads(result.stdout)["dimensions"]]
+    assert py == js == ["True", "False", "TRUE", "FALSE", "sex"]
+    assert all(isinstance(name, str) for name in py)