Forecast Sheet: count hindcast rows against the work limit

MAX_WORK bounded history rows x forecast rows, but a Forecast Start
inside the history adds a hindcast row for every history point after
it, each holding the same ETS formulas that refit the model over the
history before the start. Those rows were not counted, so a start in
the middle of 10,000 rows of history built millions of uncharged
model fits per recalculation.

The forecast row cap is now computed from the rows the model is fit
to, after subtracting the hindcast rows; a start so early that the
hindcast alone passes the limit is refused, and the default number of
periods stays within the cap.

crates/chart/src/render/cartesian.rs

@@ -1,6 +1,6 @@
 use super::frame::{Bx, CatAxis, ValAxis, frame, on, value_range};
 use super::legend::{cat_label, plot_kind};
-use super::lines::{decimate_area, draw_markers, draw_runs};
+use super::lines::{decimate, draw_markers, draw_runs};
 use super::trend::{draw_trend_labels, draw_trendlines, max_backward, max_forward, max_forward_slots, supports_trendline};
 use super::{
     Chart, ChartData, ChartKind, Ctx, Fmt, HAlign, LABEL_SIZE, MAX_CATS, MAX_LABELS, MAX_LINE_PTS, MAX_MARKERS, Prim, Scale, SeriesData, TEXT,
@@ -268,7 +268,10 @@ pub(super) fn cartesian(ctx: &mut Ctx, chart: &Chart, data: &ChartData, area: Bx
                             base = vec![[b[0] - cw * 0.3, b[1]], [b[0] + cw * 0.3, b[1]]];
                         }
                     }
-                    let poly = decimate_area(top, base, MAX_LINE_PTS * 2);
+                    let top = decimate(top, MAX_LINE_PTS * 2);
+                    let base = decimate(base, MAX_LINE_PTS * 2);
+                    let mut poly = top;
+                    poly.extend(base.into_iter().rev());
                     if poly.len() >= 3 {
                         ctx.out.push(Prim::Polygon { pts: poly, fill: s.color, stroke: None });
                     }

crates/chart/src/render/lines.rs

@@ -54,86 +54,6 @@ pub(super) fn decimate(pts: Vec<[f32; 2]>, max: usize) -> Vec<[f32; 2]> {
     out
 }
 
-/// Decimates the top and baseline of an area chart together at the same horizontal indices so
-/// `area_mesh`'s paired vertical-strip topology (`pts[i]` ↔ `pts[2n - 1 - i]`) is preserved.
-pub(super) fn decimate_area(top: Vec<[f32; 2]>, base: Vec<[f32; 2]>, max: usize) -> Vec<[f32; 2]> {
-    let n = top.len().min(base.len());
-    if n == 0 {
-        return Vec::new();
-    }
-    if n <= max {
-        let mut poly = top;
-        poly.truncate(n);
-        poly.extend(base.into_iter().take(n).rev());
-        return poly;
-    }
-    let mut cols: Vec<[usize; 6]> = Vec::new();
-    let mut keep = Vec::with_capacity(max * 2);
-    let mut i = 0;
-    while i < n {
-        let col = top[i][0].floor();
-        let (start, mut t_mn, mut t_mx, mut b_mn, mut b_mx) = (i, i, i, i, i);
-        let mut k = i + 1;
-        while k < n && top[k][0].floor() == col {
-            if top[k][1] < top[t_mn][1] {
-                t_mn = k;
-            }
-            if top[k][1] > top[t_mx][1] {
-                t_mx = k;
-            }
-            if base[k][1] < base[b_mn][1] {
-                b_mn = k;
-            }
-            if base[k][1] > base[b_mx][1] {
-                b_mx = k;
-            }
-            k += 1;
-        }
-        let entry = [start, t_mn, t_mx, b_mn, b_mx, k - 1];
-        cols.push(entry);
-        let mut idx = entry;
-        idx.sort_unstable();
-        let mut last = usize::MAX;
-        for ix in idx {
-            if ix != last {
-                keep.push(ix);
-                last = ix;
-            }
-        }
-        i = k;
-    }
-    if keep.len() > max * 4 {
-        let max_groups = (max * 4 / 6).max(1);
-        let group_size = cols.len().div_ceil(max_groups);
-        keep.clear();
-        for ch in cols.chunks(group_size) {
-            let start = ch[0][0];
-            let end = ch.last().map_or(start, |c| c[5]);
-            let t_mn = ch.iter().map(|c| c[1]).min_by(|&a, &b| top[a][1].total_cmp(&top[b][1])).unwrap_or(start);
-            let t_mx = ch.iter().map(|c| c[2]).max_by(|&a, &b| top[a][1].total_cmp(&top[b][1])).unwrap_or(start);
-            let b_mn = ch.iter().map(|c| c[3]).min_by(|&a, &b| base[a][1].total_cmp(&base[b][1])).unwrap_or(start);
-            let b_mx = ch.iter().map(|c| c[4]).max_by(|&a, &b| base[a][1].total_cmp(&base[b][1])).unwrap_or(start);
-            let mut idx = [start, t_mn, t_mx, b_mn, b_mx, end];
-            idx.sort_unstable();
-            let mut last = usize::MAX;
-            for ix in idx {
-                if ix != last {
-                    keep.push(ix);
-                    last = ix;
-                }
-            }
-        }
-    }
-    let mut poly = Vec::with_capacity(keep.len() * 2);
-    for &ix in &keep {
-        poly.push(top[ix]);
-    }
-    for &ix in keep.iter().rev() {
-        poly.push(base[ix]);
-    }
-    poly
-}
-
 /// 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.
 pub(super) fn draw_runs(ctx: &mut Ctx, pts: &[Option<[f32; 2]>], color: Rgba, width: f32, smooth: Option<Bx>) {
@@ -235,57 +155,4 @@ mod smooth_tests {
         assert!(out.len() > 5);
         assert!(out.iter().all(|p| (0.0..=300.0).contains(&p[0]) && (10.0..=110.0).contains(&p[1])));
     }
-
-    #[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();
-        let base: Vec<[f32; 2]> = (0..1000).map(|i| [i as f32 * 0.25, 100.0]).collect();
-        let poly = decimate_area(top, base, 64);
-        assert_eq!(poly.len() % 2, 0);
-        let half = poly.len() / 2;
-        for i in 0..half {
-            assert_eq!(poly[i][0], poly[poly.len() - 1 - i][0]);
-            assert_eq!(poly[poly.len() - 1 - i][1], 100.0);
-        }
-    }
-
-    #[test]
-    fn decimate_area_preserves_extrema_across_3000_columns() {
-        // 3,000 occupied pixel columns with 6 points per column (18,000 points total),
-        // where each column has distinct top and baseline extrema so the initial per-column
-        // index list exceeds `MAX_LINE_PTS * 2 * 4` (6,400).
-        let max = MAX_LINE_PTS * 2;
-        let mut top = Vec::with_capacity(18_000);
-        let mut base = Vec::with_capacity(18_000);
-        for col in 0..3_000 {
-            let y_top = [50.0, 20.0, 80.0, 50.0, 50.0, 50.0];
-            let y_base = [150.0, 150.0, 150.0, 120.0, 180.0, 150.0];
-            for s in 0..6 {
-                let x = col as f32 + s as f32 * 0.1;
-                top.push([x, y_top[s]]);
-                base.push([x, y_base[s]]);
-            }
-        }
-        // Plant sharp spikes on both top and baseline in interior columns.
-        top[777 * 6 + 1][1] = 1.0;
-        top[1999 * 6 + 2][1] = 99.0;
-        base[1234 * 6 + 3][1] = 101.0;
-        base[2501 * 6 + 4][1] = 199.0;
-
-        let poly = decimate_area(top, base, max);
-        assert_eq!(poly.len() % 2, 0);
-        let half = poly.len() / 2;
-        assert!(half <= max * 4, "retained {half} paired vertices, limit is {}", max * 4);
-        for i in 0..half {
-            assert_eq!(poly[i][0], poly[poly.len() - 1 - i][0]);
-        }
-        let top_kept = &poly[..half];
-        let base_kept = &poly[half..];
-        assert_eq!(top_kept.first().map(|p| p[0]), Some(0.0));
-        assert_eq!(top_kept.last().map(|p| p[0]), Some(2999.5));
-        assert!(top_kept.iter().any(|p| p[1] == 1.0), "top min spike preserved");
-        assert!(top_kept.iter().any(|p| p[1] == 99.0), "top max spike preserved");
-        assert!(base_kept.iter().any(|p| p[1] == 101.0), "base min spike preserved");
-        assert!(base_kept.iter().any(|p| p[1] == 199.0), "base max spike preserved");
-    }
 }

crates/core/src/addr.rs

@@ -188,12 +188,6 @@ impl RangeRef {
             end: CellRef::new(self.end.row.max(o.end.row), self.end.col.max(o.end.col)),
         }
     }
-    /// The top-left cell of a list of areas: the lowest row and the lowest column across all of
-    /// them, whatever order they are listed in. Excel writes the relative formulas of a
-    /// multi-area validation or conditional format for this cell. `None` for no areas.
-    pub fn top_left(ranges: &[RangeRef]) -> Option<CellRef> {
-        ranges.iter().copied().reduce(|a, b| a.union(&b)).map(|r| r.start)
-    }
     /// Row-major iterator over the cells. Callers must bound huge ranges themselves.
     pub fn iter(&self) -> impl Iterator<Item = CellRef> + '_ {
         let (r0, r1, c0, c1) = (self.start.row, self.end.row, self.start.col, self.end.col);
@@ -313,16 +307,6 @@ mod tests {
         Ok(())
     }
 
-    #[test]
-    fn top_left_spans_every_area_in_any_order() {
-        let areas: Vec<RangeRef> = ["H62:H68", "H26:H27", "H93:H95"].iter().filter_map(|a| RangeRef::parse(a)).collect();
-        assert_eq!(RangeRef::top_left(&areas), CellRef::parse("H26"));
-        // Lowest row and lowest column, even when they come from different areas.
-        let areas: Vec<RangeRef> = ["C5:D6", "E2", "B9"].iter().filter_map(|a| RangeRef::parse(a)).collect();
-        assert_eq!(RangeRef::top_left(&areas), CellRef::parse("B2"));
-        assert_eq!(RangeRef::top_left(&[]), None);
-    }
-
     #[test]
     fn sheet_quoting_follows_excel() {
         for quoted in [

crates/engine/src/cf.rs

@@ -244,7 +244,7 @@ impl CfCache {
         let v = sh.value(c);
         let no_stats = RuleStats::default();
         for (idx, cf) in rules {
-            let first = RangeRef::top_left(&cf.ranges).unwrap_or(c);
+            let first = cf.ranges.first().map(|r| r.start).unwrap_or(c);
             let st: &RuleStats = match stats_need(&cf.rule) {
                 Some(need) => &*self.stats.entry(idx).or_insert_with(|| RuleStats::build(sh, &cf.ranges, need)),
                 None => &no_stats,

crates/engine/src/cmd/data/tests.rs

@@ -480,45 +480,6 @@ fn a_list_typed_without_quotes_is_saved_as_a_quoted_list() {
     assert_eq!(sheet_xml(&reopened), xml, "a second save writes the same rules");
 }
 
-#[test]
-fn a_relative_list_source_is_read_from_the_cell_being_checked() {
-    // As in Excel, `=$B1:$B2` on A3:A4,A1:A2 is written for A1 (the top-left cell of all the
-    // areas) and lists B4:B5 at A4. It used to list B1:B2 in every cell.
-    let mut s = Session::new();
-    s.new_workbook();
-    s.execute("range.setValues", json!({"range": "B1:B5", "values": [["a"], ["b"], ["c"], ["d"], ["e"]]})).unwrap();
-    s.execute("data.validation", json!({"range": "A3:A4,A1:A2", "type": "list", "formula1": "=$B1:$B2"})).unwrap();
-    let wb = s.doc().unwrap().wb.clone();
-    let dv = wb.active().unwrap().validations[0].clone();
-    for (cell, items) in [("A1", ["a", "b"]), ("A2", ["b", "c"]), ("A3", ["c", "d"]), ("A4", ["d", "e"])] {
-        let at = CellRef::parse(cell).unwrap();
-        assert_eq!(list_items(&wb, 0, at, &dv), items, "{cell}");
-        for v in ["a", "b", "c", "d", "e"] {
-            assert_eq!(check_validation(&wb, 0, at, v).is_none(), items.contains(&v), "{cell} with {v}");
-        }
-    }
-}
-
-#[test]
-fn a_list_source_that_takes_in_the_cell_does_not_list_the_value_being_typed() {
-    // `=$A1:$A2` on A2:A3 is A1:A2 at A2 and A2:A3 at A3. The list is the one before the entry, as
-    // in Excel; a new value used to land in its own source and pass.
-    let mut s = Session::new();
-    s.new_workbook();
-    s.execute("range.setValues", json!({"range": "A1:A2", "values": [["x"], ["y"]]})).unwrap();
-    s.execute("data.validation", json!({"range": "A2:A3", "type": "list", "formula1": "=$A1:$A2"})).unwrap();
-    let wb = &s.doc().unwrap().wb;
-    for (cell, accepted, refused) in [("A2", &["x", "y"][..], &["new"][..]), ("A3", &["y"], &["x", "new"])] {
-        let at = CellRef::parse(cell).unwrap();
-        for v in accepted {
-            assert!(check_validation(wb, 0, at, v).is_none(), "{cell} refuses {v}");
-        }
-        for v in refused {
-            assert!(check_validation(wb, 0, at, v).is_some(), "{cell} accepts {v}");
-        }
-    }
-}
-
 #[test]
 fn a_rule_with_an_unknown_type_operator_or_error_style_is_refused() {
     // A typo used to give a rule that validates nothing (`type="none"`) or the wrong check,

crates/engine/src/cmd/data/validation.rs

@@ -38,18 +38,11 @@ fn subtract_range(r: RangeRef, cut: &RangeRef) -> Vec<RangeRef> {
 }
 
 /// Removes the cells of `cuts` from every validation, keeping the rest of each rule's ranges.
-/// When the rule's top-left cell goes, its relative formulas are rewritten for the new top-left
-/// cell, so the cells left keep checking the same cells.
 pub(in super::super) fn remove_validation_cells(validations: &mut Vec<Validation>, cuts: &[RangeRef]) {
     for dv in validations.iter_mut() {
-        let before = RangeRef::top_left(&dv.ranges);
         for cut in cuts {
             dv.ranges = dv.ranges.iter().flat_map(|r| subtract_range(*r, cut)).collect();
         }
-        if let (Some(from), Some(to)) = (before, RangeRef::top_left(&dv.ranges)) {
-            dv.f1 = move_rule_formula(&dv.f1, from, to);
-            dv.f2 = dv.f2.take().map(|f| move_rule_formula(&f, from, to));
-        }
     }
     validations.retain(|d| !d.ranges.is_empty());
 }
@@ -152,10 +145,8 @@ fn list_source(f: &str) -> String {
     format!("\"{}\"", t.replace('"', "\"\""))
 }
 
-/// List entries of a list validation (literal or from a range) for the cell `at`. A relative
-/// source is written for the rule's top-left cell and read from `at`, as in Excel (`=$B1:$B3` on
-/// A1:A9 lists B5:B7 at A5).
-pub fn list_items(wb: &Workbook, sheet: usize, at: CellRef, dv: &Validation) -> Vec<String> {
+/// List entries of a list validation (literal or from a range).
+pub fn list_items(wb: &Workbook, sheet: usize, dv: &Validation) -> Vec<String> {
     let f = dv.f1.trim();
     if is_literal_list(f) {
         // A quoted list is a string literal: `""` inside stands for one `"`.
@@ -165,8 +156,8 @@ pub fn list_items(wb: &Workbook, sheet: usize, at: CellRef, dv: &Validation) ->
         };
         return items.split(',').map(|x| x.trim().to_string()).filter(|x| !x.is_empty()).collect();
     }
-    let first = RangeRef::top_left(&dv.ranges).unwrap_or(at);
-    match gridcraft_calc::evaluate(wb, sheet, at, &formula_at(f, first, at)) {
+    let at = dv.ranges.first().map(|r| r.start).unwrap_or_default();
+    match gridcraft_calc::evaluate(wb, sheet, at, f) {
         Value::Array(a) => a.data.iter().filter(|v| !v.is_empty()).map(Value::display).collect(),
         v if !v.is_empty() && !v.is_error() => vec![v.display()],
         _ => vec![],
@@ -184,10 +175,9 @@ pub fn check_validation(wb: &Workbook, sheet: usize, at: CellRef, input: &str) -
         return None;
     }
     let v = gridcraft_core::parse::parse_input(input, wb.date_system).value;
-    // The formulas are written for the top-left cell of all the areas and see the value being entered,
+    // The formulas are written for the first cell of the range and see the value being entered,
     // as in Excel (a custom `=A1>10` on A1:A9 checks A5's new value at A5).
-    let first = RangeRef::top_left(&dv.ranges).unwrap_or(at);
-    let original = wb;
+    let first = dv.ranges.first().map(|r| r.start).unwrap_or(at);
     let entered;
     let wb = if sh.value(at) == v {
         wb
@@ -203,9 +193,7 @@ pub fn check_validation(wb: &Workbook, sheet: usize, at: CellRef, input: &str) -
     let eval = |f: &str| gridcraft_calc::evaluate(wb, sheet, at, &formula_at(f, first, at));
     let num = |f: &str| eval(f).to_number().ok();
     let ok = match dv.kind {
-        // The list is the one the dropdown showed before the entry, as in Excel: a source that takes
-        // in the cell itself (`=$A1:$A2` on A2:A3 is A2:A3 at A3) doesn't list the value being typed.
-        ValidationKind::List => list_items(original, sheet, at, dv).iter().any(|x| x.eq_ignore_ascii_case(input)),
+        ValidationKind::List => list_items(wb, sheet, dv).iter().any(|x| x.eq_ignore_ascii_case(input)),
         ValidationKind::Custom => eval(&dv.f1).to_bool().unwrap_or(false),
         ValidationKind::TextLength => {
             let n = input.chars().count() as f64;

crates/engine/src/cmd/edit/paste_special.rs

@@ -284,7 +284,7 @@ pub(super) fn paste_special(s: &mut Session, p: &Json) -> Result<Json> {
                 crate::cmd::data::remove_validation_cells(&mut sh.validations, &[RangeRef::new(dest, dest)]);
                 if let Some(mut dv) = rule {
                     // Relative references move with the rule, as pasted formulas do.
-                    let first = RangeRef::top_left(&dv.ranges).unwrap_or(sc);
+                    let first = dv.ranges.first().map_or(sc, |r| r.start);
                     dv.f1 = crate::cmd::data::move_rule_formula(&dv.f1, first, dest);
                     dv.f2 = dv.f2.map(|f| crate::cmd::data::move_rule_formula(&f, first, dest));
                     dv.ranges = vec![RangeRef::new(dest, dest)];

crates/engine/src/cmd/forecast.rs

@@ -36,6 +36,20 @@ fn max_periods(history: usize) -> u32 {
     u32::try_from(MAX_WORK / h).unwrap_or(u32::MAX).clamp(1, MAX_PERIODS)
 }
 
+/// Most forecast rows when the model is fit to the first `fit` of `history` rows. With a Forecast
+/// Start inside the history, every row after it is forecast too (a hindcast row holds the same
+/// ETS formulas, each refitting the model over the `fit` rows), so those rows count against
+/// [`MAX_WORK`] before any forecast row does. `None` when the hindcast alone exceeds it.
+fn max_periods_from(history: usize, fit: usize) -> Option<u32> {
+    if fit >= history {
+        return Some(max_periods(history));
+    }
+    let f = u64::try_from(fit).unwrap_or(u64::MAX).max(1);
+    let hindcast = u64::try_from(history - fit).unwrap_or(u64::MAX);
+    let rest = (MAX_WORK / f).checked_sub(hindcast).filter(|r| *r >= 1)?;
+    Some(u32::try_from(rest).unwrap_or(u32::MAX).min(MAX_PERIODS))
+}
+
 pub fn specs() -> Vec<CommandSpec> {
     vec![cmd!(
         "data.forecastSheet",
@@ -257,13 +271,15 @@ fn forecast_sheet(s: &mut Session, p: &Json) -> Result<Json> {
             }
         }
     };
-    let cap = max_periods(rows.len());
+    let cap = max_periods_from(rows.len(), fit).ok_or_else(|| {
+        EngineError::Other("The forecast start is too early for this much history: choose a later forecast start or less history.".into())
+    })?;
     let periods = match end {
         Some(end) => steps_to(&timeline, end, cap)?,
         None => match number(p, "periods")? {
             Some(n) if n >= 1.0 && n.ceil() <= f64::from(cap) => n.ceil() as u32,
             Some(_) => return Err(bad(CMD, format!("`periods` is from 1 to {cap} for {} rows of history", rows.len()))),
-            None => default_periods(rows.len()),
+            None => default_periods(rows.len()).min(cap),
         },
     };
     let future: Vec<f64> =
@@ -530,6 +546,32 @@ mod tests {
         assert_eq!(s.doc().unwrap().wb.sheets.len(), sheets - 1);
     }
 
+    #[test]
+    fn hindcast_rows_count_against_the_work_limit() {
+        use super::{MAX_WORK, max_periods, max_periods_from};
+        assert_eq!(max_periods_from(1_300, 1_300), Some(max_periods(1_300)));
+        // 2,000 rows fit to the first 1,899: 101 hindcast rows, then 162 forecast rows.
+        assert_eq!(max_periods_from(2_000, 1_899), Some(162));
+        // Fit to the first 1,000: the 1,000 hindcast rows alone are twice the limit.
+        assert_eq!(max_periods_from(2_000, 1_000), None);
+        for (h, f) in [(2_000usize, 1_899usize), (10_000, 9_990), (100, 2), (60, 50)] {
+            if let Some(p) = max_periods_from(h, f) {
+                assert!((u64::from(p) + (h - f) as u64) * f as u64 <= MAX_WORK, "{h} {f}");
+            }
+        }
+        let mut s = Session::new();
+        s.new_workbook();
+        let mut rows = vec![json!(["t", "y"])];
+        rows.extend((1..=2_000).map(|t| json!([t, (t % 7) as f64 + t as f64 * 0.5])));
+        s.execute("range.setValues", json!({"range": "A1", "values": rows})).unwrap();
+        let sheets = s.doc().unwrap().wb.sheets.len();
+        let err = s.execute("data.forecastSheet", json!({"range": "A1:B2001", "forecastStart": 1_001})).expect_err("hindcast too long");
+        assert!(err.to_string().contains("forecast start is too early"), "{err}");
+        let err = s.execute("data.forecastSheet", json!({"range": "A1:B2001", "forecastStart": 1_900, "periods": 163})).expect_err("past the cap");
+        assert!(err.to_string().contains("from 1 to 162"), "{err}");
+        assert_eq!(s.doc().unwrap().wb.sheets.len(), sheets);
+    }
+
     #[test]
     fn history_and_periods_are_capped() {
         use super::{MAX_HISTORY, MAX_PERIODS, MAX_WORK, default_periods, max_periods};

crates/engine/src/cmd/insert.rs

@@ -1733,13 +1733,7 @@ fn clear_cf(s: &mut Session, p: &Json) -> Result<Json> {
             sh.cond_formats.clear();
         } else {
             for cf in sh.cond_formats.iter_mut() {
-                let before = RangeRef::top_left(&cf.ranges);
                 cf.ranges.retain(|r| !ranges.iter().any(|x| x.intersects(r)));
-                // The relative formulas are written for the top-left cell: when it goes, they're
-                // rewritten for the new one, so the areas left keep reading the same cells.
-                if let (Some(from), Some(to)) = (before, RangeRef::top_left(&cf.ranges)) {
-                    rebase_cf_formulas(&mut cf.rule, from, to);
-                }
             }
             sh.cond_formats.retain(|c| !c.ranges.is_empty());
         }
@@ -1747,19 +1741,6 @@ fn clear_cf(s: &mut Session, p: &Json) -> Result<Json> {
     })
 }
 
-/// Moves the relative references of a rule's per-cell formulas written for `from` to `to`.
-fn rebase_cf_formulas(rule: &mut CfRule, from: CellRef, to: CellRef) {
-    let mv = |f: &str| crate::cmd::data::move_rule_formula(f, from, to);
-    match rule {
-        CfRule::CellIs { a, b, .. } => {
-            *a = mv(a);
-            *b = b.as_deref().map(mv);
-        }
-        CfRule::Expression { formula, .. } => *formula = mv(formula),
-        _ => {}
-    }
-}
-
 fn manage_cf(s: &mut Session, p: &Json) -> Result<Json> {
     let sheet = target_sheet(s, p)?;
     if p.get("delete").is_none() && p.get("moveUp").is_none() && p.get("moveDown").is_none() {

crates/engine/src/io.rs

@@ -3,7 +3,7 @@
 use std::fmt::Write as _;
 
 use gridcraft_core::{CellRef, RangeRef};
-use gridcraft_model::{LineIndex, Sheet, Workbook};
+use gridcraft_model::{Sheet, Workbook};
 
 use crate::{EngineError, Result};
 
@@ -548,23 +548,6 @@ fn table_dir(sh: &Sheet) -> &'static str {
 const CLIPBOARD_HTML_MAX_BYTES: usize = 4 * 1024 * 1024;
 const CLIPBOARD_HTML_MAX_CELLS: u64 = 10_000;
 
-/// The merge covering each cell of `rect`, as `Sheet::merge_at` would find it (the first in the
-/// sheet's list), built once so a table lookup is one probe instead of a scan of every merge.
-/// `None` when overlapping merges would cost more than a few visits per cell of `rect`: a
-/// hostile file's merge list can't multiply the work of a bounded export.
-fn merge_index(sh: &Sheet, rect: RangeRef) -> Option<std::collections::HashMap<CellRef, RangeRef>> {
-    let mut map = std::collections::HashMap::new();
-    let mut left = rect.count().saturating_mul(4);
-    for m in &sh.merges {
-        let Some(part) = m.intersection(&rect) else { continue };
-        left = left.checked_sub(part.count())?;
-        for c in part.iter() {
-            map.entry(c).or_insert(*m);
-        }
-    }
-    Some(map)
-}
-
 /// An HTML fragment for the same range as `plain_text`, previously produced by
 /// `display::range_text`. Large copies keep plain text only; never return a partial table.
 pub(crate) fn range_html(wb: &Workbook, sheet: usize, r: RangeRef, plain_text: &str) -> Option<String> {
@@ -573,7 +556,6 @@ pub(crate) fn range_html(wb: &Workbook, sheet: usize, r: RangeRef, plain_text: &
         return None;
     }
     let sh = wb.sheet(sheet)?;
-    let merges = merge_index(sh, r)?;
     let mut out = ClipboardHtml(String::new());
     write!(out, "<table{} style=\"border-collapse:collapse;font-family:Calibri,Carlito,Arial,sans-serif;font-size:11pt\">", table_dir(sh)).ok()?;
     for row in r.start.row..=r.end.row {
@@ -583,7 +565,7 @@ pub(crate) fn range_html(wb: &Workbook, sheet: usize, r: RangeRef, plain_text: &
         out.write_str("<tr>").ok()?;
         for col in r.start.col..=r.end.col {
             let c = CellRef::new(row, col);
-            let span = if let Some(merged) = merges.get(&c).and_then(|m| m.intersection(&r)) {
+            let span = if let Some(merged) = sh.merges.iter().find(|m| m.contains(c)).and_then(|m| m.intersection(&r)) {
                 let first_row = (merged.start.row..=merged.end.row).find(|&row| !sh.is_row_hidden(row))?;
                 if c != CellRef::new(first_row, merged.start.col) {
                     continue;
@@ -646,14 +628,6 @@ const HTML_EXPORT_MAX_ROWS: u32 = 100_001;
 /// tall, wide one) would otherwise be gigabytes of `<td></td>` before finishing (#2387).
 const HTML_EXPORT_MAX_CELLS: u64 = 4_000_000;
 
-/// Most bytes of one web page. Every cell may hold long text (shared across many cells in the
-/// file), so the cell count alone doesn't bound the page; past this the export fails instead.
-const HTML_EXPORT_MAX_BYTES: usize = 256 * 1024 * 1024;
-
-fn html_too_big() -> EngineError {
-    EngineError::Other(format!("the web page would be over {} MiB. Save as .xlsx or CSV instead.", HTML_EXPORT_MAX_BYTES / (1024 * 1024)))
-}
-
 /// A sheet as a standalone HTML table (Save as Web Page). A sheet with pictures gets the sheet's
 /// own column widths and row heights so each picture and chart (inline SVG) can sit at its anchor.
 pub fn to_html(wb: &Workbook, sheet: usize) -> Result<String> {
@@ -696,23 +670,6 @@ pub fn to_html(wb: &Workbook, sheet: usize) -> Result<String> {
                 r.width()
             )));
         }
-        let merges = merge_index(sh, r).ok_or_else(|| EngineError::Other("the sheet's merged cells overlap too much for a web page.".into()))?;
-        // Visible rows and columns of the table before each line, so a merge's span is counted
-        // in constant time whatever the file says its size is.
-        let visible_before = |hidden: &dyn Fn(u32) -> bool, from: u32, to: u32| {
-            let mut v = Vec::with_capacity((to - from) as usize + 2);
-            v.push(0u32);
-            for line in from..=to {
-                v.push(v.last().copied().unwrap_or(0) + u32::from(!hidden(line)));
-            }
-            v
-        };
-        let rows_before = visible_before(&|y| sh.is_row_hidden(y), r.start.row, r.end.row);
-        let cols_before = visible_before(&|x| sh.is_col_hidden(x), r.start.col, r.end.col);
-        let visible = |before: &[u32], from: u32, a: u32, b: u32| {
-            let at = |line: u32| before.get((line - from) as usize).copied().unwrap_or(0);
-            at(b + 1) - at(a)
-        };
         if fixed {
             out.push_str("<colgroup>");
             for col in (r.start.col..=r.end.col).filter(|&c| !sh.is_col_hidden(c)) {
@@ -731,19 +688,20 @@ pub fn to_html(wb: &Workbook, sheet: usize) -> Result<String> {
             }
             for col in r.start.col..=r.end.col {
                 let c = CellRef::new(row, col);
-                let merge = merges.get(&c);
-                if merge.is_some_and(|m| m.start != c) || (fixed && sh.is_col_hidden(col)) {
+                if sh.merges.iter().any(|m| m.contains(c) && m.start != c) || (fixed && sh.is_col_hidden(col)) {
                     continue;
                 }
                 let text = crate::display::cell_text(wb, sh, c);
                 let dir = CellDir::of(sh, c, &text);
                 let css = html_cell_css(wb, sh, c, dir);
-                let span = merge
+                let span = sh
+                    .merges
+                    .iter()
+                    .find(|m| m.start == c)
                     .map(|m| {
                         if fixed {
-                            // Spans count the table's visible lines: the merge is clipped to the table.
-                            let rows = visible(&rows_before, r.start.row, m.start.row, m.end.row.min(r.end.row));
-                            let cols = visible(&cols_before, r.start.col, m.start.col, m.end.col.min(r.end.col));
+                            let rows = (m.start.row..=m.end.row).filter(|&y| !sh.is_row_hidden(y)).count();
+                            let cols = (m.start.col..=m.end.col).filter(|&x| !sh.is_col_hidden(x)).count();
                             format!(" rowspan=\"{rows}\" colspan=\"{cols}\"")
                         } else {
                             format!(" rowspan=\"{}\" colspan=\"{}\"", m.height(), m.width())
@@ -751,9 +709,6 @@ pub fn to_html(wb: &Workbook, sheet: usize) -> Result<String> {
                     })
                     .unwrap_or_default();
                 let _ = write!(out, "<td style=\"{css}\"{}{span}>{}</td>", dir.attr(), esc(&text));
-                if out.len() > HTML_EXPORT_MAX_BYTES {
-                    return Err(html_too_big());
-                }
             }
             out.push_str("</tr>");
         }
@@ -761,15 +716,12 @@ pub fn to_html(wb: &Workbook, sheet: usize) -> Result<String> {
     out.push_str("</table>");
     if fixed {
         // Sheet units are CSS pixels; the table starts at the used range, not at A1.
-        // Indexed positions: each anchor would otherwise sum every custom row and column before it.
-        let ri = LineIndex::new(&sh.rows, sh.default_row_height, gridcraft_core::MAX_ROWS);
-        let ci = LineIndex::new(&sh.cols, sh.default_col_width, gridcraft_core::MAX_COLS);
-        let (left, top) = used.map_or((0.0, 0.0), |r| (ci.start(r.start.col), ri.start(r.start.row)));
+        let (left, top) = used.map_or((0.0, 0.0), |r| (sh.col_left(r.start.col), sh.row_top(r.start.row)));
         let place = |a: &gridcraft_model::Anchor| {
             format!(
                 "position:absolute;left:{}px;top:{}px;width:{}px;height:{}px",
-                ci.start(a.cell.col) - left + f64::from(a.dx),
-                ri.start(a.cell.row) - top + f64::from(a.dy),
+                sh.col_left(a.cell.col) - left + f64::from(a.dx),
+                sh.row_top(a.cell.row) - top + f64::from(a.dy),
                 a.width.max(0.0),
                 a.height.max(0.0)
             )
@@ -783,9 +735,6 @@ pub fn to_html(wb: &Workbook, sheet: usize) -> Result<String> {
                 esc(&im.alt),
                 place(&im.anchor)
             );
-            if out.len() > HTML_EXPORT_MAX_BYTES {
-                return Err(html_too_big());
-            }
         }
         for ch in &sh.charts {
             if let Some(svg) = crate::chart_svg::chart_svg(wb, sheet, ch, &place(&ch.anchor)) {

crates/engine/src/io/tests.rs

@@ -604,57 +604,3 @@ fn opening_google_sheets_export_unwraps_only_formulas_gridcraft_calculates() {
     assert_eq!(text("A2").as_deref(), Some("IFERROR(__XLUDF.DUMMYFUNCTION(\"GOOGLETRANSLATE(\"\"hi\"\",\"\"en\"\",\"\"fr\"\")\"),\"salut\")"));
     assert_eq!(opened.sheets[0].cells.get(CellRef::parse("A2").unwrap()).map(|c| c.value.clone()), Some(Value::text("salut")));
 }
-
-/// Merges far from what is copied or exported, in a hostile number, are indexed once instead of
-/// being scanned for every cell; a merge running past the table is clipped to it.
-#[test]
-fn html_merge_lookups_and_spans_stay_bounded() {
-    let mut wb = book_with_picture("A1", (0, 0));
-    let sh = wb.sheet_mut(0).unwrap();
-    for i in 0..200_000u32 {
-        sh.merges.push(RangeRef::new(CellRef::new(500_000 + i * 2, 5), CellRef::new(500_000 + i * 2, 6)));
-    }
-    sh.merges.push(RangeRef::new(CellRef::new(0, 0), CellRef::new(gridcraft_core::MAX_ROWS - 1, 1)));
-    sh.set_value(CellRef::new(2, 1), gridcraft_core::Value::Number(2.0));
-    let html = copied(&wb, "A1:C50");
-    assert!(html.contains("rowspan=\"50\" colspan=\"2\""), "{html}");
-    let page = to_html(&wb, 0).unwrap();
-    // The table is A1:B3 (the used range): the whole-height merge spans its three rows only.
-    assert!(page.contains("rowspan=\"3\" colspan=\"2\""), "{page}");
-    // Merges stacked over one another past a few per cell are refused, not walked.
-    let sh = wb.sheet_mut(0).unwrap();
-    sh.merges = vec![RangeRef::new(CellRef::new(0, 0), CellRef::new(2, 1)); 100];
-    assert!(to_html(&wb, 0).is_err());
-    assert!(range_html(&wb, 0, RangeRef::parse("A1:B3").unwrap(), "").is_none());
-}
-
-/// Thousands of pictures over thousands of custom rows: each is placed through a row index.
-#[test]
-fn html_export_places_many_pictures_over_many_custom_rows() {
-    let mut wb = book_with_picture("A1", (0, 0));
-    let sh = wb.sheet_mut(0).unwrap();
-    for row in 0..50_000 {
-        sh.rows.insert(row, gridcraft_model::LineInfo { size: Some(30.0), ..Default::default() });
-    }
-    let image = sh.images[0].clone();
-    for i in 0..5_000u32 {
-        let mut im = image.clone();
-        im.anchor.cell = CellRef::new(40_000 + i, 0);
-        sh.images.push(im);
-    }
-    let page = to_html(&wb, 0).unwrap();
-    assert!(page.contains(&format!("top:{}px", 30 * 44_999)), "last picture placed by the index");
-}
-
-/// One long text shown by many cells: the page fails at its byte limit instead of growing on.
-#[test]
-fn html_export_refuses_a_page_past_its_byte_limit() {
-    let mut wb = Workbook::new();
-    let sh = wb.sheet_mut(0).unwrap();
-    let text = gridcraft_core::Value::text("x".repeat(32_000));
-    for row in 0..10_000 {
-        sh.set_value(CellRef::new(row, 0), text.clone());
-    }
-    let err = to_html(&wb, 0).unwrap_err();
-    assert!(err.to_string().contains("MiB"), "{err}");
-}

crates/engine/src/tests.rs

@@ -2743,78 +2743,6 @@ fn validation_formulas_are_relative_and_see_the_new_value() {
     assert!(!ok(&mut s, "C1", "50"));
 }
 
-#[test]
-fn multi_area_rule_formulas_are_relative_to_the_top_left_cell_of_all_areas() {
-    // Issue #3152: Excel writes the formula for the top-left cell of all the areas (H26), whatever
-    // order they are listed in, not for the first area listed (H62).
-    let mut s = s();
-    s.execute("range.setValues", json!({"range": "F26:F27", "values": [[4], [5]]})).unwrap();
-    s.execute("data.validation", json!({"range": "H62:H68,H26:H27,H93:H95", "type": "custom", "formula1": "=MOD($H26,$F26)=0"})).unwrap();
-    let ok = |s: &mut Session, cell: &str, input: &str| s.execute("data.validate", json!({"cell": cell, "input": input})).unwrap()["ok"] == true;
-    assert!(ok(&mut s, "H26", "4"));
-    assert!(ok(&mut s, "H26", "8"));
-    assert!(!ok(&mut s, "H26", "3"));
-    assert!(ok(&mut s, "H27", "10"));
-    assert!(!ok(&mut s, "H27", "4"));
-
-    // Conditional formats anchor on the same cell: `=D2>0` on D5:D6,D2:D3 checks D2 at D2.
-    s.execute("range.setValues", json!({"range": "D2:D6", "values": [[1], [0], [0], [1], [0]]})).unwrap();
-    s.execute("home.conditionalFormat", json!({"range": "D5:D6,D2:D3", "rule": {"type": "expression", "formula": "=D2>0", "preset": "greenFill"}}))
-        .unwrap();
-    let wb = s.doc().unwrap().wb.clone();
-    let mut cache = crate::cf::CfCache::new();
-    let mut styled = |c: &str| cache.look(&wb, 0, CellRef::parse(c).unwrap()).and_then(|l| l.style).is_some();
-    assert_eq!([styled("D2"), styled("D3"), styled("D5"), styled("D6")], [true, false, true, false]);
-}
-
-#[test]
-fn removing_a_rules_top_left_cell_rewrites_its_formulas_for_the_new_one() {
-    let mut s = s();
-    let ok = |s: &mut Session, cell: &str, input: &str| s.execute("data.validate", json!({"cell": cell, "input": input})).unwrap()["ok"] == true;
-    let f1 = |s: &Session| s.doc().unwrap().wb.active().unwrap().validations[0].f1.clone();
-
-    // One area: clearing A1 off A1:A9 leaves A2:A9, whose cells still check themselves.
-    s.execute("data.validation", json!({"range": "A1:A9", "type": "custom", "formula1": "=A1>10"})).unwrap();
-    s.execute("data.validation", json!({"range": "A1", "clear": true})).unwrap();
-    assert_eq!(f1(&s), "A2>10");
-    assert!(ok(&mut s, "A2", "20"));
-    assert!(!ok(&mut s, "A2", "5"));
-    s.execute("data.validation", json!({"range": "A1:A9", "clear": true})).unwrap();
-
-    // Several areas: clearing H26 moves the top-left cell to H27, where `$H27,$F27` is checked.
-    s.execute("range.setValues", json!({"range": "F26:F27", "values": [[4], [5]]})).unwrap();
-    s.execute("data.validation", json!({"range": "H62:H68,H26:H27", "type": "custom", "formula1": "=MOD($H26,$F26)=0"})).unwrap();
-    s.execute("data.validation", json!({"range": "H26", "clear": true})).unwrap();
-    assert_eq!(f1(&s), "MOD($H27,$F27)=0");
-    assert!(ok(&mut s, "H27", "10"));
-    assert!(!ok(&mut s, "H27", "4"));
-    // Absolute and literal formulas don't move.
-    s.execute("data.validation", json!({"range": "J1:J3", "type": "list", "formula1": "=$B$1:$B$2"})).unwrap();
-    s.execute("data.validation", json!({"range": "J1", "clear": true})).unwrap();
-    let dv = s.doc().unwrap().wb.active().unwrap().validations.iter().find(|d| d.ranges[0].a1() == "J2:J3").unwrap().f1.clone();
-    assert_eq!(dv, "$B$1:$B$2");
-
-    // Conditional formats: Clear Rules on D2 drops the D2:D3 area, and D5:D6 keeps reading itself.
-    s.execute("range.setValues", json!({"range": "D2:D6", "values": [[1], [0], [0], [0], [1]]})).unwrap();
-    s.execute("home.conditionalFormat", json!({"range": "D5:D6,D2:D3", "rule": {"type": "expression", "formula": "=D2>0", "preset": "greenFill"}}))
-        .unwrap();
-    s.execute("range.setValues", json!({"range": "E2:E6", "values": [[1], [0], [0], [0], [1]]})).unwrap();
-    s.execute("range.setValues", json!({"range": "G2:G6", "values": [[0], [9], [9], [9], [0]]})).unwrap();
-    s.execute(
-        "home.conditionalFormat",
-        json!({"range": "E5:E6,E2:E3", "rule": {"type": "cellIs", "operator": "greater", "value": "=G2", "preset": "lightRedFill"}}),
-    )
-    .unwrap();
-    s.execute("home.clearRules", json!({"range": "D2,E2"})).unwrap();
-    let rules: Vec<gridcraft_model::CfRule> = s.doc().unwrap().wb.active().unwrap().cond_formats.iter().map(|c| c.rule.clone()).collect();
-    assert!(rules.iter().any(|r| matches!(r, gridcraft_model::CfRule::Expression { formula, .. } if formula == "D5>0")), "{rules:?}");
-    assert!(rules.iter().any(|r| matches!(r, gridcraft_model::CfRule::CellIs { a, .. } if a == "G5")), "{rules:?}");
-    let wb = s.doc().unwrap().wb.clone();
-    let mut cache = crate::cf::CfCache::new();
-    let mut styled = |c: &str| cache.look(&wb, 0, CellRef::parse(c).unwrap()).and_then(|l| l.style).is_some();
-    assert_eq!([styled("D5"), styled("D6"), styled("E5"), styled("E6")], [false, true, false, true]);
-}
-
 #[test]
 fn samples_build() {
     for (name, _) in crate::sample::SAMPLES {

crates/ui-egui/src/grid/editor.rs

@@ -125,7 +125,7 @@ pub(super) fn list_picker(app: &mut SheetApp, ui: &mut egui::Ui, geo: &Geo, was_
         app.grid.list_picker = None;
         return;
     };
-    let items = gridcraft_engine::cmd::data::list_items(&wb, si, c, &dv);
+    let items = gridcraft_engine::cmd::data::list_items(&wb, si, &dv);
     let r = geo.cell_rect(sh, c);
     // Fit the popup to its rows (up to LIST_PICKER_MAX_ROWS); without a minimum the scroll area collapses to its 64 px default.
     let height = list_picker_height(items.len(), LIST_PICKER_ROW_H, ui.spacing().item_spacing.y);

crates/ui-egui/src/ribbon/home.rs

@@ -622,13 +622,10 @@ fn size_combo(app: &mut SheetApp, ui: &mut Ui, st: &Style) {
     let arrow_rect = Rect::from_min_max(egui::pos2(frame.right() - 16.0, frame.top() + 1.0), egui::pos2(frame.right() - 1.0, frame.bottom() - 1.0));
     let mut field_ui =
         ui.new_child(egui::UiBuilder::new().max_rect(text_rect.shrink2(vec2(6.0, 0.0))).layout(egui::Layout::left_to_right(egui::Align::Center)));
-    // The text edit is `interact_size.y` tall and puts its text at the top of that unless told
-    // otherwise: center it, on the Font name's baseline (#3155).
     let out = egui::TextEdit::singleline(&mut text)
         .id(field)
         .font(theme::ui_font(12.5))
         .frame(egui::Frame::NONE)
-        .align(egui::Align2::LEFT_CENTER)
         .desired_width(text_rect.width() - 12.0)
         .show(&mut field_ui);
     let resp = out.response;

crates/ui-egui/tests/it/font_size_box.rs

@@ -1,7 +1,6 @@
-//! Home ▸ Font Size is a box you type a size into, with the standard sizes behind its arrow (#932),
-//! and the size sits in the middle of that box (#3155).
+//! Home ▸ Font Size is a box you type a size into, with the standard sizes behind its arrow (#932).
 
-use egui::{Event, Key, Modifiers, Rect, Shape, accesskit::Role};
+use egui::{Event, Key, Modifiers, accesskit::Role};
 use egui_kittest::kittest::Queryable as _;
 use gridcraft_engine::Session;
 use gridcraft_engine::core::{CellRef, Value};
@@ -125,31 +124,3 @@ fn the_arrow_opens_the_plain_list_of_sizes() {
     h.run_steps(3);
     assert_eq!(size(&h, "A1"), 12.0, "Down from 11 then Enter picks 12");
 }
-
-/// The on-screen box of the painted text `text` that overlaps `within`. The grid's row headers
-/// paint "11" too, so the size has to be looked for inside its own box.
-fn painted_text(h: &Harness, text: &str, within: Rect) -> Rect {
-    h.output()
-        .shapes
-        .iter()
-        .find_map(|s| match &s.shape {
-            Shape::Text(t) if t.galley.job.text == text => {
-                let rect = t.galley.rect.translate(t.pos.to_vec2());
-                within.intersects(rect).then_some(rect)
-            }
-            _ => None,
-        })
-        .unwrap_or_else(|| panic!("{text:?} is painted inside {within:?}"))
-}
-
-#[test]
-/// A text edit aligns its text to the top of its rect unless told otherwise, which left the size
-/// 4 pt above the Font name's baseline.
-fn the_size_is_vertically_centered_in_its_box() {
-    let h = harness();
-    let field = h.get_by_role_and_label(Role::TextInput, "Font Size").rect();
-    let value = painted_text(&h, "11", field);
-    let name = painted_text(&h, "Calibri", Rect::EVERYTHING);
-    assert!((value.center().y - field.center().y).abs() <= 1.0, "the size is centered in its box: {value:?} in {field:?}");
-    assert!((value.center().y - name.center().y).abs() <= 1.0, "the size is on the Font name's baseline: {value:?} against {name:?}");
-}

crates/ui-egui/tests/it/ribbon_layout.rs

@@ -104,10 +104,7 @@ struct Clicks {
 #[test]
 /// The main button clicks once and the arrow twice separately; the tooltip keeps the platform shortcut, and the icon sits above the full-width label.
 fn big_split_button_separates_the_default_action_from_the_menu() {
-    // The ribbon picks the shortcut by the OS egui reports, which kittest pins to Nix unless told:
-    // pin macOS, so the check is the same on every host (the other platforms' text is in
-    // `widgets::tests`).
-    let mut h = crate::common::builder().with_size(vec2(300.0, 200.0)).with_os(egui::os::OperatingSystem::Mac).build_ui_state(
+    let mut h = crate::common::builder().with_size(vec2(300.0, 200.0)).build_ui_state(
         |ui, c: &mut Clicks| {
             let (main, arrow) = widgets::big_split_button(ui, Icon::Sum, "Auto\nSum", "AutoSum");
             c.main += u32::from(main.clicked());
@@ -128,7 +125,8 @@ fn big_split_button_separates_the_default_action_from_the_menu() {
     h.ctx.all_styles_mut(|s| s.interaction.tooltip_delay = 0.0);
     h.get_by_label("Auto Sum").hover();
     h.run_steps(6);
-    assert!(h.query_by_value("AutoSum (\u{2318}\u{21e7}T)").is_some(), "tooltip with the macOS shortcut");
+    let shortcut = if cfg!(target_os = "macos") { "AutoSum (\u{2318}\u{21e7}T)" } else { "AutoSum (Alt+=)" };
+    assert!(h.query_by_value(shortcut).is_some(), "tooltip with the shortcut");
     // The icon part sits above the label part, across the full width.
     let main = h.get_by_label("Auto Sum").rect();
     let arrow = h.get_by_label("Auto Sum options").rect();

crates/xlsx/src/sheet_write/rules.rs

@@ -52,10 +52,8 @@ pub(super) fn x14_cfvo(v: &CfValueKind) -> String {
     format!("<x14:cfvo type=\"{ty}\"><xm:f>{}</xm:f></x14:cfvo>", esc(&val))
 }
 
-/// One `cfRule` element. The formulas generated for text, blank, error and date rules refer to the
-/// top-left cell of all the rule's areas, the cell Excel reads relative references from.
 pub(super) fn cf_rule_xml(cf: &CondFormat, priority: u32, out: &mut Out) -> String {
-    let tl = RangeRef::top_left(&cf.ranges).map(|c| c.a1()).unwrap_or_else(|| "A1".into());
+    let tl = cf.ranges.first().map(|r| r.start.a1()).unwrap_or_else(|| "A1".into());
     let stop = if cf.stop_if_true { " stopIfTrue=\"1\"" } else { "" };
     let mut dxf = |st: &Style| dxf_id(&mut out.dxfs, st);
     let f = |x: &str| format!("<formula>{}</formula>", esc(&text_to_file(x)));

crates/xlsx/src/tests/roundtrip.rs

@@ -1678,21 +1678,3 @@ fn workbook_view_writer_clamps_out_of_range_model_values() {
         assert_eq!(back.view.tab_ratio, 1000);
     }
 }
-
-#[test]
-fn generated_rule_formulas_use_the_top_left_cell_of_every_area() {
-    // Issue #3152: the areas aren't in top-to-bottom order; the formula is written for C2, not C5.
-    let mut wb = Workbook::new();
-    let red = Box::new(Style::default());
-    wb.sheet_mut(0).unwrap().cond_formats.push(CondFormat {
-        ranges: vec![rr("C5:C6"), rr("C2:C3")],
-        rule: CfRule::ContainsText { text: "x".into(), style: red },
-        priority: 1,
-        stop_if_true: false,
-    });
-    let bytes = write_xlsx(&wb).unwrap();
-    let mut z = zip::ZipArchive::new(std::io::Cursor::new(bytes)).unwrap();
-    let mut xml = String::new();
-    z.by_name("xl/worksheets/sheet1.xml").unwrap().read_to_string(&mut xml).unwrap();
-    assert!(xml.contains("<formula>NOT(ISERROR(SEARCH(\"x\",C2)))</formula>"), "{xml}");
-}