Sheet transfer: preserve workbook references (builds on #1803 and #1200)

ROADMAP.md

@@ -2,7 +2,7 @@
 
 **Stage: alpha** · next: beta, ~25 points of "ready for real work" and ~160–240 h away
 
-> **Last reviewed:** 2026-10-11 · **Last updated:** 2026-10-12 · **Change:** minor (rows auto-fit oversized fonts on open and whole-row/column formatting) · **Target:** Microsoft Excel (Microsoft 365)
+> **Last reviewed:** 2026-10-11 · **Last updated:** 2026-10-14 · **Change:** minor (Workbook Links: linked workbooks update from their files) · **Target:** Microsoft Excel (Microsoft 365)
 
 GridCraft aims at full Microsoft Excel parity, and at being better in places: faster, open (XLSX
 is the native format), fully scriptable by agents (MCP, control channel, CLI), and on the web.
@@ -132,6 +132,7 @@ Ranked; estimates in Opus 5.5 agent-hours. Detail and the full beta-gate list in
 
 | Date | What landed |
 |---|---|
+| 2026-10-14 | Workbook Links: Data › Queries & Connections › Workbook Links (Excel 365's pane) and File › Info › Edit Links to Files update linked workbooks' values from their files, check their status, change their source, open them and break the links (formulas become values); the startup prompt is saved with the workbook. Opening a workbook with links shows the security warning with Enable Content instead of reading them. Builds on #464 (formulas into linked workbooks use the saved values) and #829 (references typed by file name go through a link) |
 | 2026-10-12 | Rows auto-fit oversized fonts: opening a file and whole-row/column formatting grow non-custom rows to their tallest font (#833) |
 | 2026-10-12 | Number formats: parsing a format code is linear in its length (long runs of `[`, `,` or `/` no longer take quadratic time), and an unclosed `[` is a literal when splitting sections as well as when tokenizing (#810) |
 | 2026-10-12 | Number formats: a fraction denominator with 65,536 zeros no longer crashes; format codes are capped at 255 characters like Excel (longer codes display as General, `TEXT` gives `#VALUE!`) (#807) |
@@ -193,6 +194,7 @@ Ranked; estimates in Opus 5.5 agent-hours. Detail and the full beta-gate list in
 
 | Date | Change | Summary |
 |---|---|---|
+| 2026-10-14 | minor | Progress log: Workbook Links (update, change source, break links, startup prompt, security warning) |
 | 2026-10-12 | minor | Rows auto-fit oversized fonts on open and whole-row/column formatting (#833); progress log row |
 | 2026-10-12 | minor | Progress log: multi-area row/column delete (#758) |
 | 2026-10-12 | trivial | Progress log: XLSX chart sheets kept on save (#727) |

crates/calc/src/recalc.rs

@@ -765,7 +765,7 @@ impl Host for PassHost<'_> {
     }
     fn used_range(&mut self, sheet: usize) -> Option<RangeRef> {
         let wb = self.wb;
-        *self.used.entry(sheet).or_insert_with(|| wb.sheet(sheet).and_then(|s| s.used_range()))
+        *self.used.entry(sheet).or_insert_with(|| crate::eval::used_range_of(wb, sheet))
     }
     fn now_serial(&self) -> f64 {
         self.now

crates/calc/src/tests.rs

@@ -94,6 +94,160 @@ fn chains_out_of_order() {
     assert_eq!(t.num("A5"), 5.0);
 }
 
+#[test]
+fn references_into_linked_workbooks_read_the_saved_values() {
+    use gridcraft_model::{ExternalBook, ExternalName, ExternalSheet};
+    let mut t = T::new();
+    let prices = ExternalSheet {
+        name: "P&L Prices".into(),
+        cells: vec![(c("A1"), Value::text("gas")), (c("B1"), Value::Number(4.5)), (c("A2"), Value::text("power")), (c("B2"), Value::Number(61.0))],
+        refresh_error: false,
+    };
+    let rates = ExternalSheet { name: "Rates".into(), cells: vec![(c("C3"), Value::Number(2.0))], refresh_error: false };
+    let failed = ExternalSheet { name: "Failed".into(), cells: vec![(c("A1"), Value::Number(9.0))], refresh_error: true };
+    let names = vec![
+        ExternalName { name: "Gas".into(), sheet: None, refers_to: "'P&L Prices'!$B$1".into() },
+        ExternalName { name: "Rate".into(), sheet: Some(1), refers_to: "$C$3".into() },
+        // Names inside a linked name are the linked workbook's too.
+        ExternalName { name: "GasTwice".into(), sheet: None, refers_to: "Gas*2".into() },
+        ExternalName { name: "RatePlus".into(), sheet: Some(1), refers_to: "Rate+GasTwice".into() },
+        // A sheet range or a sheetless reference in a workbook-level name can't be resolved
+        // from the saved values (and must not read this workbook's cells).
+        ExternalName { name: "Span".into(), sheet: None, refers_to: "Rates:Failed!$A$1".into() },
+        ExternalName { name: "Loose".into(), sheet: None, refers_to: "$E$9".into() },
+    ];
+    t.wb.external_books = vec![ExternalBook::default(), ExternalBook { sheets: vec![prices, rates, failed], names, ..Default::default() }].into();
+    t.wb.names.push(gridcraft_model::DefinedName {
+        name: "Price".into(),
+        scope: None,
+        formula: "'[2]P&L Prices'!$A$1:$B$65536".into(),
+        comment: String::new(),
+        hidden: false,
+    });
+    t.set("A1", "='[2]P&L Prices'!B2*2");
+    t.set("A2", "=VLOOKUP(\"gas\",Price,2,FALSE)");
+    t.set("A3", "=SUM('[2]P&L Prices'!B1:B9)+[2]Rates!C3");
+    t.set("A4", "=[2]Rates!A1");
+    assert_eq!((t.num("A1"), t.num("A2"), t.num("A3"), t.num("A4")), (122.0, 4.5, 67.5, 0.0));
+    // A sheet the link didn't save, or a book that isn't linked, is #REF! as before.
+    t.set("A5", "=[2]Other!A1");
+    t.set("A6", "=[1]Rates!C3");
+    t.set("A7", "='[3]Rates'!C3");
+    for at in ["A5", "A6", "A7"] {
+        assert_eq!(t.get(at), Value::Error(CellError::Ref), "{at}");
+    }
+    // A sheet whose last refresh failed keeps its saved cells; anything else in it is #REF!.
+    t.set("A8", "=[2]Failed!A1+[2]Failed!B1");
+    t.set("A9", "=[2]Failed!A1");
+    t.set("A10", "=SUM([2]Failed!A1:B1)");
+    assert_eq!((t.get("A8"), t.num("A9"), t.get("A10")), (Value::Error(CellError::Ref), 9.0, Value::Error(CellError::Ref)));
+    // `[0]` is the workbook itself: its names, sheets and sheet ranges (as files may hold them).
+    t.set("D1", "=VLOOKUP(\"power\",[0]!Price,2,FALSE)");
+    assert_eq!(t.num("D1"), 61.0);
+    t.set("D2", "=[0]Sheet1!A1+SUM([0]Sheet1:Sheet1!A1)");
+    assert_eq!(t.num("D2"), 244.0);
+    // The linked workbook's own names: workbook-scoped and sheet-scoped.
+    t.set("B1", "=[2]!Gas*10");
+    t.set("B2", "=[2]Rates!Rate+1");
+    assert_eq!((t.num("B1"), t.num("B2")), (45.0, 3.0));
+    t.set("B3", "=[2]!Missing");
+    assert_eq!(t.get("B3"), Value::Error(CellError::Ref));
+    t.set("E9", "100");
+    t.set("B4", "=[2]!GasTwice");
+    t.set("B5", "=[2]Rates!RatePlus");
+    t.set("B6", "=[2]!Span");
+    t.set("B7", "=[2]!Loose");
+    assert_eq!((t.num("B4"), t.num("B5")), (9.0, 11.0));
+    assert_eq!((t.get("B6"), t.get("B7")), (Value::Error(CellError::Ref), Value::Error(CellError::Ref)));
+    // SUMIF and friends need references; Excel can't read a closed workbook through them.
+    t.set("C1", "=SUMIF('[2]P&L Prices'!A1:A2,\"gas\",'[2]P&L Prices'!B1:B2)");
+    t.set("C2", "=COUNTIF(#REF!,\">0\")");
+    t.set("C3", "=SUMIF(Price,\"gas\")");
+    assert_eq!(
+        (t.get("C1"), t.get("C2"), t.get("C3")),
+        (Value::Error(CellError::Value), Value::Error(CellError::Ref), Value::Error(CellError::Value))
+    );
+    // Linked sheets print as Excel writes them: quoted only when the sheet name needs it.
+    let f = t.wb.sheet(0).unwrap().cells.get(c("A3")).and_then(|x| x.formula.clone()).unwrap();
+    assert_eq!(gridcraft_formula::print(f.expr.as_ref().unwrap()), "SUM('[2]P&L Prices'!B1:B9)+[2]Rates!C3");
+}
+
+#[test]
+fn references_into_linked_workbooks_keep_their_position_and_size() {
+    use gridcraft_model::{ExternalBook, ExternalSheet};
+    let mut t = T::new();
+    // Data!A1:B6: a header row, then items a..e priced 10..14.
+    let mut cells = vec![(c("A1"), Value::text("Item")), (c("B1"), Value::text("Price"))];
+    for (i, item) in ["a", "b", "c", "d", "e"].into_iter().enumerate() {
+        cells.push((CellRef::new(i as u32 + 1, 0), Value::text(item)));
+        cells.push((CellRef::new(i as u32 + 1, 1), Value::Number(10.0 + i as f64)));
+    }
+    cells.sort_by_key(|(p, _)| *p);
+    t.wb.external_books =
+        vec![ExternalBook { sheets: vec![ExternalSheet { name: "Data".into(), cells, refresh_error: false }], names: vec![], ..Default::default() }]
+            .into();
+    // `@` takes the cell on the formula's row (or column), as for this workbook's references.
+    for at in ["D2", "D3", "D4", "D5", "D6"] {
+        t.set(at, "=@[1]Data!B:B");
+    }
+    assert_eq!([t.num("D2"), t.num("D3"), t.num("D4"), t.num("D5"), t.num("D6")], [10.0, 11.0, 12.0, 13.0, 14.0]);
+    t.set("F4", "=@[1]Data!B3:B6");
+    t.set("F9", "=@[1]Data!B3:B6");
+    t.set("B10", "=@[1]Data!A1:B1");
+    assert_eq!((t.num("F4"), t.get("F9"), t.get("B10")), (12.0, Value::Error(CellError::Value), Value::text("Price")));
+    // The reference keeps the size written, past the last saved cell.
+    t.set("G1", "=ROWS([1]Data!A:A)");
+    t.set("G2", "=ROWS([1]Data!A1:A100000)");
+    t.set("G3", "=COLUMNS([1]Data!1:1)");
+    t.set("G4", "=INDEX([1]Data!B:B,4)");
+    t.set("G5", "=INDEX([1]Data!A:A,10)");
+    t.set("G6", "=SUM([1]Data!B:B)+VLOOKUP(\"c\",[1]Data!A:B,2,FALSE)");
+    t.set("G7", "=ISREF([1]Data!B2)");
+    assert_eq!(
+        (t.num("G1"), t.num("G2"), t.num("G3"), t.num("G4"), t.num("G5"), t.num("G6"), t.get("G7")),
+        (1_048_576.0, 100_000.0, 16_384.0, 12.0, 0.0, 72.0, Value::Bool(true))
+    );
+    // INDIRECT reads another workbook only while it is open.
+    t.set("H1", "=INDIRECT(\"[1]Data!B2\")");
+    assert_eq!(t.get("H1"), Value::Error(CellError::Ref));
+}
+
+#[test]
+fn offset_refuses_a_base_in_a_linked_workbook() {
+    use gridcraft_model::{ExternalBook, ExternalSheet};
+    let mut t = T::new();
+    // Curve!D8:D10 = 37 and Backup!D38 = 39: the saved link has every cell OFFSET would read,
+    // but Excel takes the ISERROR branch while the source workbook is closed (enron
+    // "West NatGas Prices 1031", PowerPrices!D9).
+    let curve = (8..=10).map(|r| (CellRef::new(r - 1, 3), Value::Number(37.0))).collect();
+    let backup = vec![(c("D38"), Value::Number(39.0))];
+    t.wb.external_books = vec![ExternalBook {
+        sheets: vec![
+            ExternalSheet { name: "Curve".into(), cells: curve, refresh_error: false },
+            ExternalSheet { name: "Backup".into(), cells: backup, refresh_error: false },
+        ],
+        names: vec![],
+        ..Default::default()
+    }]
+    .into();
+    t.set("A1", "=OFFSET([1]Curve!$D$6,2,0,3,1)");
+    t.set("A2", "=IF(ISERROR(AVERAGE(OFFSET([1]Curve!$D$6,2,0,3,1))),[1]Backup!$D$38,0)");
+    t.set("A3", "=SUM(OFFSET(B1,0,0,2,1))");
+    assert_eq!((t.get("A1"), t.num("A2"), t.num("A3")), (Value::Error(CellError::Value), 39.0, 0.0));
+}
+
+#[test]
+fn if_family_ranges_inside_lambdas_stay_references() {
+    // MAP/BYROW hand their LAMBDA ranges of this workbook: COUNTIF and SUMIF take them.
+    let mut t = T::new();
+    for (at, v) in [("E1", "1"), ("F1", "-2"), ("G1", "3"), ("E2", "-1"), ("F2", "5"), ("G2", "6")] {
+        t.set(at, v);
+    }
+    t.set("H1", "=BYROW(E1:G2,LAMBDA(r,COUNTIF(r,\">0\")))");
+    t.set("I1", "=MAP(E1:E2,LAMBDA(x,SUMIF(x,\">0\")))");
+    assert_eq!((t.num("H1"), t.num("H2"), t.num("I1"), t.num("I2")), (2.0, 2.0, 1.0, 0.0));
+}
+
 #[test]
 fn xlookup_returns_a_reference() {
     let mut t = T::new();

crates/calc/src/trimrange.rs

@@ -95,7 +95,7 @@ impl Evaluator<'_> {
                 if (h as u64) * (w as u64) > MAX_CELLS {
                     return Err(CellError::Num);
                 }
-                let values = self.host.range_values(a.sheet, part);
+                let values = self.block_values(a.sheet, part);
                 let ((r0, r1), (c0, c1)) = bounds(&values, w).ok_or(CellError::Calc)?;
                 let (h_all, w_all) = (a.range.height() as usize, a.range.width() as usize);
                 let (kr0, kr1) = keep(h_all, (r0, r1), rows);

crates/engine/src/catalog.rs

@@ -15,6 +15,7 @@ pub const CATALOG: &[(&str, &str, &str, &str)] = &[
     ("file.exportCsv", "File", "Export", "CSV"),
     ("file.exportHtml", "File", "Export", "Web Page"),
     ("file.properties", "File", "Info", "Properties"),
+    ("data.editLinks", "File", "Info", "Edit Links to Files"),
     ("file.options", "File", "Options", "Options"),
     // Home
     ("edit.paste", "Home", "Clipboard", "Paste"),
@@ -197,6 +198,7 @@ pub const CATALOG: &[(&str, &str, &str, &str)] = &[
     ("data.fromTableRange", "Data", "Get & Transform Data", "From Table/Range"),
     ("data.refreshAll", "Data", "Queries & Connections", "Refresh All"),
     ("data.queriesConnections", "Data", "Queries & Connections", "Queries & Connections"),
+    ("data.workbookLinks", "Data", "Queries & Connections", "Workbook Links"),
     ("data.stocks", "Data", "Data Types", "Stocks"),
     ("data.geography", "Data", "Data Types", "Geography"),
     ("data.sortAscending", "Data", "Sort & Filter", "Sort A to Z"),

crates/engine/src/cmd/data.rs

@@ -951,6 +951,9 @@ fn validation(s: &mut Session, p: &Json) -> Result<Json> {
         "custom" => ValidationKind::Custom,
         _ => ValidationKind::Any,
     };
+    for f in [str_param(p, "formula1"), str_param(p, "formula2")].into_iter().flatten() {
+        super::edit::refuse_linked_books(f)?;
+    }
     let dv = Validation {
         ranges: ranges.clone(),
         kind,