Unify layout of vec and cases with mat (#5934)

Co-authored-by: Laurenz <laurmaedje@gmail.com>

crates/typst-layout/src/math/accent.rs

@@ -19,9 +19,11 @@ pub fn layout_accent(
     let mut base = ctx.layout_into_fragment(&elem.base, styles.chain(&cramped))?;
 
     // Try to replace a glyph with its dotless variant.
+    if elem.dotless(styles) {
         if let MathFragment::Glyph(glyph) = &mut base {
             glyph.make_dotless_form(ctx);
         }
+    }
 
     // Preserve class to preserve automatic spacing.
     let base_class = base.class();

crates/typst-layout/src/math/mat.rs

@@ -1,4 +1,4 @@
-use typst_library::diag::{bail, SourceResult};
+use typst_library::diag::{bail, warning, SourceResult};
 use typst_library::foundations::{Content, Packed, Resolve, StyleChain};
 use typst_library::layout::{
     Abs, Axes, Em, FixedAlignment, Frame, FrameItem, Point, Ratio, Rel, Size,
@@ -9,7 +9,7 @@ use typst_library::visualize::{FillRule, FixedStroke, Geometry, LineCap, Shape};
 use typst_syntax::Span;
 
 use super::{
-    alignments, delimiter_alignment, stack, style_for_denominator, AlignmentResult,
+    alignments, delimiter_alignment, style_for_denominator, AlignmentResult,
     FrameFragment, GlyphFragment, LeftRightAlternator, MathContext, DELIM_SHORT_FALL,
 };
 
@@ -23,67 +23,23 @@ pub fn layout_vec(
     ctx: &mut MathContext,
     styles: StyleChain,
 ) -> SourceResult<()> {
-    let delim = elem.delim(styles);
-    let frame = layout_vec_body(
+    let span = elem.span();
+
+    let column: Vec<&Content> = elem.children.iter().collect();
+    let frame = layout_body(
         ctx,
         styles,
-        &elem.children,
+        &[column],
         elem.align(styles),
-        elem.gap(styles),
         LeftRightAlternator::Right,
+        None,
+        Axes::with_y(elem.gap(styles)),
+        span,
+        "elements",
     )?;
 
-    layout_delimiters(ctx, styles, frame, delim.open(), delim.close(), elem.span())
-}
-
-/// Lays out a [`MatElem`].
-#[typst_macros::time(name = "math.mat", span = elem.span())]
-pub fn layout_mat(
-    elem: &Packed<MatElem>,
-    ctx: &mut MathContext,
-    styles: StyleChain,
-) -> SourceResult<()> {
-    let augment = elem.augment(styles);
-    let rows = &elem.rows;
-
-    if let Some(aug) = &augment {
-        for &offset in &aug.hline.0 {
-            if offset == 0 || offset.unsigned_abs() >= rows.len() {
-                bail!(
-                    elem.span(),
-                    "cannot draw a horizontal line after row {} of a matrix with {} rows",
-                    if offset < 0 { rows.len() as isize + offset } else { offset },
-                    rows.len()
-                );
-            }
-        }
-
-        let ncols = rows.first().map_or(0, |row| row.len());
-
-        for &offset in &aug.vline.0 {
-            if offset == 0 || offset.unsigned_abs() >= ncols {
-                bail!(
-                        elem.span(),
-                        "cannot draw a vertical line after column {} of a matrix with {} columns",
-                        if offset < 0 { ncols as isize + offset } else { offset },
-                        ncols
-                    );
-            }
-        }
-    }
-
     let delim = elem.delim(styles);
-    let frame = layout_mat_body(
-        ctx,
-        styles,
-        rows,
-        elem.align(styles),
-        augment,
-        Axes::new(elem.column_gap(styles), elem.row_gap(styles)),
-        elem.span(),
-    )?;
-
-    layout_delimiters(ctx, styles, frame, delim.open(), delim.close(), elem.span())
+    layout_delimiters(ctx, styles, frame, delim.open(), delim.close(), span)
 }
 
 /// Lays out a [`CasesElem`].
@@ -93,60 +49,100 @@ pub fn layout_cases(
     ctx: &mut MathContext,
     styles: StyleChain,
 ) -> SourceResult<()> {
-    let delim = elem.delim(styles);
-    let frame = layout_vec_body(
+    let span = elem.span();
+
+    let column: Vec<&Content> = elem.children.iter().collect();
+    let frame = layout_body(
         ctx,
         styles,
-        &elem.children,
+        &[column],
         FixedAlignment::Start,
-        elem.gap(styles),
         LeftRightAlternator::None,
+        None,
+        Axes::with_y(elem.gap(styles)),
+        span,
+        "branches",
     )?;
 
+    let delim = elem.delim(styles);
     let (open, close) =
         if elem.reverse(styles) { (None, delim.close()) } else { (delim.open(), None) };
-
-    layout_delimiters(ctx, styles, frame, open, close, elem.span())
+    layout_delimiters(ctx, styles, frame, open, close, span)
 }
 
-/// Layout the inner contents of a vector.
-fn layout_vec_body(
+/// Lays out a [`MatElem`].
+#[typst_macros::time(name = "math.mat", span = elem.span())]
+pub fn layout_mat(
+    elem: &Packed<MatElem>,
     ctx: &mut MathContext,
     styles: StyleChain,
-    column: &[Content],
+) -> SourceResult<()> {
+    let span = elem.span();
+    let rows = &elem.rows;
+    let ncols = rows.first().map_or(0, |row| row.len());
+
+    let augment = elem.augment(styles);
+    if let Some(aug) = &augment {
+        for &offset in &aug.hline.0 {
+            if offset == 0 || offset.unsigned_abs() >= rows.len() {
+                bail!(
+                    span,
+                    "cannot draw a horizontal line after row {} of a matrix with {} rows",
+                    if offset < 0 { rows.len() as isize + offset } else { offset },
+                    rows.len()
+                );
+            }
+        }
+
+        for &offset in &aug.vline.0 {
+            if offset == 0 || offset.unsigned_abs() >= ncols {
+                bail!(
+                    span,
+                    "cannot draw a vertical line after column {} of a matrix with {} columns",
+                    if offset < 0 { ncols as isize + offset } else { offset },
+                    ncols
+                );
+            }
+        }
+    }
+
+    // Transpose rows of the matrix into columns.
+    let mut row_iters: Vec<_> = rows.iter().map(|i| i.iter()).collect();
+    let columns: Vec<Vec<_>> = (0..ncols)
+        .map(|_| row_iters.iter_mut().map(|i| i.next().unwrap()).collect())
+        .collect();
+
+    let frame = layout_body(
+        ctx,
+        styles,
+        &columns,
+        elem.align(styles),
+        LeftRightAlternator::Right,
+        augment,
+        Axes::new(elem.column_gap(styles), elem.row_gap(styles)),
+        span,
+        "cells",
+    )?;
+
+    let delim = elem.delim(styles);
+    layout_delimiters(ctx, styles, frame, delim.open(), delim.close(), span)
+}
+
+/// Layout the inner contents of a matrix, vector, or cases.
+#[allow(clippy::too_many_arguments)]
+fn layout_body(
+    ctx: &mut MathContext,
+    styles: StyleChain,
+    columns: &[Vec<&Content>],
     align: FixedAlignment,
-    row_gap: Rel<Abs>,
     alternator: LeftRightAlternator,
-) -> SourceResult<Frame> {
-    let gap = row_gap.relative_to(ctx.region.size.y);
-
-    let denom_style = style_for_denominator(styles);
-    let mut flat = vec![];
-    for child in column {
-        // We allow linebreaks in cases and vectors, which are functionally
-        // identical to commas.
-        flat.extend(ctx.layout_into_run(child, styles.chain(&denom_style))?.rows());
-    }
-    // We pad ascent and descent with the ascent and descent of the paren
-    // to ensure that normal vectors are aligned with others unless they are
-    // way too big.
-    let paren =
-        GlyphFragment::new(ctx, styles.chain(&denom_style), '(', Span::detached());
-    Ok(stack(flat, align, gap, 0, alternator, Some((paren.ascent, paren.descent))))
-}
-
-/// Layout the inner contents of a matrix.
-fn layout_mat_body(
-    ctx: &mut MathContext,
-    styles: StyleChain,
-    rows: &[Vec<Content>],
-    align: FixedAlignment,
     augment: Option<Augment<Abs>>,
     gap: Axes<Rel<Abs>>,
     span: Span,
+    children: &str,
 ) -> SourceResult<Frame> {
-    let ncols = rows.first().map_or(0, |row| row.len());
-    let nrows = rows.len();
+    let nrows = columns.first().map_or(0, |col| col.len());
+    let ncols = columns.len();
     if ncols == 0 || nrows == 0 {
         return Ok(Frame::soft(Size::zero()));
     }
@@ -178,16 +174,11 @@ fn layout_mat_body(
     // Before the full matrix body can be laid out, the
     // individual cells must first be independently laid out
     // so we can ensure alignment across rows and columns.
+    let mut cols = vec![vec![]; ncols];
 
     // This variable stores the maximum ascent and descent for each row.
     let mut heights = vec![(Abs::zero(), Abs::zero()); nrows];
 
-    // We want to transpose our data layout to columns
-    // before final layout. For efficiency, the columns
-    // variable is set up here and newly generated
-    // individual cells are then added to it.
-    let mut cols = vec![vec![]; ncols];
-
     let denom_style = style_for_denominator(styles);
     // We pad ascent and descent with the ascent and descent of the paren
     // to ensure that normal matrices are aligned with others unless they are
@@ -195,10 +186,22 @@ fn layout_mat_body(
     let paren =
         GlyphFragment::new(ctx, styles.chain(&denom_style), '(', Span::detached());
 
-    for (row, (ascent, descent)) in rows.iter().zip(&mut heights) {
-        for (cell, col) in row.iter().zip(&mut cols) {
+    for (column, col) in columns.iter().zip(&mut cols) {
+        for (cell, (ascent, descent)) in column.iter().zip(&mut heights) {
+            let cell_span = cell.span();
             let cell = ctx.layout_into_run(cell, styles.chain(&denom_style))?;
 
+            // We ignore linebreaks in the cells as we can't differentiate
+            // alignment points for the whole body from ones for a specific
+            // cell, and multiline cells don't quite make sense at the moment.
+            if cell.is_multiline() {
+                ctx.engine.sink.warn(warning!(
+                   cell_span,
+                   "linebreaks are ignored in {}", children;
+                   hint: "use commas instead to separate each line"
+                ));
+            }
+
             ascent.set_max(cell.ascent().max(paren.ascent));
             descent.set_max(cell.descent().max(paren.descent));
 
@@ -222,7 +225,7 @@ fn layout_mat_body(
         let mut y = Abs::zero();
 
         for (cell, &(ascent, descent)) in col.into_iter().zip(&heights) {
-            let cell = cell.into_line_frame(&points, LeftRightAlternator::Right);
+            let cell = cell.into_line_frame(&points, alternator);
             let pos = Point::new(
                 if points.is_empty() {
                     x + align.position(rcol - cell.width())

crates/typst-layout/src/math/shared.rs

@@ -117,7 +117,6 @@ pub fn stack(
     gap: Abs,
     baseline: usize,
     alternator: LeftRightAlternator,
-    minimum_ascent_descent: Option<(Abs, Abs)>,
 ) -> Frame {
     let AlignmentResult { points, width } = alignments(&rows);
     let rows: Vec<_> = rows
@@ -125,13 +124,9 @@ pub fn stack(
         .map(|row| row.into_line_frame(&points, alternator))
         .collect();
 
-    let padded_height = |height: Abs| {
-        height.max(minimum_ascent_descent.map_or(Abs::zero(), |(a, d)| a + d))
-    };
-
     let mut frame = Frame::soft(Size::new(
         width,
-        rows.iter().map(|row| padded_height(row.height())).sum::<Abs>()
+        rows.iter().map(|row| row.height()).sum::<Abs>()
             + rows.len().saturating_sub(1) as f64 * gap,
     ));
 
@@ -142,14 +137,11 @@ pub fn stack(
         } else {
             Abs::zero()
         };
-        let ascent_padded_part = minimum_ascent_descent
-            .map_or(Abs::zero(), |(a, _)| (a - row.ascent()))
-            .max(Abs::zero());
-        let pos = Point::new(x, y + ascent_padded_part);
+        let pos = Point::new(x, y);
         if i == baseline {
-            frame.set_baseline(y + row.baseline() + ascent_padded_part);
+            frame.set_baseline(y + row.baseline());
         }
-        y += padded_height(row.height()) + gap;
+        y += row.height() + gap;
         frame.push_frame(pos, row);
     }
 

crates/typst-layout/src/math/underover.rs

@@ -312,14 +312,8 @@ fn layout_underoverspreader(
         }
     };
 
-    let frame = stack(
-        rows,
-        FixedAlignment::Center,
-        gap,
-        baseline,
-        LeftRightAlternator::Right,
-        None,
-    );
+    let frame =
+        stack(rows, FixedAlignment::Center, gap, baseline, LeftRightAlternator::Right);
     ctx.push(FrameFragment::new(styles, frame).with_class(body_class));
 
     Ok(())

crates/typst-library/src/foundations/array.rs

@@ -172,17 +172,29 @@ impl Array {
     }
 
     /// Returns the first item in the array. May be used on the left-hand side
-    /// of an assignment. Fails with an error if the array is empty.
+    /// an assignment. Returns the default value if the array is empty
+    /// or fails with an error is no default value was specified.
     #[func]
-    pub fn first(&self) -> StrResult<Value> {
-        self.0.first().cloned().ok_or_else(array_is_empty)
+    pub fn first(
+        &self,
+        /// A default value to return if the array is empty.
+        #[named]
+        default: Option<Value>,
+    ) -> StrResult<Value> {
+        self.0.first().cloned().or(default).ok_or_else(array_is_empty)
     }
 
     /// Returns the last item in the array. May be used on the left-hand side of
-    /// an assignment. Fails with an error if the array is empty.
+    /// an assignment. Returns the default value if the array is empty
+    /// or fails with an error is no default value was specified.
     #[func]
-    pub fn last(&self) -> StrResult<Value> {
-        self.0.last().cloned().ok_or_else(array_is_empty)
+    pub fn last(
+        &self,
+        /// A default value to return if the array is empty.
+        #[named]
+        default: Option<Value>,
+    ) -> StrResult<Value> {
+        self.0.last().cloned().or(default).ok_or_else(array_is_empty)
     }
 
     /// Returns the item at the specified index in the array. May be used on the

crates/typst-library/src/math/accent.rs

@@ -13,8 +13,8 @@ use crate::math::Mathy;
 /// ```
 #[elem(Mathy)]
 pub struct AccentElem {
-    /// The base to which the accent is applied.
-    /// May consist of multiple letters.
+    /// The base to which the accent is applied. May consist of multiple
+    /// letters.
     ///
     /// ```example
     /// $arrow(A B C)$
@@ -51,9 +51,24 @@ pub struct AccentElem {
     pub accent: Accent,
 
     /// The size of the accent, relative to the width of the base.
+    ///
+    /// ```example
+    /// $dash(A, size: #150%)$
+    /// ```
     #[resolve]
     #[default(Rel::one())]
     pub size: Rel<Length>,
+
+    /// Whether to remove the dot on top of lowercase i and j when adding a top
+    /// accent.
+    ///
+    /// This enables the `dtls` OpenType feature.
+    ///
+    /// ```example
+    /// $hat(dotless: #false, i)$
+    /// ```
+    #[default(true)]
+    pub dotless: bool,
 }
 
 /// An accent character.
@@ -103,11 +118,18 @@ macro_rules! accents {
                 /// The size of the accent, relative to the width of the base.
                 #[named]
                 size: Option<Rel<Length>>,
+                /// Whether to remove the dot on top of lowercase i and j when
+                /// adding a top accent.
+                #[named]
+                dotless: Option<bool>,
             ) -> Content {
                 let mut accent = AccentElem::new(base, Accent::new($primary));
                 if let Some(size) = size {
                     accent = accent.with_size(size);
                 }
+                if let Some(dotless) = dotless {
+                    accent = accent.with_dotless(dotless);
+                }
                 accent.pack()
             }
         )+

crates/typst-library/src/text/smartquote.rs

@@ -238,7 +238,7 @@ impl<'s> SmartQuotes<'s> {
             "cs" | "de" | "et" | "is" | "lt" | "lv" | "sk" | "sl" => low_high,
             "da" => ("‘", "’", "“", "”"),
             "fr" | "ru" if alternative => default,
-            "fr" => ("‹\u{00A0}", "\u{00A0}›", "«\u{00A0}", "\u{00A0}»"),
+            "fr" => ("“", "”", "«\u{202F}", "\u{202F}»"),
             "fi" | "sv" if alternative => ("’", "’", "»", "»"),
             "bs" | "fi" | "sv" => ("’", "’", "”", "”"),
             "it" if alternative => default,

tests/suite/foundations/array.typ

@@ -179,6 +179,10 @@
 #test((2,).last(), 2)
 #test((1, 2, 3).first(), 1)
 #test((1, 2, 3).last(), 3)
+#test((1, 2).first(default: 99), 1)
+#test(().first(default: 99), 99)
+#test((1, 2).last(default: 99), 2)
+#test(().last(default: 99), 99)
 
 --- array-first-empty ---
 // Error: 2-12 array is empty

tests/suite/math/accent.typ

@@ -42,3 +42,11 @@ $tilde(U, size: #1.1em), x^tilde(U, size: #1.1em), sscript(tilde(U, size: #1.1em
   macron(bb(#c)), dot(cal(#c)), diaer(upright(#c)), breve(bold(#c)),
   circle(bold(upright(#c))), caron(upright(sans(#c))), arrow(bold(frak(#c)))$
 $test(i) \ test(j)$
+
+--- math-accent-dotless-disabled ---
+// Test disabling the dotless glyph variants.
+$hat(i), hat(i, dotless: #false), accent(j, tilde), accent(j, tilde, dotless: #false)$
+
+--- math-accent-dotless-set-rule ---
+#set math.accent(dotless: false)
+$ hat(i) $

tests/suite/math/cases.typ

@@ -17,6 +17,6 @@ $ x = cases(1, 2) $
 $ cases(a, b, c) $
 
 --- math-cases-linebreaks ---
-// Currently linebreaks are equivalent to commas, though this behaviour may
-// change in the future.
+// Warning: 40-49 linebreaks are ignored in branches
+// Hint: 40-49 use commas instead to separate each line
 $ cases(a, b, c) cases(reverse: #true, a \ b \ c) $

tests/suite/math/mat.typ

@@ -256,10 +256,17 @@ $ mat(delim: #(none, "["), 1, 2; 3, 4) $
 $ mat(delim: #(sym.angle.r, sym.bracket.double.r), 1, 2; 3, 4) $
 
 --- math-mat-linebreaks ---
-// Unlike cases and vectors, linebreaks are discarded in matrices. This
-// behaviour may change in the future.
+// Warning: 20-29 linebreaks are ignored in cells
+// Hint: 20-29 use commas instead to separate each line
 $ mat(a; b; c) mat(a \ b \ c) $
 
+--- math-mat-vec-cases-unity ---
+// Test that matrices, vectors, and cases are all laid out the same.
+$ mat(z_(n_p); a^2)
+  vec(z_(n_p), a^2) 
+  cases(reverse: #true, delim: \(, z_(n_p), a^2)
+  cases(delim: \(, z_(n_p), a^2) $
+
 --- issue-1617-mat-align ---
 #set page(width: auto)
 $ mat(a, b; c, d) mat(x; y) $

tests/suite/math/vec.typ

@@ -51,6 +51,6 @@ $ vec(1, 2) $
 #set math.vec(delim: (none, "%"))
 
 --- math-vec-linebreaks ---
-// Currently linebreaks are equivalent to commas, though this behaviour may
-// change in the future.
+// Warning: 20-29 linebreaks are ignored in elements
+// Hint: 20-29 use commas instead to separate each line
 $ vec(a, b, c) vec(a \ b \ c) $

tests/suite/text/smartquote.typ

@@ -99,7 +99,7 @@ He's told some books contain questionable "example text".
 
 --- smartquote-disabled-temporarily ---
 // Test changing properties within text.
-"She suddenly started speaking french: #text(lang: "fr")['Je suis une banane.']" Roman told me.
+"She suddenly started speaking french: #text(lang: "fr", region: "CH")['Je suis une banane.']" Roman told me.
 
 Some people's thought on this would be #[#set smartquote(enabled: false); "strange."]