Needless clone, borrows, casts and lifetimes (#504)

cli/src/main.rs

@@ -279,7 +279,7 @@ fn compile_once(world: &mut SystemWorld, command: &CompileSettings) -> StrResult
         // Print diagnostics.
         Err(errors) => {
             status(command, Status::Error).unwrap();
-            print_diagnostics(&world, *errors)
+            print_diagnostics(world, *errors)
                 .map_err(|_| "failed to print diagnostics")?;
             Ok(true)
         }
@@ -576,10 +576,10 @@ impl PathHash {
 /// Read a file.
 fn read(path: &Path) -> FileResult<Vec<u8>> {
     let f = |e| FileError::from_io(e, path);
-    if fs::metadata(&path).map_err(f)?.is_dir() {
+    if fs::metadata(path).map_err(f)?.is_dir() {
         Err(FileError::IsDirectory)
     } else {
-        fs::read(&path).map_err(f)
+        fs::read(path).map_err(f)
     }
 }
 

library/src/compute/calc.rs

@@ -457,7 +457,7 @@ pub fn round(
         Num::Int(n) if digits == 0 => Value::Int(n),
         _ => {
             let n = value.float();
-            let factor = 10.0_f64.powi(digits as i32) as f64;
+            let factor = 10.0_f64.powi(digits as i32);
             Value::Float((n * factor).round() / factor)
         }
     }

library/src/layout/flow.rs

@@ -30,7 +30,7 @@ impl Layout for FlowElem {
             let mut styles = styles;
             if let Some((elem, map)) = child.to_styled() {
                 child = elem;
-                styles = outer.chain(&map);
+                styles = outer.chain(map);
             }
 
             if let Some(elem) = child.to::<VElem>() {
@@ -54,7 +54,7 @@ impl Layout for FlowElem {
                     true,
                 ));
             } else if child.can::<dyn Layout>() {
-                layouter.layout_multiple(vt, &child, styles)?;
+                layouter.layout_multiple(vt, child, styles)?;
             } else if child.is::<ColbreakElem>() {
                 if !layouter.regions.backlog.is_empty() || layouter.regions.last.is_some()
                 {

library/src/layout/fragment.rs

@@ -15,6 +15,11 @@ impl Fragment {
         Self(frames)
     }
 
+    /// Return `true` if the length is 0.
+    pub fn is_empty(&self) -> bool {
+        self.0.is_empty()
+    }
+
     /// The number of frames in the fragment.
     pub fn len(&self) -> usize {
         self.0.len()

library/src/layout/grid.rs

@@ -267,7 +267,7 @@ impl<'a, 'v> GridLayouter<'a, 'v> {
 
         // We use these regions for auto row measurement. Since at that moment,
         // columns are already sized, we can enable horizontal expansion.
-        let mut regions = regions.clone();
+        let mut regions = regions;
         regions.expand = Axes::new(true, false);
 
         Self {

library/src/layout/list.rs

@@ -197,7 +197,7 @@ cast_from_value! {
     ListMarker,
     v: Content => Self::Content(vec![v]),
     array: Array => {
-        if array.len() == 0 {
+        if array.is_empty() {
             Err("array must contain at least one marker")?;
         }
         Self::Content(array.into_iter().map(Value::display).collect())

library/src/layout/mod.rs

@@ -172,7 +172,7 @@ fn realize_root<'a>(
         return Ok((content.clone(), styles));
     }
 
-    let mut builder = Builder::new(vt, &scratch, true);
+    let mut builder = Builder::new(vt, scratch, true);
     builder.accept(content, styles)?;
     builder.interrupt_page(Some(styles))?;
     let (pages, shared) = builder.doc.unwrap().pages.finish();
@@ -197,7 +197,7 @@ fn realize_block<'a>(
         return Ok((content.clone(), styles));
     }
 
-    let mut builder = Builder::new(vt, &scratch, false);
+    let mut builder = Builder::new(vt, scratch, false);
     builder.accept(content, styles)?;
     builder.interrupt_par()?;
     let (children, shared) = builder.flow.0.finish();
@@ -314,7 +314,7 @@ impl<'a, 'v, 't> Builder<'a, 'v, 't> {
     ) -> SourceResult<()> {
         let stored = self.scratch.styles.alloc(styles);
         let styles = stored.chain(map);
-        self.interrupt_style(&map, None)?;
+        self.interrupt_style(map, None)?;
         self.accept(elem, styles)?;
         self.interrupt_style(map, Some(styles))?;
         Ok(())
@@ -468,9 +468,9 @@ impl<'a> FlowBuilder<'a> {
 
             let above = BlockElem::above_in(styles);
             let below = BlockElem::below_in(styles);
-            self.0.push(above.clone().pack(), styles);
+            self.0.push(above.pack(), styles);
             self.0.push(content.clone(), styles);
-            self.0.push(below.clone().pack(), styles);
+            self.0.push(below.pack(), styles);
             return true;
         }
 

library/src/layout/par.rs

@@ -365,12 +365,13 @@ impl<'a> Item<'a> {
 }
 
 /// Maps byte offsets back to spans.
+#[derive(Default)]
 pub struct SpanMapper(Vec<(usize, Span)>);
 
 impl SpanMapper {
     /// Create a new span mapper.
     pub fn new() -> Self {
-        Self(vec![])
+        Self::default()
     }
 
     /// Push a span for a segment with the given length.
@@ -745,8 +746,8 @@ fn is_compatible(a: Script, b: Script) -> bool {
 
 /// Get a style property, but only if it is the same for all children of the
 /// paragraph.
-fn shared_get<'a, T: PartialEq>(
+fn shared_get<T: PartialEq>(
-    styles: StyleChain<'a>,
+    styles: StyleChain<'_>,
     children: &[Content],
     getter: fn(StyleChain) -> T,
 ) -> Option<T> {
@@ -754,7 +755,7 @@ fn shared_get<'a, T: PartialEq>(
     children
         .iter()
         .filter_map(|child| child.to_styled())
-        .all(|(_, local)| getter(styles.chain(&local)) == value)
+        .all(|(_, local)| getter(styles.chain(local)) == value)
         .then(|| value)
 }
 

library/src/layout/stack.rs

@@ -198,7 +198,7 @@ impl<'a> StackLayouter<'a> {
         let aligns = if let Some(align) = block.to::<AlignElem>() {
             align.alignment(styles)
         } else if let Some((_, local)) = block.to_styled() {
-            AlignElem::alignment_in(styles.chain(&local))
+            AlignElem::alignment_in(styles.chain(local))
         } else {
             AlignElem::alignment_in(styles)
         }

library/src/math/ctx.rs

@@ -61,7 +61,7 @@ impl<'a, 'b, 'v> MathContext<'a, 'b, 'v> {
         Self {
             vt,
             regions: Regions::one(regions.base(), Axes::splat(false)),
-            font: &font,
+            font,
             ttf: font.ttf(),
             table,
             constants,
@@ -120,7 +120,7 @@ impl<'a, 'b, 'v> MathContext<'a, 'b, 'v> {
 
     pub fn layout_content(&mut self, content: &Content) -> SourceResult<Frame> {
         Ok(content
-            .layout(&mut self.vt, self.outer.chain(&self.local), self.regions)?
+            .layout(self.vt, self.outer.chain(&self.local), self.regions)?
             .into_frame())
     }
 

library/src/math/mod.rs

@@ -297,7 +297,7 @@ impl LayoutMath for Content {
         }
 
         if let Some((elem, styles)) = self.to_styled() {
-            if TextElem::font_in(ctx.styles().chain(&styles))
+            if TextElem::font_in(ctx.styles().chain(styles))
                 != TextElem::font_in(ctx.styles())
             {
                 let frame = ctx.layout_content(self)?;

library/src/meta/bibliography.rs

@@ -52,7 +52,7 @@ pub struct BibliographyElem {
             args.expect::<Spanned<BibPaths>>("path to bibliography file")?;
         for path in &mut paths.0 {
             // resolve paths
-            *path = vm.locate(&path).at(span)?.to_string_lossy().into();
+            *path = vm.locate(path).at(span)?.to_string_lossy().into();
         }
         // check that parsing works
         let _ = load(vm.world(), &paths).at(span)?;
@@ -145,7 +145,7 @@ impl Show for BibliographyElem {
 
         let mut seq = vec![];
         if let Some(title) = self.title(styles) {
-            let title = title.clone().unwrap_or_else(|| {
+            let title = title.unwrap_or_else(|| {
                 TextElem::packed(self.local_name(TextElem::lang_in(styles)))
                     .spanned(self.span())
             });
@@ -526,7 +526,7 @@ fn create(
             // Make link from citation to here work.
             let backlink = {
                 let mut content = Content::empty();
-                content.set_location(ref_location(&reference.entry));
+                content.set_location(ref_location(reference.entry));
                 MetaElem::set_data(vec![Meta::Elem(content)])
             };
 

library/src/meta/outline.rs

@@ -73,7 +73,7 @@ impl Show for OutlineElem {
     fn show(&self, vt: &mut Vt, styles: StyleChain) -> SourceResult<Content> {
         let mut seq = vec![ParbreakElem::new().pack()];
         if let Some(title) = self.title(styles) {
-            let title = title.clone().unwrap_or_else(|| {
+            let title = title.unwrap_or_else(|| {
                 TextElem::packed(self.local_name(TextElem::lang_in(styles)))
                     .spanned(self.span())
             });

library/src/meta/reference.rs

@@ -119,7 +119,7 @@ impl Show for RefElem {
                 .map(TextElem::packed)
                 .unwrap_or_default(),
             Smart::Custom(None) => Content::empty(),
-            Smart::Custom(Some(Supplement::Content(content))) => content.clone(),
+            Smart::Custom(Some(Supplement::Content(content))) => content,
             Smart::Custom(Some(Supplement::Func(func))) => {
                 func.call_vt(vt, [elem.clone().into()])?.display()
             }

library/src/symbols/emoji.rs

@@ -10,7 +10,7 @@ pub fn emoji() -> Module {
 }
 
 /// A list of named emoji.
-const EMOJI: &[(&'static str, Symbol)] = symbols! {
+const EMOJI: &[(&str, Symbol)] = symbols! {
     abacus: '🧮',
     abc: '🔤',
     abcd: '🔡',

library/src/symbols/sym.rs

@@ -10,7 +10,7 @@ pub fn sym() -> Module {
 }
 
 /// The list of general symbols.
-pub(crate) const SYM: &[(&'static str, Symbol)] = symbols! {
+pub(crate) const SYM: &[(&str, Symbol)] = symbols! {
     // Control.
     wj: '\u{2060}',
     zwj: '\u{200D}',

library/src/text/shaping.rs

@@ -384,7 +384,7 @@ pub fn shape<'a>(
 }
 
 /// Shape text with font fallback using the `families` iterator.
-fn shape_segment<'a>(
+fn shape_segment(
     ctx: &mut ShapingContext,
     base: usize,
     text: &str,

library/src/text/shift.rs

@@ -135,7 +135,7 @@ fn search_text(content: &Content, sub: bool) -> Option<EcoString> {
     } else if let Some(children) = content.to_sequence() {
         let mut full = EcoString::new();
         for item in children {
-            match search_text(&item, sub) {
+            match search_text(item, sub) {
                 Some(text) => full.push_str(&text),
                 None => return None,
             }

library/src/visualize/polygon.rs

@@ -62,7 +62,7 @@ impl Layout for PolygonElem {
         let mut frame = Frame::new(target);
 
         // Only create a path if there are more than zero points.
-        if points.len() > 0 {
+        if !points.is_empty() {
             let fill = self.fill(styles);
             let stroke = self.stroke(styles).map(PartialStroke::unwrap_or_default);