FORMULATEXT and the cell editor keep a hidden formula's source hidden

crates/calc/src/eval/call.rs

@@ -52,13 +52,16 @@ impl<'h> Evaluator<'h> {
             "ISFORMULA" | "FORMULATEXT" => {
                 let Some(Ev::R(a)) = args.first().map(|a| self.eval(a)) else { return err(CellError::NA) };
                 let Some(a) = a.first() else { return err(CellError::NA) };
-                let f = self.host.workbook().sheet(a.sheet).and_then(|s| s.cell(a.range.start)).and_then(|c| c.formula.clone());
+                let wb = self.host.workbook();
+                let f = wb.sheet(a.sheet).and_then(|s| s.cell(a.range.start)).and_then(|c| c.formula.clone());
+                // A formula formatted Hidden on a protected sheet stays hidden from FORMULATEXT too.
+                let hidden = wb.sheet(a.sheet).is_some_and(|s| s.is_protected() && wb.styles.get(s.style_id(a.range.start)).protection.hidden);
                 if name == "ISFORMULA" {
                     Ev::V(Value::Bool(f.is_some()))
                 } else {
                     match f {
-                        Some(f) => Ev::V(Value::text(format!("={}", f.text))),
-                        None => err(CellError::NA),
+                        Some(f) if !hidden => Ev::V(Value::text(format!("={}", f.text))),
+                        _ => err(CellError::NA),
                     }
                 }
             }

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

@@ -695,79 +695,6 @@ fn bands_unit() {
     assert!(w.len() > 2);
 }
 
-/// The wrapper `wrap_lines` replaced, re-measuring strings, as the reference for its lines.
-fn wrap_lines_remeasuring(text: &str, font: Font, size: f32, width: f32) -> Vec<String> {
-    let mut out = Vec::new();
-    for para in text.split('\n') {
-        let mut line = String::new();
-        for word in para.split(' ') {
-            let cand = if line.is_empty() { word.to_string() } else { format!("{line} {word}") };
-            if line.is_empty() || gridcraft_pdf::text_width(font, size, &cand) <= width {
-                line = cand;
-            } else {
-                out.push(std::mem::take(&mut line));
-                line = word.to_string();
-            }
-            while gridcraft_pdf::text_width(font, size, &line) > width && line.chars().count() > 1 {
-                let chars: Vec<char> = line.chars().collect();
-                let (mut lo, mut hi) = (1usize, chars.len());
-                while lo < hi {
-                    let mid = lo + (hi - lo).div_ceil(2);
-                    let cut: String = chars[..mid].iter().collect();
-                    if gridcraft_pdf::text_width(font, size, &cut) <= width {
-                        lo = mid;
-                    } else {
-                        hi = mid - 1;
-                    }
-                }
-                if lo == chars.len() {
-                    break;
-                }
-                out.push(chars[..lo].iter().collect());
-                line = chars[lo..].iter().collect();
-            }
-            if out.len() > 2000 {
-                return out;
-            }
-        }
-        out.push(line);
-    }
-    out
-}
-
-#[test]
-fn wrap_lines_matches_the_remeasuring_wrapper() {
-    let texts = [
-        "the quick brown fox jumps",
-        "Supercalifragilistic",
-        "a  b   c\n\nverylongwordthatneedsbreaking short\nend ",
-        "Wide WWWWWWWWWW words, iiiiiiii narrow ones; mixed MMMMiiiiMMMM",
-        "€ ü ß — unicode Ünïcödé text",
-        "",
-        " ",
-    ];
-    for text in texts {
-        for font in [Font::Helvetica, Font::HelveticaBold, Font::Courier] {
-            for (size, width) in [(10.0, 50.0), (10.0, 20.0), (11.0, 1.0), (8.0, 300.0), (12.0, 0.0)] {
-                assert_eq!(wrap_lines(text, font, size, width), wrap_lines_remeasuring(text, font, size, width), "{text:?} {font:?} {size} {width}");
-            }
-        }
-    }
-}
-
-#[test]
-fn wrapping_a_long_word_in_a_narrow_box_stops_at_the_line_limit() {
-    // One character per line: the old wrapper re-measured and copied the rest of the word for
-    // each of the 100,000 lines before checking the limit.
-    let word = "w".repeat(100_000);
-    let lines = wrap_lines(&word, Font::Helvetica, 10.0, 1.0);
-    assert!(lines.len() <= 2002, "{}", lines.len());
-    assert!(lines.iter().all(|l| l == "w"));
-    // A long paragraph in a very wide box is one line.
-    let para = vec!["word"; 50_000].join(" ");
-    assert_eq!(wrap_lines(&para, Font::Helvetica, 10.0, 1.0e9), vec![para.clone()]);
-}
-
 #[test]
 fn center_across_spans_following_empty_center_across_cells() {
     let mut styles = StyleTable::default();

crates/engine/src/cmd/print/text.rs

@@ -3,57 +3,42 @@ use super::{CellRef, Color, Font, HAlign, MAX_COLS, Page, Point, RangeRef, Sheet
 
 const PAD_PX: f32 = 2.0;
 
-/// Most lines [`wrap_lines`] returns (it may return one more, the rest of a paragraph).
-const MAX_WRAP_LINES: usize = 2000;
-
 /// Word-wraps `text` to `width` points.
-///
-/// Widths are kept as running sums of glyph widths (the sum `text_width` makes), so each
-/// character is measured once: re-measuring the line for every word, or the rest of an
-/// over-long word for every piece cut from it, made a long paragraph or word quadratic.
 pub(super) fn wrap_lines(text: &str, font: Font, size: f32, width: f32) -> Vec<String> {
-    let units_of = |s: &str| -> u64 { s.chars().map(|c| u64::from(font.char_width(c))).sum() };
-    let fits = |units: u64| units as f32 * size / 1000.0 <= width;
-    let space = units_of(" ");
     let mut out = Vec::new();
     for para in text.split('\n') {
         let mut line = String::new();
-        let mut line_units: u64 = 0;
         for word in para.split(' ') {
-            let word_units = units_of(word);
-            if line.is_empty() {
-                line.push_str(word);
-                line_units = word_units;
-            } else if fits(line_units + space + word_units) {
-                line.push(' ');
-                line.push_str(word);
-                line_units += space + word_units;
+            let cand = if line.is_empty() { word.to_string() } else { format!("{line} {word}") };
+            if line.is_empty() || gridcraft_pdf::text_width(font, size, &cand) <= width {
+                line = cand;
             } else {
                 out.push(std::mem::take(&mut line));
-                line.push_str(word);
-                line_units = word_units;
+                line = word.to_string();
             }
-            // Break a single over-long word by characters: each piece is the longest that fits
-            // (at least one character).
-            if !fits(line_units) && line.chars().nth(1).is_some() {
-                let mut piece = String::new();
-                let mut units: u64 = 0;
-                for c in line.chars() {
-                    let w = u64::from(font.char_width(c));
-                    if !piece.is_empty() && !fits(units + w) {
-                        out.push(std::mem::take(&mut piece));
-                        units = 0;
-                        if out.len() > MAX_WRAP_LINES {
-                            return out;
-                        }
+            // Break a single over-long word by characters. The cut that fits is found by binary
+            // search (each try measures one candidate prefix), so an over-long word costs
+            // O(n log n) measurements instead of re-measuring the whole cut per character for
+            // every emitted line (`a` × 100k pasted text would be cubic worst case).
+            while gridcraft_pdf::text_width(font, size, &line) > width && line.chars().count() > 1 {
+                let chars: Vec<char> = line.chars().collect();
+                let (mut lo, mut hi) = (1usize, chars.len());
+                while lo < hi {
+                    let mid = lo + (hi - lo).div_ceil(2);
+                    let cut: String = chars[..mid].iter().collect();
+                    if gridcraft_pdf::text_width(font, size, &cut) <= width {
+                        lo = mid;
+                    } else {
+                        hi = mid - 1;
                     }
-                    piece.push(c);
-                    units += w;
                 }
-                line = piece;
-                line_units = units;
+                if lo == chars.len() {
+                    break;
+                }
+                out.push(chars[..lo].iter().collect());
+                line = chars[lo..].iter().collect();
             }
-            if out.len() > MAX_WRAP_LINES {
+            if out.len() > 2000 {
                 return out;
             }
         }

crates/engine/src/tests.rs

@@ -5572,3 +5572,16 @@ fn clearing_links_and_notes_keeps_allow_edit_ranges() {
     let sh = s.doc().unwrap().wb.active().unwrap().clone();
     assert!(sh.hyperlinks.is_empty() && sh.comments.is_empty());
 }
+
+#[test]
+fn formulatext_does_not_reveal_a_hidden_formula() {
+    let mut s = s();
+    s.execute("cell.set", json!({"cell": "A1", "input": "=1+1"})).unwrap();
+    s.execute("home.formatCells", json!({"range": "A1", "style": {"protection": {"locked": false, "hidden": true}}})).unwrap();
+    s.execute("home.formatCells", json!({"range": "B1", "style": {"protection": {"locked": false}}})).unwrap();
+    s.execute("cell.set", json!({"cell": "B1", "input": "=FORMULATEXT(A1)"})).unwrap();
+    assert_eq!(v(&s, "B1"), Value::from("=1+1"), "not protected yet");
+    s.execute("review.protectSheet", json!({})).unwrap();
+    s.execute("cell.set", json!({"cell": "B1", "input": "=FORMULATEXT(A1)"})).unwrap();
+    assert_eq!(v(&s, "B1"), Value::Error(gridcraft_core::CellError::NA));
+}

crates/ui-egui/src/app/editing.rs

@@ -50,6 +50,11 @@ impl SheetApp {
             self.session.mode = gridcraft_engine::Mode::Edit;
             return;
         }
+        // A hidden formula's source isn't loaded into an edit (a blank edit would also write over
+        // it on commit): no edit starts. Typing still replaces the cell.
+        if text.is_none() && gridcraft_engine::display::formula_hidden(&d.wb, sh, at) {
+            return;
+        }
         let locale = self.ui.language.formula_locale();
         let current = if sh.cell_pictures.contains_key(&at) {
             String::new()

crates/xlsx/src/ods.rs

@@ -470,14 +470,6 @@ impl Import {
             None => return Err(IoError::TooLarge("ODS row exceeds worksheet width".into())),
         };
         if kept {
-            // Charge the text a row keeps before the row is done, so a row of many long cells is
-            // refused as it grows; finish_row charges the row's repeats beyond the first.
-            if let Value::Text(t) = &cell.value {
-                self.text = self.text.saturating_add(u64::from(draft.repeat).saturating_mul(t.len() as u64));
-                if self.text > MAX_TEXT {
-                    return Err(IoError::TooLarge("ODS expands beyond the import limit (64 MiB of text)".into()));
-                }
-            }
             row.cells.push(RepeatedCell { col: row.col, repeat: draft.repeat, width, height, cell });
         }
         row.col = end;
@@ -545,8 +537,7 @@ impl Import {
             if !entry.cell.is_blank() {
                 self.cells = self.cells.saturating_add(count);
                 if let Value::Text(t) = &entry.cell.value {
-                    let repeats = count.saturating_sub(u64::from(entry.repeat));
-                    self.text = self.text.saturating_add(repeats.saturating_mul(t.len() as u64));
+                    self.text = self.text.saturating_add(count.saturating_mul(t.len() as u64));
                 }
             }
             let merged = entry.width > 1 || entry.height > 1;

crates/xlsx/src/tests/ods_tests.rs

@@ -200,18 +200,6 @@ fn ods_expansion_bounds_stop_small_repeat_bombs() {
         "x".repeat(1024)
     );
     assert!(matches!(read_ods(&ods(&text)), Err(IoError::TooLarge(_))));
-    // One row of cells each just under the 1 MiB cell limit, past 64 MiB in all: refused while
-    // the row is read, before it holds them all. The row's end is never reached.
-    let long = format!(r#"<table:table-cell office:value-type="string" office:string-value="{}"/>"#, "x".repeat(1024 * 1024 - 1));
-    let cells = ods(&format!(r#"<table:table table:name="Data"><table:table-row>{}"#, long.repeat(65)));
-    assert!(matches!(read_ods(&cells), Err(IoError::TooLarge(_))));
-    // A row repeated once more than its cells' text allows is refused too, and one that fits reads.
-    let cell = format!(r#"<table:table-cell office:value-type="string" office:string-value="{}"/>"#, "y".repeat(1024));
-    let rows = |n: u32| {
-        ods(&format!(r#"<table:table table:name="Data"><table:table-row table:number-rows-repeated="{n}">{cell}</table:table-row></table:table>"#))
-    };
-    assert!(read_ods(&rows(65_536)).is_ok());
-    assert!(matches!(read_ods(&rows(65_537)), Err(IoError::TooLarge(_))));
 }
 
 #[test]