Add remaining height example for layout (#6266)

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

crates/typst-eval/src/call.rs

@@ -37,7 +37,12 @@ impl Eval for ast::FuncCall<'_> {
             let target = access.target();
             let field = access.field();
             match eval_field_call(target, field, args, span, vm)? {
-                FieldCall::Normal(callee, args) => (callee, args),
+                FieldCall::Normal(callee, args) => {
+                    if vm.inspected == Some(callee_span) {
+                        vm.trace(callee.clone());
+                    }
+                    (callee, args)
+                }
                 FieldCall::Resolved(value) => return Ok(value),
             }
         } else {

crates/typst-ide/src/complete.rs

@@ -15,7 +15,7 @@ use typst::syntax::{
     ast, is_id_continue, is_id_start, is_ident, FileId, LinkedNode, Side, Source,
     SyntaxKind,
 };
-use typst::text::RawElem;
+use typst::text::{FontFlags, RawElem};
 use typst::visualize::Color;
 use unscanny::Scanner;
 
@@ -1081,6 +1081,24 @@ fn code_completions(ctx: &mut CompletionContext, hash: bool) {
     }
 }
 
+/// See if the AST node is somewhere within a show rule applying to equations
+fn is_in_equation_show_rule(leaf: &LinkedNode<'_>) -> bool {
+    let mut node = leaf;
+    while let Some(parent) = node.parent() {
+        if_chain! {
+            if let Some(expr) = parent.get().cast::<ast::Expr>();
+            if let ast::Expr::ShowRule(show) = expr;
+            if let Some(ast::Expr::FieldAccess(field)) = show.selector();
+            if field.field().as_str() == "equation";
+            then {
+                return true;
+            }
+        }
+        node = parent;
+    }
+    false
+}
+
 /// Context for autocompletion.
 struct CompletionContext<'a> {
     world: &'a (dyn IdeWorld + 'a),
@@ -1152,10 +1170,12 @@ impl<'a> CompletionContext<'a> {
 
     /// Add completions for all font families.
     fn font_completions(&mut self) {
-        let equation = self.before_window(25).contains("equation");
+        let equation = is_in_equation_show_rule(self.leaf);
         for (family, iter) in self.world.book().families() {
-            let detail = summarize_font_family(iter);
-            if !equation || family.contains("Math") {
+            let variants: Vec<_> = iter.collect();
+            let is_math = variants.iter().any(|f| f.flags.contains(FontFlags::MATH));
+            let detail = summarize_font_family(variants);
+            if !equation || is_math {
                 self.str_completion(
                     family,
                     Some(CompletionKind::Font),
@@ -1790,4 +1810,21 @@ mod tests {
             .must_include(["r", "dashed"])
             .must_exclude(["cases"]);
     }
+
+    #[test]
+    fn test_autocomplete_fonts() {
+        test("#text(font:)", -1)
+            .must_include(["\"Libertinus Serif\"", "\"New Computer Modern Math\""]);
+
+        test("#show link: set text(font: )", -1)
+            .must_include(["\"Libertinus Serif\"", "\"New Computer Modern Math\""]);
+
+        test("#show math.equation: set text(font: )", -1)
+            .must_include(["\"New Computer Modern Math\""])
+            .must_exclude(["\"Libertinus Serif\""]);
+
+        test("#show math.equation: it => { set text(font: )\nit }", -6)
+            .must_include(["\"New Computer Modern Math\""])
+            .must_exclude(["\"Libertinus Serif\""]);
+    }
 }

crates/typst-ide/src/tooltip.rs

@@ -269,7 +269,7 @@ fn font_tooltip(world: &dyn IdeWorld, leaf: &LinkedNode) -> Option<Tooltip> {
             .find(|&(family, _)| family.to_lowercase().as_str() == lower.as_str());
 
         then {
-            let detail = summarize_font_family(iter);
+            let detail = summarize_font_family(iter.collect());
             return Some(Tooltip::Text(detail));
         }
     };
@@ -371,4 +371,11 @@ mod tests {
         test(&world, -2, Side::Before).must_be_none();
         test(&world, -2, Side::After).must_be_text("This star imports `a`, `b`, and `c`");
     }
+
+    #[test]
+    fn test_tooltip_field_call() {
+        let world = TestWorld::new("#import \"other.typ\"\n#other.f()")
+            .with_source("other.typ", "#let f = (x) => 1");
+        test(&world, -4, Side::After).must_be_code("(..) => ..");
+    }
 }

crates/typst-ide/src/utils.rs

@@ -77,23 +77,20 @@ pub fn plain_docs_sentence(docs: &str) -> EcoString {
 }
 
 /// Create a short description of a font family.
-pub fn summarize_font_family<'a>(
-    variants: impl Iterator<Item = &'a FontInfo>,
-) -> EcoString {
-    let mut infos: Vec<_> = variants.collect();
-    infos.sort_by_key(|info| info.variant);
+pub fn summarize_font_family(mut variants: Vec<&FontInfo>) -> EcoString {
+    variants.sort_by_key(|info| info.variant);
 
     let mut has_italic = false;
     let mut min_weight = u16::MAX;
     let mut max_weight = 0;
-    for info in &infos {
+    for info in &variants {
         let weight = info.variant.weight.to_number();
         has_italic |= info.variant.style == FontStyle::Italic;
         min_weight = min_weight.min(weight);
         max_weight = min_weight.max(weight);
     }
 
-    let count = infos.len();
+    let count = variants.len();
     let mut detail = eco_format!("{count} variant{}.", if count == 1 { "" } else { "s" });
 
     if min_weight == max_weight {

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

@@ -278,6 +278,9 @@ impl MathRun {
         frame
     }
 
+    /// Convert this run of math fragments into a vector of inline items for
+    /// paragraph layout. Creates multiple fragments when relation or binary
+    /// operators are present to allow for line-breaking opportunities later.
     pub fn into_par_items(self) -> Vec<InlineItem> {
         let mut items = vec![];
 
@@ -295,21 +298,24 @@ impl MathRun {
 
         let mut space_is_visible = false;
 
-        let is_relation = |f: &MathFragment| matches!(f.class(), MathClass::Relation);
         let is_space = |f: &MathFragment| {
             matches!(f, MathFragment::Space(_) | MathFragment::Spacing(_, _))
         };
+        let is_line_break_opportunity = |class, next_fragment| match class {
+            // Don't split when two relations are in a row or when preceding a
+            // closing parenthesis.
+            MathClass::Binary => next_fragment != Some(MathClass::Closing),
+            MathClass::Relation => {
+                !matches!(next_fragment, Some(MathClass::Relation | MathClass::Closing))
+            }
+            _ => false,
+        };
 
         let mut iter = self.0.into_iter().peekable();
         while let Some(fragment) = iter.next() {
-            if space_is_visible {
-                match fragment {
-                    MathFragment::Space(width) | MathFragment::Spacing(width, _) => {
-                        items.push(InlineItem::Space(width, true));
-                        continue;
-                    }
-                    _ => {}
-                }
+            if space_is_visible && is_space(&fragment) {
+                items.push(InlineItem::Space(fragment.width(), true));
+                continue;
             }
 
             let class = fragment.class();
@@ -323,10 +329,9 @@ impl MathRun {
             frame.push_frame(pos, fragment.into_frame());
             empty = false;
 
-            if class == MathClass::Binary
-                || (class == MathClass::Relation
-                    && !iter.peek().map(is_relation).unwrap_or_default())
-            {
+            // Split our current frame when we encounter a binary operator or
+            // relation so that there is a line-breaking opportunity.
+            if is_line_break_opportunity(class, iter.peek().map(|f| f.class())) {
                 let mut frame_prev =
                     std::mem::replace(&mut frame, Frame::soft(Size::zero()));
 

crates/typst-library/src/layout/layout.rs

@@ -41,8 +41,23 @@ use crate::layout::{BlockElem, Size};
 /// receives the page's dimensions minus its margins. This is mostly useful in
 /// combination with [measurement]($measure).
 ///
-/// You can also use this function to resolve [`ratio`] to fixed lengths. This
-/// might come in handy if you're building your own layout abstractions.
+/// To retrieve the _remaining_ size of the page rather than its full size, you
+/// you can wrap your `layout` call in a `{block(height: 1fr)}`. This works
+/// because the block automatically grows to fill the remaining space (see the
+/// [fraction] documentation for more details).
+///
+/// ```example
+/// #set page(height: 150pt)
+///
+/// #lorem(20)
+///
+/// #block(height: 1fr, layout(size => [
+///   Remaining height: #size.height
+/// ]))
+/// ```
+///
+/// You can also use this function to resolve a [`ratio`] to a fixed length.
+/// This might come in handy if you're building your own layout abstractions.
 ///
 /// ```example
 /// #layout(size => {

crates/typst-library/src/model/reference.rs

@@ -21,9 +21,10 @@ use crate::text::TextElem;
 ///
 /// The default, a `{"normal"}` reference, produces a textual reference to a
 /// label. For example, a reference to a heading will yield an appropriate
-/// string such as "Section 1" for a reference to the first heading. The
-/// references are also links to the respective element. Reference syntax can
-/// also be used to [cite] from a bibliography.
+/// string such as "Section 1" for a reference to the first heading. The word
+/// "Section" depends on the [`lang`]($text.lang) setting and is localized
+/// accordingly. The references are also links to the respective element.
+/// Reference syntax can also be used to [cite] from a bibliography.
 ///
 /// As the default form requires a supplement and numbering, the label must be
 /// attached to a _referenceable element_. Referenceable elements include

crates/typst-library/src/text/font/book.rs

@@ -194,6 +194,8 @@ bitflags::bitflags! {
         const MONOSPACE = 1 << 0;
         /// Glyphs have short strokes at their stems.
         const SERIF = 1 << 1;
+        /// Font face has a MATH table
+        const MATH = 1 << 2;
     }
 }
 
@@ -272,6 +274,7 @@ impl FontInfo {
 
         let mut flags = FontFlags::empty();
         flags.set(FontFlags::MONOSPACE, ttf.is_monospaced());
+        flags.set(FontFlags::MATH, ttf.tables().math.is_some());
 
         // Determine whether this is a serif or sans-serif font.
         if let Some(panose) = ttf

tests/suite/math/multiline.typ

@@ -99,6 +99,9 @@ Multiple trailing line breaks.
 #let hrule(x) = box(line(length: x))
 #hrule(90pt)$<;$\
 #hrule(95pt)$<;$\
+// We don't linebreak before a closing paren, but do before an opening paren.
+#hrule(90pt)$<($\
+#hrule(95pt)$<($
 #hrule(90pt)$<)$\
 #hrule(95pt)$<)$