xlsx: drop stray worktree entries added by mistake

Every cell format record copied its font (name included) and built its
own copy of its number-format code, so many short records naming one
long font or code multiplied it in memory. Custom codes are now built
once and shared, and font names are cut to Excel's 31 characters.

apps/gridcraft-cli/src/check/calc.rs

@@ -31,41 +31,20 @@ fn is_volatile(e: &Expr, volatile_names: &HashSet<String>) -> bool {
 }
 
 /// Upper-cased defined names whose formula is volatile, directly or through other names.
-///
-/// Volatility flows backwards along name references: each name is parsed and walked once, and a
-/// worklist carries volatility from a name to the names that use it. Rescanning every name until
-/// nothing changes was quadratic: a file listing its names so that each pass marked only one more
-/// did one full pass per name.
 pub(super) fn volatile_names(wb: &Workbook) -> HashSet<String> {
+    let parsed: Vec<(String, Option<Expr>)> =
+        wb.names.iter().map(|n| (n.name.to_ascii_uppercase(), gridcraft_engine::formula::parse(&n.formula).ok())).collect();
     let mut set = HashSet::new();
-    // Upper-cased name -> the names whose formulas refer to it.
-    let mut users: HashMap<String, Vec<String>> = HashMap::new();
-    let mut queue = Vec::new();
-    let none = HashSet::new();
-    for n in &wb.names {
-        let name = n.name.to_ascii_uppercase();
-        let Ok(e) = gridcraft_engine::formula::parse(&n.formula) else { continue };
-        if is_volatile(&e, &none) {
-            if set.insert(name.clone()) {
-                queue.push(name.clone());
+    // Each round adds at least one name or stops, so `len + 1` rounds reach the fixed point.
+    for _ in 0..=parsed.len() {
+        let before = set.len();
+        for (name, e) in &parsed {
+            if !set.contains(name) && e.as_ref().is_some_and(|e| is_volatile(e, &set)) {
+                set.insert(name.clone());
             }
-            continue;
         }
-        let mut used = BTreeSet::new();
-        e.walk(&mut |x| {
-            if let Expr::Name(r) = x {
-                used.insert(r.to_ascii_uppercase());
-            }
-        });
-        for r in used {
-            users.entry(r).or_default().push(name.clone());
-        }
-    }
-    while let Some(v) = queue.pop() {
-        for user in users.remove(&v).unwrap_or_default() {
-            if set.insert(user.clone()) {
-                queue.push(user);
-            }
+        if set.len() == before {
+            break;
         }
     }
     set

apps/gridcraft-cli/src/check/tests.rs

@@ -178,28 +178,6 @@ fn volatile_names_propagate() {
     assert_eq!(check(&wb, &Options::default()).calc.volatile, 1);
 }
 
-#[test]
-fn volatile_names_propagate_through_a_long_chain_in_one_walk() {
-    // Chain0 uses Chain1, Chain1 uses Chain2, ... and only the last is volatile: listed in this order, a rescan
-    // until nothing changes marked one name per pass (quadratic). Every name in the chain is
-    // volatile; a name off the chain is not.
-    const LEN: usize = 5_000;
-    let mut wb = book(&[("A1", "=1", n(1.0))]);
-    let name =
-        |name: String, formula: String| gridcraft_engine::model::DefinedName { name, scope: None, formula, comment: String::new(), hidden: false };
-    for i in 0..LEN {
-        let formula = if i + 1 == LEN { "NOW()".to_string() } else { format!("Chain{}+1", i + 1) };
-        wb.names.push(name(format!("Chain{i}"), formula));
-    }
-    wb.names.push(name("Plain".into(), "Chain0*0+Other".into()));
-    wb.names.push(name("Other".into(), "1".into()));
-    let set = volatile_names(&wb);
-    assert!((0..LEN).all(|i| set.contains(&format!("CHAIN{i}"))));
-    assert!(set.contains("PLAIN"));
-    assert!(!set.contains("OTHER"));
-    assert_eq!(set.len(), LEN + 1);
-}
-
 #[test]
 fn round_trip_of_a_simple_book_is_clean() {
     let mut wb = book(&[("A1", "2", n(2.0)), ("B1", "=A1*3", n(6.0)), ("A2", "x", Value::text("x"))]);

crates/chart/src/raster.rs

@@ -7,12 +7,6 @@ use crate::{Prim, Rgba};
 /// Largest image we allocate (pixels).
 const MAX_PIXELS: u64 = 64 * 1024 * 1024;
 const SUB: usize = 4;
-/// Scan-conversion work one [`rasterize`] call may do: edge tests (an active edge at one
-/// sub-sample) plus covered pixels blended. Edges are only tested on the rows they cross, but a
-/// caller can still pass enough geometry to keep the rasteriser busy for minutes on a small
-/// image; once the allowance is spent the remaining fills are skipped. 2^28 is about a second,
-/// far beyond any chart.
-const MAX_SCAN_WORK: u64 = 1 << 28;
 
 type Path = Vec<Vec<[f32; 2]>>;
 
@@ -21,8 +15,6 @@ struct Canvas {
     h: usize,
     buf: Vec<u8>,
     acc: Vec<f32>,
-    /// Scan-conversion work left (see [`MAX_SCAN_WORK`]).
-    work: u64,
 }
 
 impl Canvas {
@@ -49,8 +41,7 @@ impl Canvas {
 
     /// Fills a multi-contour path with the even-odd rule.
     fn fill(&mut self, path: &Path, color: Rgba) {
-        // Each edge as [top y, bottom y, x0, y0, x1, y1].
-        let mut edges: Vec<[f32; 6]> = Vec::new();
+        let mut edges: Vec<[f32; 4]> = Vec::new();
         let (mut minx, mut miny, mut maxx, mut maxy) = (f32::INFINITY, f32::INFINITY, f32::NEG_INFINITY, f32::NEG_INFINITY);
         for c in path {
             if c.len() < 3 || !c.iter().all(|p| p[0].is_finite() && p[1].is_finite()) {
@@ -63,7 +54,7 @@ impl Canvas {
                 miny = miny.min(p[1]);
                 maxy = maxy.max(p[1]);
                 if p[1] != q[1] {
-                    edges.push([p[1].min(q[1]), p[1].max(q[1]), p[0], p[1], q[0], q[1]]);
+                    edges.push([p[0], p[1], q[0], q[1]]);
                 }
             }
         }
@@ -81,26 +72,8 @@ impl Canvas {
         if self.acc.len() < bw + 1 {
             self.acc.resize(bw + 1, 0.0);
         }
-        // Active-edge list: edges join when the scan reaches their top and leave past their
-        // bottom, so each row tests only the edges crossing it instead of every edge.
-        edges.sort_by(|a, b| a[0].total_cmp(&b[0]));
-        let mut pending = edges.iter().peekable();
-        let mut active: Vec<[f32; 6]> = Vec::new();
         let mut xs: Vec<f32> = Vec::new();
         for py in y0..y1 {
-            while let Some(e) = pending.next_if(|e| e[0] < py as f32 + 1.0) {
-                active.push(*e);
-            }
-            active.retain(|e| e[1] > py as f32);
-            if active.is_empty() {
-                continue;
-            }
-            let tests = (active.len() * SUB) as u64;
-            if tests > self.work {
-                self.work = 0;
-                return;
-            }
-            self.work -= tests;
             for v in self.acc.iter_mut().take(bw) {
                 *v = 0.0;
             }
@@ -108,9 +81,10 @@ impl Canvas {
             for s in 0..SUB {
                 let sy = py as f32 + (s as f32 + 0.5) / SUB as f32;
                 xs.clear();
-                for e in &active {
-                    if sy >= e[0] && sy < e[1] {
-                        xs.push(e[2] + (sy - e[3]) * (e[4] - e[2]) / (e[5] - e[3]));
+                for e in &edges {
+                    let (ya, yb) = if e[1] < e[3] { (e[1], e[3]) } else { (e[3], e[1]) };
+                    if sy >= ya && sy < yb {
+                        xs.push(e[0] + (sy - e[1]) * (e[2] - e[0]) / (e[3] - e[1]));
                     }
                 }
                 xs.sort_by(f32::total_cmp);
@@ -136,7 +110,6 @@ impl Canvas {
             if !any {
                 continue;
             }
-            self.work = self.work.saturating_sub(bw as u64);
             for px in x0..x1 {
                 let cov = self.acc.get(px - x0).copied().unwrap_or(0.0);
                 if cov > 0.0 {
@@ -239,7 +212,7 @@ pub fn rasterize(prims: &[Prim], w: u32, h: u32, background: Rgba) -> Vec<u8> {
     for _ in 0..w * h {
         buf.extend_from_slice(&background);
     }
-    let mut cv = Canvas { w, h, buf, acc: Vec::new(), work: MAX_SCAN_WORK };
+    let mut cv = Canvas { w, h, buf, acc: Vec::new() };
     for p in prims {
         match p {
             Prim::Rect { x, y, w, h, fill, stroke, radius } => {
@@ -301,31 +274,6 @@ pub fn rasterize(prims: &[Prim], w: u32, h: u32, background: Rgba) -> Vec<u8> {
 mod tests {
     use super::*;
 
-    /// Security: each row tests only the edges crossing it. A polygon of 100,000 tiny edges over
-    /// 4,000 rows tested every edge at every sub-sample of every row (1.6 billion tests).
-    #[test]
-    fn many_short_edges_scan_only_their_rows() {
-        let mut pts: Vec<[f32; 2]> = (0..100_000).map(|i| [if i % 2 == 0 { 0.0 } else { 0.5 }, i as f32 * 0.04]).collect();
-        pts.push([2.0, 4_000.0]);
-        pts.push([2.0, 0.0]);
-        let img = rasterize(&[Prim::Polygon { pts, fill: [255, 0, 0, 255], stroke: None }], 2, 4_000, [0, 0, 0, 0]);
-        // The right-hand pixel of every row is inside the polygon.
-        assert_eq!(img.get(4..8), Some(&[255, 0, 0, 255][..]));
-        assert_eq!(img.get(4 * (2 * 3_999 + 1)..4 * (2 * 3_999 + 2)), Some(&[255, 0, 0, 255][..]));
-    }
-
-    /// Security: scan conversion stops once the call's work allowance is spent.
-    #[test]
-    fn fills_stop_when_the_work_allowance_is_spent() {
-        let square = vec![vec![[0.0, 0.0], [4.0, 0.0], [4.0, 4.0], [0.0, 4.0]]];
-        let mut cv = Canvas { w: 4, h: 4, buf: vec![0; 64], acc: Vec::new(), work: 2 * SUB as u64 * 4 + 16 };
-        cv.fill(&square, [255; 4]);
-        assert!(cv.buf.iter().all(|&b| b == 255));
-        cv.buf = vec![0; 64];
-        cv.fill(&square, [255; 4]);
-        assert!(cv.buf.iter().all(|&b| b == 0));
-    }
-
     #[test]
     fn dashed_geometry_stays_within_the_dash_budget() {
         // Forty very long dashed lines, each allowed 10_000 dashes per segment: before the

crates/chart/src/render/lines.rs

@@ -136,13 +136,7 @@ pub(super) fn decimate_area(top: Vec<[f32; 2]>, base: Vec<[f32; 2]>, max: usize)
 
 /// Draws a polyline split at gaps (`None`), decimated when long. With `smooth` (the plot box),
 /// each run is interpolated with a Catmull-Rom spline so the line curves through the data points.
-///
-/// The points interpolation adds are budgeted across all the runs of the line, not per run:
-/// short runs between gaps escape decimation, and 100 sub-segments each would turn a
-/// 100,000-point series of three-point runs into millions of points. Past the budget the
-/// remaining runs are drawn through their data points only.
 pub(super) fn draw_runs(ctx: &mut Ctx, pts: &[Option<[f32; 2]>], color: Rgba, width: f32, smooth: Option<Bx>) {
-    let mut budget = MAX_LINE_PTS * 2;
     let mut run: Vec<[f32; 2]> = Vec::new();
     for p in pts.iter().chain(std::iter::once(&None)) {
         match p {
@@ -151,11 +145,7 @@ pub(super) fn draw_runs(ctx: &mut Ctx, pts: &[Option<[f32; 2]>], color: Rgba, wi
                 if run.len() >= 2 {
                     let r = decimate(std::mem::take(&mut run), MAX_LINE_PTS);
                     let r = match smooth {
-                        Some(plot) => {
-                            let r = smooth_run(r, plot, budget);
-                            budget = budget.saturating_sub(r.len());
-                            r
-                        }
+                        Some(plot) => smooth_run(r, plot),
                         None => r,
                     };
                     ctx.line(r, color, width);
@@ -168,15 +158,15 @@ pub(super) fn draw_runs(ctx: &mut Ctx, pts: &[Option<[f32; 2]>], color: Rgba, wi
 }
 
 /// Catmull-Rom spline through `pts`: every segment gets the same number of sub-segments (up to
-/// 100), chosen so the whole curve stays within `cap` points (one per data point when `cap` is
-/// smaller than that). Endpoints are
+/// 100), chosen so the whole curve stays within `MAX_LINE_PTS * 2` points. Endpoints are
 /// duplicated so the curve passes through the first and last points, and the curve is clamped
 /// to the `plot` box (a spline overshoots its data near sharp turns).
-fn smooth_run(pts: Vec<[f32; 2]>, plot: Bx, cap: usize) -> Vec<[f32; 2]> {
+fn smooth_run(pts: Vec<[f32; 2]>, plot: Bx) -> Vec<[f32; 2]> {
     let n = pts.len();
     if n < 3 {
         return pts;
     }
+    let cap = MAX_LINE_PTS * 2;
     let steps = (cap / n).clamp(1, 100);
     let mut out: Vec<[f32; 2]> = Vec::with_capacity(n.saturating_mul(steps).min(cap) + 1);
     let at = |i: isize| -> [f32; 2] {
@@ -229,7 +219,7 @@ mod smooth_tests {
     fn long_runs_are_smoothed_uniformly_within_the_cap() {
         let plot = Bx { x: 0.0, y: 0.0, w: 3000.0, h: 100.0 };
         let pts: Vec<[f32; 2]> = (0..1500).map(|i| [i as f32 * 2.0, if i % 2 == 0 { 20.0 } else { 80.0 }]).collect();
-        let out = smooth_run(pts, plot, MAX_LINE_PTS * 2);
+        let out = smooth_run(pts, plot);
         assert!(out.len() <= MAX_LINE_PTS * 2 + 1, "{}", out.len());
         // Two sub-segments per segment all the way to the end, not 100 each and then a straight tail.
         assert_eq!(out.len(), 1499 * 2 + 1);
@@ -241,29 +231,11 @@ mod smooth_tests {
         let plot = Bx { x: 0.0, y: 10.0, w: 300.0, h: 100.0 };
         // A step right at the plot edges: Catmull-Rom overshoots past both.
         let pts = vec![[0.0, 110.0], [100.0, 110.0], [110.0, 10.0], [200.0, 10.0], [300.0, 10.0]];
-        let out = smooth_run(pts, plot, MAX_LINE_PTS * 2);
+        let out = smooth_run(pts, plot);
         assert!(out.len() > 5);
         assert!(out.iter().all(|p| (0.0..=300.0).contains(&p[0]) && (10.0..=110.0).contains(&p[1])));
     }
 
-    /// Security: smoothing budgets its added points across every run of a line. A series of
-    /// three-point runs between gaps used to get 100 sub-segments per run, 67 times its data.
-    #[test]
-    fn gap_separated_runs_share_one_smoothing_budget() {
-        let plot = Bx { x: 0.0, y: 0.0, w: 1e6, h: 100.0 };
-        let pts: Vec<Option<[f32; 2]>> =
-            (0..100_000).map(|i| if i % 4 == 3 { None } else { Some([i as f32, if i % 2 == 0 { 20.0 } else { 80.0 }]) }).collect();
-        let m = crate::ApproxMeasure;
-        let mut ctx = Ctx { out: Vec::new(), m: &m };
-        draw_runs(&mut ctx, &pts, WHITE, 1.0, Some(plot));
-        let total: usize = ctx.out.iter().map(|p| if let Prim::Line { pts, .. } = p { pts.len() } else { 0 }).sum();
-        // 75,000 data points, plus at most the budget added by interpolation.
-        assert!(total <= 75_000 + MAX_LINE_PTS * 2, "{total}");
-        assert_eq!(ctx.out.len(), 25_000);
-        // The first runs are still smoothed.
-        assert!(matches!(ctx.out.first(), Some(Prim::Line { pts, .. }) if pts.len() > 3));
-    }
-
     #[test]
     fn decimate_area_preserves_paired_vertical_strips() {
         let top: Vec<[f32; 2]> = (0..1000).map(|i| [i as f32 * 0.25, ((i * 37) % 100) as f32]).collect();

crates/chart/src/resolve.rs

@@ -133,46 +133,6 @@ fn value_text(v: &Value) -> String {
     }
 }
 
-/// Characters kept of one category label: an axis label never shows more (labels are fitted to
-/// the axis), and copying more only costs memory.
-const MAX_LABEL_CHARS: usize = 255;
-/// Bytes of category label text kept per series. One long text broadcast by a short formula
-/// (`IF(SEQUENCE(100000), long_text)`) is a single shared value, but turning every element into
-/// its own label copied it 100,000 times (gigabytes). Labels past the budget are empty.
-const MAX_CATEGORY_BYTES: usize = 8 << 20;
-
-/// At most [`MAX_LABEL_CHARS`] characters and `room` bytes of `s`, cut at a character boundary.
-fn clip_label(s: &str, room: usize) -> String {
-    let mut end = 0;
-    for (n, (i, c)) in s.char_indices().enumerate() {
-        if n >= MAX_LABEL_CHARS || i + c.len_utf8() > room {
-            break;
-        }
-        end = i + c.len_utf8();
-    }
-    s.get(..end).unwrap_or_default().to_string()
-}
-
-/// The label of category `i` (value `v`) in at most `room` bytes: formatted with its source
-/// cell's number format when it is a number.
-fn category_label(wb: &Workbook, src: Option<(&gridcraft_model::Sheet, RangeRef)>, i: usize, v: &Value, room: usize) -> String {
-    if let (Some((s, r)), Value::Number(_)) = (src, v) {
-        let w = r.width().max(1) as usize;
-        let at = r.start.offset((i / w) as i64, (i % w) as i64);
-        if let Some(c) = at {
-            let code = &wb.styles.get(s.style_id(c)).num_fmt.0;
-            if !code.eq_ignore_ascii_case("general") {
-                return clip_label(&format_value(v, &NumberFormat::parse_cached(code), wb.date_system).text, room);
-            }
-        }
-    }
-    // Text is clipped before it is copied: the source may be one long shared string.
-    match v {
-        Value::Text(t) => clip_label(t, room),
-        _ => clip_label(&value_text(v), room),
-    }
-}
-
 /// Category labels, formatted with each source cell's number format (dates, currency…), and
 /// the outer levels of a multi-level axis: a category range wider than a column of values (or
 /// taller than a row of values) groups its innermost labels, year beside month. Each outer level
@@ -181,14 +141,21 @@ fn category_table(wb: &Workbook, sheet: usize, formula: &str, values: &str) -> (
     let vals = eval_list(wb, sheet, formula);
     let cells: Option<(usize, RangeRef)> = parse_ref(wb, sheet, formula);
     let src = cells.and_then(|(sh, r)| wb.sheet(sh).map(|s| (s, r)));
-    let mut room = MAX_CATEGORY_BYTES;
     let texts: Vec<String> = vals
         .iter()
         .enumerate()
         .map(|(i, v)| {
-            let label = category_label(wb, src, i, v, room);
-            room = room.saturating_sub(label.len());
-            label
+            if let (Some((s, r)), Value::Number(_)) = (src, v) {
+                let w = r.width().max(1) as usize;
+                let at = r.start.offset((i / w) as i64, (i % w) as i64);
+                if let Some(c) = at {
+                    let code = &wb.styles.get(s.style_id(c)).num_fmt.0;
+                    if !code.eq_ignore_ascii_case("general") {
+                        return format_value(v, &NumberFormat::parse_cached(code), wb.date_system).text;
+                    }
+                }
+            }
+            value_text(v)
         })
         .collect();
     let Some((_, r)) = src else { return (texts, vec![]) };
@@ -309,23 +276,3 @@ pub fn resolve(wb: &Workbook, sheet: usize, chart: &Chart) -> ChartData {
     let palette = default_palette(&wb.theme, n.min(PALETTE_CYCLE));
     ChartData { categories, category_levels, series, palette }
 }
-
-#[cfg(test)]
-mod label_budget_tests {
-    use gridcraft_model::Workbook;
-
-    /// Security: category labels are clipped before they are copied, with one byte budget per
-    /// series. A formula broadcasting one long text to 100,000 categories used to copy it
-    /// 100,000 times (3.3 GB).
-    #[test]
-    fn category_labels_share_one_byte_budget() {
-        let wb = Workbook::new();
-        let (texts, _) = super::category_table(&wb, 0, r#"=IF(SEQUENCE(100000),REPT("x",32767))"#, "");
-        assert_eq!(texts.len(), 100_000);
-        assert_eq!(texts.first().map(String::len), Some(super::MAX_LABEL_CHARS));
-        assert!(texts.iter().map(String::len).sum::<usize>() <= super::MAX_CATEGORY_BYTES);
-        // Labels are cut at character boundaries.
-        assert_eq!(super::clip_label("aé", 2), "a");
-        assert_eq!(super::clip_label("aé", 3), "aé");
-    }
-}

crates/engine/src/cmd.rs

@@ -459,11 +459,8 @@ pub(crate) const TOUCH_LOG_LIMIT: usize = 1_000_000;
 pub(crate) const PROTECTED: &str = "The cell or chart you're trying to change is on a protected sheet.";
 
 /// Refuses an edit that changed what a locked cell on a protected sheet holds (its value or
-/// formula), or that unlocked it, whichever command made it. Sheets are matched by name, so
-/// moving, renaming or deleting a sheet isn't an edit of its cells. A sort or duplicate removal
-/// that moves an unlocked cell with equal content onto a locked one changes no content but would
-/// leave the cell editable, so the effective lock (row and column formats included) is compared
-/// as well.
+/// formula), whichever command made it. Sheets are matched by name, so moving, renaming or
+/// deleting a sheet isn't an edit of its cells.
 fn check_protection(old: &Workbook, new: &Workbook, unlocked: &[(String, String)]) -> Result<()> {
     for sh in &old.sheets {
         if !sh.is_protected() {
@@ -474,8 +471,7 @@ fn check_protection(old: &Workbook, new: &Workbook, unlocked: &[(String, String)
             continue;
         }
         for c in sh.cells.diff(&after.cells) {
-            let unlocked_now = !new.styles.get(after.style_id(c)).protection.locked;
-            if (unlocked_now || !same_content(sh.cell(c), after.cell(c)))
+            if !same_content(sh.cell(c), after.cell(c))
                 && old.styles.get(sh.style_id(c)).protection.locked
                 && let Some(m) = locked_cell_error(sh, c, unlocked)
             {

crates/engine/src/cmd/sheet.rs

@@ -398,10 +398,10 @@ fn move_columns(s: &mut Session, p: &Json) -> Result<Json> {
     {
         return Err(EngineError::Other("To prevent possible loss of data, columns cannot be shifted off of the worksheet.".into()));
     }
-    // The checks must authorize the sheet this command modifies, not whatever sheet is active:
-    // both get the index `target_sheet` resolved (from `sheet`, or a `Sheet!` range or cell).
-    check_lines_protection(s, &json!({"cols": RangeRef::cols(before, before).a1(), "sheet": sheet}), Axis::Cols, before, count, true)?;
-    check_lines_protection(s, &json!({"cols": RangeRef::cols(from, end - 1).a1(), "sheet": sheet}), Axis::Cols, from, count, false)?;
+    // The checks must authorize the sheet this command modifies (`target_sheet`), not whatever
+    // sheet is active: both carry the command's own `sheet` parameter on.
+    check_lines_protection(s, &json!({"cols": RangeRef::cols(before, before).a1(), "sheet": p.get("sheet")}), Axis::Cols, before, count, true)?;
+    check_lines_protection(s, &json!({"cols": RangeRef::cols(from, end - 1).a1(), "sheet": p.get("sheet")}), Axis::Cols, from, count, false)?;
 
     let moved_from = if before <= from { from + count } else { from };
     if moved_from.checked_add(count).is_none_or(|end| end > MAX_COLS) {

crates/engine/src/tests.rs

@@ -5297,42 +5297,6 @@ fn move_columns_checks_the_protection_of_the_named_sheet() {
     assert_eq!(v(&s, "A1"), Value::text("A"));
 }
 
-#[test]
-fn move_columns_checks_the_protection_of_a_sheet_named_by_its_range() {
-    // A `Sheet!` range or cell picks the sheet the move modifies; the protection checks must
-    // authorize that sheet too, not the active one.
-    let mut s = s();
-    s.execute("home.insertSheet", json!({"name": "P"})).unwrap();
-    s.execute("range.setValues", json!({"range": "A1", "values": [[1, 2, 3, 4]]})).unwrap();
-    s.execute("review.protectSheet", json!({})).unwrap();
-    s.execute("sheet.activate", json!({"sheet": 0})).unwrap();
-    for key in ["range", "cell"] {
-        let err = s.execute("sheet.moveColumns", json!({key: "P!A1", "cols": "B:C", "before": 4})).expect_err("moving columns on a protected sheet");
-        assert!(err.to_string().contains("protected"), "{err}");
-    }
-    let d = s.doc().unwrap();
-    let sh = &d.wb.sheets[d.wb.sheet_index("P").unwrap()];
-    let pv: Vec<Value> = (0..4).map(|c| sh.value(CellRef::new(0, c))).collect();
-    assert_eq!(pv, vec![Value::number(1.0), Value::number(2.0), Value::number(3.0), Value::number(4.0)]);
-}
-
-#[test]
-fn sorting_cannot_unlock_a_locked_cell_by_moving_equal_content_onto_it() {
-    // An unlocked 2 sorted onto a locked 2 leaves the content as it was, but would make the cell
-    // editable; the sort is refused instead.
-    let mut s = s();
-    s.execute("range.setValues", json!({"range": "A1", "values": [[2], [2], [1]]})).unwrap();
-    s.execute("home.lockCell", json!({"range": "A1", "on": false})).unwrap();
-    s.execute("home.lockCell", json!({"range": "A3", "on": false})).unwrap();
-    s.execute("review.protectSheet", json!({"sort": true})).unwrap();
-    let before = s.doc().unwrap().wb.clone();
-    let err =
-        s.execute("data.sort", json!({"range": "A1:A3", "header": false, "keys": [{"column": "A", "order": "asc"}]})).expect_err("sort unlocking A2");
-    assert!(err.to_string().contains("protected sheet"), "{err}");
-    assert_eq!(*s.doc().unwrap().wb, *before);
-    assert!(s.execute("cell.set", json!({"cell": "A2", "input": "9"})).is_err(), "A2 stays locked");
-}
-
 #[test]
 fn a_script_cannot_switch_windows() {
     // Stored scripts are scoped to their workbook: a step that activates another window would

crates/xlsx/src/styles.rs

@@ -59,11 +59,14 @@ fn bool_prop(e: &El, name: &str) -> bool {
 
 const DEFAULT_FONT_FAMILY: u8 = 2;
 const MAX_FONT_FAMILY: u8 = 14;
+/// Longest font name kept, in characters (Excel's own limit). Every cell format copies its
+/// font, so a long name repeated by many formats would otherwise multiply in memory.
+const MAX_FONT_NAME: usize = 31;
 
 pub fn read_font(e: &El, palette: &[u32]) -> Font {
     let mut f = Font::default();
     if let Some(n) = e.child("name").or_else(|| e.child("rFont")).and_then(|n| n.attr("val")) {
-        f.name = n.to_string();
+        f.name = n.chars().take(MAX_FONT_NAME).collect();
     }
     if let Some(sz) = e.child("sz").and_then(|s| s.attr_f64("val")) {
         f.size = sz.clamp(1.0, 409.0) as f32;
@@ -277,14 +280,14 @@ fn read_protection(p: &El) -> Protection {
     Protection { locked: p.flag("locked", true), hidden: p.flag("hidden", false) }
 }
 
-fn num_fmt_code(id: u32, custom: &HashMap<u32, String>) -> NumFmt {
+fn num_fmt_code(id: u32, custom: &HashMap<u32, NumFmt>) -> NumFmt {
     if let Some(c) = custom.get(&id) {
-        return NumFmt::new(c);
+        return c.clone();
     }
     NumFmt::new(builtin_format(id).unwrap_or("General"))
 }
 
-fn read_xf(xf: &El, fonts: &[Font], fills: &[Fill], borders: &[Borders], fmts: &HashMap<u32, String>, checkboxes: &[bool]) -> Style {
+fn read_xf(xf: &El, fonts: &[Font], fills: &[Fill], borders: &[Borders], fmts: &HashMap<u32, NumFmt>, checkboxes: &[bool]) -> Style {
     let mut s = Style::default();
     if let Some(f) = xf.attr_u32("fontId").and_then(|i| fonts.get(i as usize)) {
         s.font = f.clone();
@@ -336,6 +339,8 @@ pub fn read_styles(root: &El, checkboxes: &[bool], minor_font: &str) -> StylesIn
             }
         }
     }
+    // One shared copy of each custom code, which every format using it points to.
+    let shared_fmts: HashMap<u32, NumFmt> = fmts.iter().map(|(id, code)| (*id, NumFmt::new(code))).collect();
     // The scheme link only means something on a font in the body face; elsewhere it stays as a new font has it.
     let body_font = |e: &El| {
         let mut f = read_font(e, &palette);
@@ -345,10 +350,14 @@ pub fn read_styles(root: &El, checkboxes: &[bool], minor_font: &str) -> StylesIn
     let fonts: Vec<Font> = root.child("fonts").map(|f| f.kids("font").map(body_font).collect()).unwrap_or_default();
     let fills: Vec<Fill> = root.child("fills").map(|f| f.kids("fill").map(|e| read_fill(e, &palette, false)).collect()).unwrap_or_default();
     let borders: Vec<Borders> = root.child("borders").map(|f| f.kids("border").map(|e| read_border(e, &palette)).collect()).unwrap_or_default();
-    let xfs =
-        root.child("cellXfs").map(|x| x.kids("xf").map(|xf| read_xf(xf, &fonts, &fills, &borders, &fmts, checkboxes)).collect()).unwrap_or_default();
-    let style_xfs: Vec<Style> =
-        root.child("cellStyleXfs").map(|x| x.kids("xf").map(|xf| read_xf(xf, &fonts, &fills, &borders, &fmts, &[])).collect()).unwrap_or_default();
+    let xfs = root
+        .child("cellXfs")
+        .map(|x| x.kids("xf").map(|xf| read_xf(xf, &fonts, &fills, &borders, &shared_fmts, checkboxes)).collect())
+        .unwrap_or_default();
+    let style_xfs: Vec<Style> = root
+        .child("cellStyleXfs")
+        .map(|x| x.kids("xf").map(|xf| read_xf(xf, &fonts, &fills, &borders, &shared_fmts, &[])).collect())
+        .unwrap_or_default();
     let mut named = Vec::new();
     if let Some(cs) = root.child("cellStyles") {
         for c in cs.kids("cellStyle") {
@@ -359,12 +368,12 @@ pub fn read_styles(root: &El, checkboxes: &[bool], minor_font: &str) -> StylesIn
             }
         }
     }
-    let dxfs = root.child("dxfs").map(|d| d.kids("dxf").map(|x| read_dxf(x, &palette, &fmts)).collect()).unwrap_or_default();
+    let dxfs = root.child("dxfs").map(|d| d.kids("dxf").map(|x| read_dxf(x, &palette, &shared_fmts)).collect()).unwrap_or_default();
     StylesIn { xfs, dxfs, palette, named, num_fmts: fmts }
 }
 
 /// One differential format (`dxf`): the style it sets over a cell's own.
-fn read_dxf(x: &El, palette: &[u32], fmts: &HashMap<u32, String>) -> Style {
+fn read_dxf(x: &El, palette: &[u32], fmts: &HashMap<u32, NumFmt>) -> Style {
     let mut s = Style::default();
     if let Some(e) = x.child("font") {
         let f = read_font(e, palette);

crates/xlsx/src/tests/malformed.rs

@@ -385,3 +385,22 @@ fn outline_summary_directions_round_trip() {
     let xml = String::from_utf8(crate::package::Package::open(&bytes).unwrap().read("xl/worksheets/sheet1.xml").unwrap().unwrap()).unwrap();
     assert!(!xml.contains("outlinePr"), "{xml}");
 }
+
+/// Many cell formats naming one long font and one long custom number format: the code is shared
+/// by every format and the font name is cut to Excel's 31 characters, so neither is copied per
+/// format.
+#[test]
+fn cell_formats_share_their_number_format_and_keep_short_font_names() {
+    let xml = format!(
+        r#"<styleSheet><numFmts><numFmt numFmtId="164" formatCode="{}"/></numFmts><fonts><font><name val="{}"/></font></fonts><cellXfs>{}</cellXfs></styleSheet>"#,
+        "0".repeat(100_000),
+        "F".repeat(100_000),
+        r#"<xf numFmtId="164" fontId="0"/>"#.repeat(20_000)
+    );
+    let root = crate::xml::parse(xml.as_bytes()).unwrap();
+    let st = crate::styles::read_styles(&root, &[], "Calibri");
+    assert_eq!(st.xfs.len(), 20_000);
+    assert!(st.xfs.iter().all(|s| std::sync::Arc::ptr_eq(&s.num_fmt.0, &st.xfs[0].num_fmt.0)));
+    assert_eq!(st.xfs[0].num_fmt.as_str().len(), 100_000);
+    assert!(st.xfs.iter().all(|s| s.font.name.chars().count() == 31));
+}