Extract Run struct

crates/typst-layout/src/inline/line.rs

@@ -270,12 +270,13 @@ fn collect_range<'a>(
     items: &mut Items<'a>,
     fallback: &mut Option<ItemEntry<'a>>,
 ) {
-    for (subrange, item) in p.slice(range.clone()) {
+    for run in p.slice(range.clone()) {
         // All non-text items are just kept, they can't be split.
-        let Item::Text(shaped) = item else {
+        let Item::Text(shaped) = &run.item else {
-            items.push(item);
+            items.push(&run.item);
             continue;
         };
+        let subrange = &run.range;
 
         // The intersection range of the item, the subrange, and the line's
         // trimming.
@@ -296,7 +297,7 @@ fn collect_range<'a>(
             items.push(Item::Text(reshaped));
         } else {
             // When the item is fully contained, just keep it.
-            items.push(item);
+            items.push(&run.item);
         }
     }
 }

crates/typst-layout/src/inline/linebreak.rs

@@ -823,8 +823,8 @@ fn linebreak_link(link: &str, mut f: impl FnMut(usize)) {
 /// Whether hyphenation is enabled at the given offset.
 fn hyphenate_at(p: &Preparation, offset: usize) -> bool {
     p.config.hyphenate.unwrap_or_else(|| {
-        let (_, item) = p.get(offset);
+        let run = p.get(offset);
-        match item.text() {
+        match run.item.text() {
             Some(text) => TextElem::hyphenate_in(text.styles).unwrap_or(p.config.justify),
             None => false,
         }
@@ -834,8 +834,8 @@ fn hyphenate_at(p: &Preparation, offset: usize) -> bool {
 /// The text language at the given offset.
 fn lang_at(p: &Preparation, offset: usize) -> Option<hypher::Lang> {
     let lang = p.config.lang.or_else(|| {
-        let (_, item) = p.get(offset);
+        let run = p.get(offset);
-        let styles = item.text()?.styles;
+        let styles = run.item.text()?.styles;
         Some(TextElem::lang_in(styles))
     })?;
 
@@ -900,8 +900,8 @@ impl Estimates {
         let mut shrinkability = CumulativeVec::with_capacity(cap);
         let mut justifiables = CumulativeVec::with_capacity(cap);
 
-        for (range, item) in p.items.iter() {
+        for run in p.items.iter() {
-            if let Item::Text(shaped) = item {
+            if let Item::Text(shaped) = &run.item {
                 for g in shaped.glyphs.iter() {
                     let byte_len = g.range.len();
                     let stretch = g.stretchability().0 + g.stretchability().1;
@@ -912,13 +912,13 @@ impl Estimates {
                     justifiables.push(byte_len, g.is_justifiable() as usize);
                 }
             } else {
-                widths.push(range.len(), item.natural_width());
+                widths.push(run.range.len(), run.item.natural_width());
             }
 
-            widths.adjust(range.end);
+            widths.adjust(run.range.end);
-            stretchability.adjust(range.end);
+            stretchability.adjust(run.range.end);
-            shrinkability.adjust(range.end);
+            shrinkability.adjust(run.range.end);
-            justifiables.adjust(range.end);
+            justifiables.adjust(run.range.end);
         }
 
         Self {

crates/typst-layout/src/inline/prepare.rs

@@ -3,6 +3,12 @@ use unicode_bidi::{BidiInfo, Level as BidiLevel};
 
 use super::*;
 
+#[derive(Debug)]
+pub struct Run<'a> {
+    pub item: Item<'a>,
+    pub range: Range,
+}
+
 /// A representation in which children are already layouted and text is already
 /// preshaped.
 ///
@@ -20,7 +26,7 @@ pub struct Preparation<'a> {
     /// direction).
     pub bidi: Option<BidiInfo<'a>>,
     /// Text runs, spacing and layouted elements.
-    pub items: Vec<(Range, Item<'a>)>,
+    pub items: Vec<Run<'a>>,
     /// Maps from byte indices to item indices.
     pub indices: Vec<usize>,
     /// The span mapper.
@@ -29,13 +35,13 @@ pub struct Preparation<'a> {
 
 impl<'a> Preparation<'a> {
     /// Get the item that contains the given `text_offset`.
-    pub fn get(&self, offset: usize) -> &(Range, Item<'a>) {
+    pub fn get(&self, offset: usize) -> &Run {
         let idx = self.indices.get(offset).copied().unwrap_or(0);
         &self.items[idx]
     }
 
     /// Iterate over the items that intersect the given `sliced` range.
-    pub fn slice(&self, sliced: Range) -> impl Iterator<Item = &(Range, Item<'a>)> {
+    pub fn slice(&self, sliced: Range) -> impl Iterator<Item = &Run> {
         // Usually, we don't want empty-range items at the start of the line
         // (because they will be part of the previous line), but for the first
         // line, we need to keep them.
@@ -43,8 +49,8 @@ impl<'a> Preparation<'a> {
             0 => 0,
             n => self.indices.get(n).copied().unwrap_or(0),
         };
-        self.items[start..].iter().take_while(move |(range, _)| {
+        self.items[start..].iter().take_while(move |run| {
-            range.start < sliced.end || range.end <= sliced.end
+            run.range.start < sliced.end || run.range.end <= sliced.end
         })
     }
 }
@@ -84,7 +90,7 @@ pub fn prepare<'a>(
             Segment::Text(_, styles) => {
                 shape_range(&mut items, engine, text, &bidi, range, styles);
             }
-            Segment::Item(item) => items.push((range, item)),
+            Segment::Item(item) => items.push(Run { range, item }),
         }
 
         cursor = end;
@@ -92,8 +98,8 @@ pub fn prepare<'a>(
 
     // Build the mapping from byte to item indices.
     let mut indices = Vec::with_capacity(text.len());
-    for (i, (range, _)) in items.iter().enumerate() {
+    for (i, run) in items.iter().enumerate() {
-        indices.extend(range.clone().map(|_| i));
+        indices.extend(run.range.clone().map(|_| i));
     }
 
     if config.cjk_latin_spacing {
@@ -113,15 +119,15 @@ pub fn prepare<'a>(
 /// Add some spacing between Han characters and western characters. See
 /// Requirements for Chinese Text Layout, Section 3.2.2 Mixed Text Composition
 /// in Horizontal Written Mode
-fn add_cjk_latin_spacing(items: &mut [(Range, Item)]) {
+fn add_cjk_latin_spacing(items: &mut [Run]) {
     let mut items = items
         .iter_mut()
-        .filter(|(_, x)| !matches!(x, Item::Tag(_)))
+        .filter(|run| !matches!(run.item, Item::Tag(_)))
         .peekable();
 
     let mut prev: Option<&ShapedGlyph> = None;
-    while let Some((_, item)) = items.next() {
+    while let Some(run) = items.next() {
-        let Some(text) = item.text_mut() else {
+        let Some(text) = run.item.text_mut() else {
             prev = None;
             continue;
         };
@@ -135,7 +141,7 @@ fn add_cjk_latin_spacing(items: &mut [(Range, Item)]) {
             let next = glyphs.peek().map(|n| n as _).or_else(|| {
                 items
                     .peek()
-                    .and_then(|(_, i)| i.text())
+                    .and_then(|run| run.item.text())
                     .and_then(|shaped| shaped.glyphs.first())
             });
 

crates/typst-layout/src/inline/shaping.rs

@@ -19,6 +19,7 @@ use typst_utils::SliceExt;
 use unicode_bidi::{BidiInfo, Level as BidiLevel};
 use unicode_script::{Script, UnicodeScript};
 
+use super::prepare::Run;
 use super::{decorate, Item, Range, SpanMapper};
 use crate::modifiers::{FrameModifiers, FrameModify};
 
@@ -592,7 +593,7 @@ impl Debug for ShapedText<'_> {
 /// Group a range of text by BiDi level and script, shape the runs and generate
 /// items for them.
 pub fn shape_range<'a>(
-    items: &mut Vec<(Range, Item<'a>)>,
+    items: &mut Vec<Run<'a>>,
     engine: &Engine,
     text: &'a str,
     bidi: &BidiInfo<'a>,
@@ -606,7 +607,7 @@ pub fn shape_range<'a>(
         let dir = if level.is_ltr() { Dir::LTR } else { Dir::RTL };
         let shaped =
             shape(engine, range.start, &text[range.clone()], styles, dir, lang, region);
-        items.push((range, Item::Text(shaped)));
+        items.push(Run { range, item: Item::Text(shaped) });
     };
 
     let mut prev_level = BidiLevel::ltr();