From 9a58f2d086ae56d4b254bf101e48388815cb2b46 Mon Sep 17 00:00:00 2001
From: Marco Arnulfo <marcoarnulfo1@gmail.com>
Date: Mon, 12 Oct 2026 22:40:01 +0200
Subject: [PATCH] XLS: a formula kept as its saved value keeps a text result
 (fixes #802)

---
 crates/xlsx/src/tests/xls_tests.rs | 15 +++++++++++++++
 crates/xlsx/src/xls/mod.rs         | 10 +++++++---
 2 files changed, 22 insertions(+), 3 deletions(-)

diff --git a/crates/xlsx/src/tests/xls_tests.rs b/crates/xlsx/src/tests/xls_tests.rs
index fd37795..f008883 100644
--- a/crates/xlsx/src/tests/xls_tests.rs
+++ b/crates/xlsx/src/tests/xls_tests.rs
@@ -358,6 +358,21 @@ fn reads_values_formulas_formats_and_layout() {
     assert_eq!(wb.date_system, DateSystem::D1904);
 }
 
+#[test]
+fn text_result_of_a_formula_kept_as_its_value() {
+    // A what-if data table cell ({=TABLE(B1,)}) can't be imported as a formula, so its saved result
+    // is kept. With the default XF the cell is blank until the String record brings the text.
+    let table = cat(&[&[0x02], &u16s(&[0, 0])]);
+    let sheet = cat(&[&bof(0x0010), &formula(0, 0, special(0, 0), &table), &rec(0x0207, &xlstr("103a")), &eof()]);
+    let boundsheet = |pos: u32| rec(0x0085, &cat(&[&pos.to_le_bytes(), &[0, 0, 6, 0], b"Sheet1"]));
+    let len = cat(&[&bof(0x0005), &boundsheet(0), &eof()]).len() as u32;
+    let stream = cat(&[&bof(0x0005), &boundsheet(len), &eof(), &sheet]);
+    let (wb, report) = read_xls(&compound("Workbook", &stream)).unwrap();
+    assert!(report.warnings.iter().any(|w| w.contains("what-if data tables")), "{:?}", report.warnings);
+    assert_eq!(ftext(&wb, "A1"), None);
+    assert_eq!(v(&wb, 0, "A1"), Value::from("103a"));
+}
+
 #[test]
 fn refuses_encrypted_old_and_foreign_files() {
     // FILEPASS in the globals: an encrypted workbook.
diff --git a/crates/xlsx/src/xls/mod.rs b/crates/xlsx/src/xls/mod.rs
index c9aee66..0e9fb64 100644
--- a/crates/xlsx/src/xls/mod.rs
+++ b/crates/xlsx/src/xls/mod.rs
@@ -390,7 +390,9 @@ struct SheetState<'g> {
     shared: HashMap<CellRef, Parsed>,
     arrays: HashMap<CellRef, (RangeRef, Parsed)>,
     last_formula: Option<CellRef>,
-    pending_string: Option<CellRef>,
+    /// The cell waiting for its String record, with its style: a blank cell isn't stored, so a
+    /// formula kept as its value may have no cell to receive the text.
+    pending_string: Option<(CellRef, StyleId)>,
     dropped: usize,
     unsupported: Vec<&'static str>,
 }
@@ -594,11 +596,13 @@ fn sheet_record(rec: &Record<'_>, st: &mut SheetState<'_>, budget: &mut Budget,
         }
         0x0006 => formula_cell(&mut c, st, budget)?,
         0x0207 => {
-            if let Some(pos) = st.pending_string.take() {
+            if let Some((pos, style)) = st.pending_string.take() {
                 let s = c.string()?;
                 budget.text(s.len())?;
                 if let Some(cell) = st.sheet.cells.get_mut(pos) {
                     cell.value = Value::from(s);
+                } else {
+                    st.sheet.cells.set(pos, Cell { value: Value::from(s), formula: None, style });
                 }
             }
         }
@@ -736,7 +740,7 @@ fn formula_cell(c: &mut Cursor<'_, '_>, st: &mut SheetState<'_>, budget: &mut Bu
     st.sheet.cells.set(pos, Cell { value, formula: None, style });
     st.last_formula = Some(pos);
     if string_result {
-        st.pending_string = Some(pos);
+        st.pending_string = Some((pos, style));
     }
     // PtgExp: part of a shared or array formula anchored at another cell.
     if f.rgce.len() == 5 && f.rgce.first() == Some(&0x01) {