More type safety for spans

Cargo.lock

@@ -2990,6 +2990,7 @@ version = "0.7.0"
 dependencies = [
  "clap",
  "comemo",
+ "ecow",
  "iai",
  "once_cell",
  "oxipng",

crates/typst-cli/src/compile.rs

@@ -8,8 +8,8 @@ use typst::diag::{bail, Severity, SourceDiagnostic, StrResult};
 use typst::doc::Document;
 use typst::eval::{eco_format, Tracer};
 use typst::geom::Color;
-use typst::syntax::{FileId, Source};
+use typst::syntax::{FileId, Source, Span};
-use typst::World;
+use typst::{World, WorldExt};
 
 use crate::args::{CompileCommand, DiagnosticFormat, OutputFormat};
 use crate::watch::Status;
@@ -231,19 +231,16 @@ pub fn print_diagnostics(
                 .map(|e| (eco_format!("hint: {e}")).into())
                 .collect(),
         )
-        .with_labels(vec![Label::primary(
+        .with_labels(label(world, diagnostic.span).into_iter().collect());
-            diagnostic.span.id(),
-            world.range(diagnostic.span),
-        )]);
 
         term::emit(&mut w, &config, world, &diag)?;
 
         // Stacktrace-like helper diagnostics.
         for point in &diagnostic.trace {
             let message = point.v.to_string();
-            let help = Diagnostic::help().with_message(message).with_labels(vec![
+            let help = Diagnostic::help()
-                Label::primary(point.span.id(), world.range(point.span)),
+                .with_message(message)
-            ]);
+                .with_labels(label(world, point.span).into_iter().collect());
 
             term::emit(&mut w, &config, world, &help)?;
         }
@@ -252,6 +249,11 @@ pub fn print_diagnostics(
     Ok(())
 }
 
+/// Create a label for a span.
+fn label(world: &SystemWorld, span: Span) -> Option<Label<FileId>> {
+    Some(Label::primary(span.id()?, world.range(span)?))
+}
+
 impl<'a> codespan_reporting::files::Files<'a> for SystemWorld {
     type FileId = FileId;
     type Name = String;

crates/typst-library/src/compute/construct.rs

@@ -935,7 +935,7 @@ pub fn plugin(
     vm: &mut Vm,
 ) -> SourceResult<Plugin> {
     let Spanned { v: path, span } = path;
-    let id = vm.location().join(&path).at(span)?;
+    let id = vm.resolve_path(&path).at(span)?;
     let data = vm.world().file(id).at(span)?;
     Plugin::new(data).at(span)
 }

crates/typst-library/src/compute/data.rs

@@ -37,7 +37,7 @@ pub fn read(
     vm: &mut Vm,
 ) -> SourceResult<Readable> {
     let Spanned { v: path, span } = path;
-    let id = vm.location().join(&path).at(span)?;
+    let id = vm.resolve_path(&path).at(span)?;
     let data = vm.world().file(id).at(span)?;
     Ok(match encoding {
         None => Readable::Bytes(data),
@@ -130,7 +130,7 @@ pub fn csv(
     vm: &mut Vm,
 ) -> SourceResult<Array> {
     let Spanned { v: path, span } = path;
-    let id = vm.location().join(&path).at(span)?;
+    let id = vm.resolve_path(&path).at(span)?;
     let data = vm.world().file(id).at(span)?;
     csv_decode(Spanned::new(Readable::Bytes(data), span), delimiter)
 }
@@ -262,7 +262,7 @@ pub fn json(
     vm: &mut Vm,
 ) -> SourceResult<Value> {
     let Spanned { v: path, span } = path;
-    let id = vm.location().join(&path).at(span)?;
+    let id = vm.resolve_path(&path).at(span)?;
     let data = vm.world().file(id).at(span)?;
     json_decode(Spanned::new(Readable::Bytes(data), span))
 }
@@ -350,7 +350,7 @@ pub fn toml(
     vm: &mut Vm,
 ) -> SourceResult<Value> {
     let Spanned { v: path, span } = path;
-    let id = vm.location().join(&path).at(span)?;
+    let id = vm.resolve_path(&path).at(span)?;
     let data = vm.world().file(id).at(span)?;
 
     toml_decode(Spanned::new(Readable::Bytes(data), span))
@@ -462,7 +462,7 @@ pub fn yaml(
     vm: &mut Vm,
 ) -> SourceResult<Value> {
     let Spanned { v: path, span } = path;
-    let id = vm.location().join(&path).at(span)?;
+    let id = vm.resolve_path(&path).at(span)?;
     let data = vm.world().file(id).at(span)?;
     yaml_decode(Spanned::new(Readable::Bytes(data), span))
 }
@@ -568,7 +568,7 @@ pub fn xml(
     vm: &mut Vm,
 ) -> SourceResult<Value> {
     let Spanned { v: path, span } = path;
-    let id = vm.location().join(&path).at(span)?;
+    let id = vm.resolve_path(&path).at(span)?;
     let data = vm.world().file(id).at(span)?;
     xml_decode(Spanned::new(Readable::Bytes(data), span))
 }

crates/typst-library/src/meta/bibliography.rs

@@ -58,7 +58,7 @@ pub struct BibliographyElem {
         let data = paths.0
             .iter()
             .map(|path| {
-                let id = vm.location().join(path).at(span)?;
+                let id = vm.resolve_path(path).at(span)?;
                 vm.world().file(id).at(span)
             })
             .collect::<SourceResult<Vec<Bytes>>>()?;

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

@@ -490,7 +490,7 @@ fn parse_syntaxes(
         .0
         .iter()
         .map(|path| {
-            let id = vm.location().join(path).at(span)?;
+            let id = vm.resolve_path(path).at(span)?;
             vm.world().file(id).at(span)
         })
         .collect::<SourceResult<Vec<Bytes>>>()?;
@@ -522,7 +522,7 @@ fn parse_theme(
     };
 
     // Load theme file.
-    let id = vm.location().join(&path).at(span)?;
+    let id = vm.resolve_path(&path).at(span)?;
     let data = vm.world().file(id).at(span)?;
 
     // Check that parsing works.

crates/typst-library/src/visualize/image.rs

@@ -44,7 +44,7 @@ pub struct ImageElem {
     #[parse(
         let Spanned { v: path, span } =
             args.expect::<Spanned<EcoString>>("path to image file")?;
-        let id = vm.location().join(&path).at(span)?;
+        let id = vm.resolve_path(&path).at(span)?;
         let data = vm.world().file(id).at(span)?;
         path
     )]

crates/typst-syntax/src/file.rs

@@ -16,9 +16,6 @@ use super::is_ident;
 static INTERNER: Lazy<RwLock<Interner>> =
     Lazy::new(|| RwLock::new(Interner { to_id: HashMap::new(), from_id: Vec::new() }));
 
-/// The path that we use for detached file ids.
-static DETACHED_PATH: Lazy<VirtualPath> = Lazy::new(|| VirtualPath::new("/unknown"));
-
 /// A package-path interner.
 struct Interner {
     to_id: HashMap<Pair, FileId>,
@@ -48,66 +45,41 @@ impl FileId {
         }
 
         let mut interner = INTERNER.write().unwrap();
-        let len = interner.from_id.len();
+        let num = interner.from_id.len().try_into().expect("out of file ids");
-        if len >= usize::from(u16::MAX) {
-            panic!("too many file specifications");
-        }
 
         // Create a new entry forever by leaking the pair. We can't leak more
         // than 2^16 pair (and typically will leak a lot less), so its not a
         // big deal.
-        let id = FileId(len as u16);
+        let id = FileId(num);
         let leaked = Box::leak(Box::new(pair));
         interner.to_id.insert(leaked, id);
         interner.from_id.push(leaked);
         id
     }
 
-    /// Get an id that does not identify any real file.
-    pub const fn detached() -> Self {
-        Self(u16::MAX)
-    }
-
-    /// Whether the id is the detached.
-    pub const fn is_detached(self) -> bool {
-        self.0 == Self::detached().0
-    }
-
     /// The package the file resides in, if any.
     pub fn package(&self) -> Option<&'static PackageSpec> {
-        if self.is_detached() {
+        self.pair().0.as_ref()
-            None
-        } else {
-            self.pair().0.as_ref()
-        }
     }
 
     /// The absolute and normalized path to the file _within_ the project or
     /// package.
     pub fn vpath(&self) -> &'static VirtualPath {
-        if self.is_detached() {
+        &self.pair().1
-            &DETACHED_PATH
-        } else {
-            &self.pair().1
-        }
     }
 
     /// Resolve a file location relative to this file.
-    pub fn join(self, path: &str) -> Result<Self, EcoString> {
+    pub fn join(self, path: &str) -> Self {
-        if self.is_detached() {
+        Self::new(self.package().cloned(), self.vpath().join(path))
-            Err("cannot access file system from here")?;
-        }
-
-        Ok(Self::new(self.package().cloned(), self.vpath().join(path)))
     }
 
     /// Construct from a raw number.
-    pub(crate) const fn from_u16(v: u16) -> Self {
+    pub(crate) const fn from_raw(v: u16) -> Self {
         Self(v)
     }
 
     /// Extract the raw underlying number.
-    pub(crate) const fn as_u16(self) -> u16 {
+    pub(crate) const fn into_raw(self) -> u16 {
         self.0
     }
 

crates/typst-syntax/src/node.rs

@@ -202,7 +202,7 @@ impl SyntaxNode {
             return Err(Unnumberable);
         }
 
-        let mid = Span::new(id, (within.start + within.end) / 2);
+        let mid = Span::new(id, (within.start + within.end) / 2).unwrap();
         match &mut self.0 {
             Repr::Leaf(leaf) => leaf.span = mid,
             Repr::Inner(inner) => Arc::make_mut(inner).numberize(id, None, within)?,
@@ -424,7 +424,7 @@ impl InnerNode {
         let mut start = within.start;
         if range.is_none() {
             let end = start + stride;
-            self.span = Span::new(id, (start + end) / 2);
+            self.span = Span::new(id, (start + end) / 2).unwrap();
             self.upper = within.end;
             start = end;
         }
@@ -448,6 +448,7 @@ impl InnerNode {
         mut range: Range<usize>,
         replacement: Vec<SyntaxNode>,
     ) -> NumberingResult {
+        let Some(id) = self.span.id() else { return Err(Unnumberable) };
         let superseded = &self.children[range.clone()];
 
         // Compute the new byte length.
@@ -505,7 +506,6 @@ impl InnerNode {
 
             // Try to renumber.
             let within = start_number..end_number;
-            let id = self.span.id();
             if self.numberize(id, Some(renumber), within).is_ok() {
                 return Ok(());
             }

crates/typst-syntax/src/reparser.rs

@@ -21,7 +21,9 @@ pub fn reparse(
     try_reparse(text, replaced, replacement_len, None, root, 0).unwrap_or_else(|| {
         let id = root.span().id();
         *root = parse(text);
-        root.numberize(id, Span::FULL).unwrap();
+        if let Some(id) = id {
+            root.numberize(id, Span::FULL).unwrap();
+        }
         0..text.len()
     })
 }

crates/typst-syntax/src/source.rs

@@ -9,6 +9,7 @@ use comemo::Prehashed;
 
 use super::reparser::reparse;
 use super::{is_newline, parse, FileId, LinkedNode, Span, SyntaxNode};
+use crate::VirtualPath;
 
 /// A source file.
 ///
@@ -44,19 +45,7 @@ impl Source {
 
     /// Create a source file without a real id and path, usually for testing.
     pub fn detached(text: impl Into<String>) -> Self {
-        Self::new(FileId::detached(), text.into())
+        Self::new(FileId::new(None, VirtualPath::new("main.typ")), text.into())
-    }
-
-    /// Create a source file with the same synthetic span for all nodes.
-    pub fn synthesized(text: String, span: Span) -> Self {
-        let mut root = parse(&text);
-        root.synthesize(span);
-        Self(Arc::new(Repr {
-            id: FileId::detached(),
-            lines: lines(&text),
-            text: Prehashed::new(text),
-            root: Prehashed::new(root),
-        }))
     }
 
     /// The root node of the file's untyped syntax tree.
@@ -151,12 +140,9 @@ impl Source {
 
     /// Get the byte range for the given span in this file.
     ///
-    /// Panics if the span does not point into this source file.
+    /// Returns `None` if the span does not point into this source file.
-    #[track_caller]
+    pub fn range(&self, span: Span) -> Option<Range<usize>> {
-    pub fn range(&self, span: Span) -> Range<usize> {
+        Some(self.find(span)?.range())
-        self.find(span)
-            .expect("span does not point into this source file")
-            .range()
     }
 
     /// Return the index of the UTF-16 code unit at the byte index.

crates/typst-syntax/src/span.rs

@@ -28,54 +28,57 @@ pub struct Span(NonZeroU64);
 
 impl Span {
     /// The full range of numbers available for span numbering.
-    pub const FULL: Range<u64> = 2..(1 << Self::BITS);
+    pub(super) const FULL: Range<u64> = 2..(1 << Self::BITS);
+
+    /// The value reserved for the detached span.
     const DETACHED: u64 = 1;
 
-    // Data layout:
+    /// Data layout:
-    // | 16 bits source id | 48 bits number |
+    /// | 16 bits source id | 48 bits number |
     const BITS: usize = 48;
 
     /// Create a new span from a source id and a unique number.
     ///
-    /// Panics if the `number` is not contained in `FULL`.
+    /// Returns `None` if `number` is not contained in `FULL`.
-    #[track_caller]
+    pub(super) const fn new(id: FileId, number: u64) -> Option<Self> {
-    pub const fn new(id: FileId, number: u64) -> Self {
+        if number < Self::FULL.start || number >= Self::FULL.end {
-        assert!(
+            return None;
-            Self::FULL.start <= number && number < Self::FULL.end,
+        }
-            "span number outside valid range"
-        );
 
-        Self::pack(id, number)
+        let bits = ((id.into_raw() as u64) << Self::BITS) | number;
-    }
-
-    /// A span that does not point into any source file.
-    pub const fn detached() -> Self {
-        Self::pack(FileId::detached(), Self::DETACHED)
-    }
-
-    /// Pack the components into a span.
-    #[track_caller]
-    const fn pack(id: FileId, number: u64) -> Span {
-        let bits = ((id.as_u16() as u64) << Self::BITS) | number;
         match NonZeroU64::new(bits) {
-            Some(v) => Self(v),
+            Some(v) => Some(Self(v)),
-            None => panic!("span encoding is zero"),
+            None => unreachable!(),
         }
     }
 
-    /// The id of the source file the span points into.
+    /// Create a span that does not point into any source file.
-    pub const fn id(self) -> FileId {
+    pub const fn detached() -> Self {
-        FileId::from_u16((self.0.get() >> Self::BITS) as u16)
+        match NonZeroU64::new(Self::DETACHED) {
-    }
+            Some(v) => Self(v),
-
+            None => unreachable!(),
-    /// The unique number of the span within its source file.
+        }
-    pub const fn number(self) -> u64 {
-        self.0.get() & ((1 << Self::BITS) - 1)
     }
 
     /// Whether the span is detached.
     pub const fn is_detached(self) -> bool {
-        self.id().is_detached()
+        self.0.get() == Self::DETACHED
+    }
+
+    /// The id of the source file the span points into.
+    ///
+    /// Returns `None` if the span is detached.
+    pub const fn id(self) -> Option<FileId> {
+        if self.is_detached() {
+            return None;
+        }
+        let bits = (self.0.get() >> Self::BITS) as u16;
+        Some(FileId::from_raw(bits))
+    }
+
+    /// The unique number of the span within its [`Source`](super::Source).
+    pub const fn number(self) -> u64 {
+        self.0.get() & ((1 << Self::BITS) - 1)
     }
 }
 
@@ -120,9 +123,9 @@ mod tests {
 
     #[test]
     fn test_span_encoding() {
-        let id = FileId::from_u16(5);
+        let id = FileId::from_raw(5);
-        let span = Span::new(id, 10);
+        let span = Span::new(id, 10).unwrap();
-        assert_eq!(span.id(), id);
+        assert_eq!(span.id(), Some(id));
         assert_eq!(span.number(), 10);
     }
 }

crates/typst/src/diag.rs

@@ -9,7 +9,7 @@ use std::string::FromUtf8Error;
 use comemo::Tracked;
 
 use crate::syntax::{PackageSpec, Span, Spanned, SyntaxError};
-use crate::World;
+use crate::{World, WorldExt};
 
 /// Early-return with a [`StrResult`] or [`SourceResult`].
 ///
@@ -206,16 +206,12 @@ impl<T> Trace<T> for SourceResult<T> {
         F: Fn() -> Tracepoint,
     {
         self.map_err(|mut errors| {
-            if span.is_detached() {
+            let Some(trace_range) = world.range(span) else { return errors };
-                return errors;
+            for error in errors.iter_mut() {
-            }
-
-            let trace_range = world.range(span);
-            for error in errors.iter_mut().filter(|e| !e.span.is_detached()) {
                 // Skip traces that surround the error.
-                if error.span.id() == span.id() {
+                if let Some(error_range) = world.range(error.span) {
-                    let error_range = world.range(error.span);
+                    if error.span.id() == span.id()
-                    if trace_range.start <= error_range.start
+                        && trace_range.start <= error_range.start
                         && trace_range.end >= error_range.end
                     {
                         continue;

crates/typst/src/eval/func.rs

@@ -94,9 +94,8 @@ impl Func {
             }
             Repr::Closure(closure) => {
                 // Determine the route inside the closure.
-                let fresh = Route::new(closure.location);
+                let fresh = Route::new(closure.file);
-                let route =
+                let route = if vm.file.is_none() { fresh.track() } else { vm.route };
-                    if vm.location.is_detached() { fresh.track() } else { vm.route };
 
                 Closure::call(
                     self,
@@ -134,7 +133,7 @@ impl Func {
             delayed: TrackedMut::reborrow_mut(&mut vt.delayed),
             tracer: TrackedMut::reborrow_mut(&mut vt.tracer),
         };
-        let mut vm = Vm::new(vt, route.track(), FileId::detached(), scopes);
+        let mut vm = Vm::new(vt, route.track(), None, scopes);
         let args = Args::new(self.span(), args);
         self.call_vm(&mut vm, args)
     }
@@ -298,7 +297,7 @@ pub(super) struct Closure {
     /// The closure's syntax node. Must be castable to `ast::Closure`.
     pub node: SyntaxNode,
     /// The source file where the closure was defined.
-    pub location: FileId,
+    pub file: Option<FileId>,
     /// Default values of named parameters.
     pub defaults: Vec<Value>,
     /// Captured values from outer scopes.
@@ -351,7 +350,7 @@ impl Closure {
         };
 
         // Prepare VM.
-        let mut vm = Vm::new(vt, route, this.location, scopes);
+        let mut vm = Vm::new(vt, route, this.file, scopes);
         vm.depth = depth;
 
         // Provide the closure itself for recursive calls.

crates/typst/src/eval/mod.rs

@@ -122,7 +122,7 @@ pub fn eval(
     // Prepare VM.
     let route = Route::insert(route, id);
     let scopes = Scopes::new(Some(library));
-    let mut vm = Vm::new(vt, route.track(), id, scopes);
+    let mut vm = Vm::new(vt, route.track(), Some(id), scopes);
 
     let root = source.root();
     let errors = root.errors();
@@ -189,9 +189,8 @@ pub fn eval_string(
 
     // Prepare VM.
     let route = Route::default();
-    let id = FileId::detached();
     let scopes = Scopes::new(Some(world.library()));
-    let mut vm = Vm::new(vt, route.track(), id, scopes);
+    let mut vm = Vm::new(vt, route.track(), None, scopes);
     vm.scopes.scopes.push(scope);
 
     // Evaluate the code.
@@ -235,8 +234,8 @@ pub struct Vm<'a> {
     items: LangItems,
     /// The route of source ids the VM took to reach its current location.
     route: Tracked<'a, Route<'a>>,
-    /// The current location.
+    /// The id of the currently evaluated file.
-    location: FileId,
+    file: Option<FileId>,
     /// A control flow event that is currently happening.
     flow: Option<FlowEvent>,
     /// The stack of scopes.
@@ -252,16 +251,16 @@ impl<'a> Vm<'a> {
     fn new(
         vt: Vt<'a>,
         route: Tracked<'a, Route>,
-        location: FileId,
+        file: Option<FileId>,
         scopes: Scopes<'a>,
     ) -> Self {
-        let traced = vt.tracer.span(location);
+        let traced = file.and_then(|id| vt.tracer.span(id));
         let items = vt.world.library().items.clone();
         Self {
             vt,
             items,
             route,
-            location,
+            file,
             flow: None,
             scopes,
             depth: 0,
@@ -274,9 +273,21 @@ impl<'a> Vm<'a> {
         self.vt.world
     }
 
-    /// The location to which paths are relative currently.
+    /// The id of the currently evaluated file.
-    pub fn location(&self) -> FileId {
+    ///
-        self.location
+    /// Returns `None` if the VM is in a detached context, e.g. when evaluating
+    /// a user-provided string.
+    pub fn file(&self) -> Option<FileId> {
+        self.file
+    }
+
+    /// Resolve a path relative to the currently evaluated file.
+    pub fn resolve_path(&self, path: &str) -> StrResult<FileId> {
+        let Some(file) = self.file else {
+            bail!("cannot access file system from here");
+        };
+
+        Ok(file.join(path))
     }
 
     /// Define a variable in the current scope.
@@ -331,8 +342,8 @@ pub struct Route<'a> {
 
 impl<'a> Route<'a> {
     /// Create a new route with just one entry.
-    pub fn new(id: FileId) -> Self {
+    pub fn new(id: Option<FileId>) -> Self {
-        Self { id: Some(id), outer: None }
+        Self { id, outer: None }
     }
 
     /// Insert a new id into the route.
@@ -1301,7 +1312,7 @@ impl Eval for ast::Closure<'_> {
         // Define the closure.
         let closure = Closure {
             node: self.to_untyped().clone(),
-            location: vm.location,
+            file: vm.file,
             defaults,
             captured,
         };
@@ -1809,7 +1820,7 @@ fn import_package(vm: &mut Vm, spec: PackageSpec, span: Span) -> SourceResult<Mo
     manifest.validate(&spec).at(span)?;
 
     // Evaluate the entry point.
-    let entrypoint_id = manifest_id.join(&manifest.package.entrypoint).at(span)?;
+    let entrypoint_id = manifest_id.join(&manifest.package.entrypoint);
     let source = vm.world().source(entrypoint_id).at(span)?;
     let point = || Tracepoint::Import;
     Ok(eval(vm.world(), vm.route, TrackedMut::reborrow_mut(&mut vm.vt.tracer), &source)
@@ -1821,7 +1832,7 @@ fn import_package(vm: &mut Vm, spec: PackageSpec, span: Span) -> SourceResult<Mo
 fn import_file(vm: &mut Vm, path: &str, span: Span) -> SourceResult<Module> {
     // Load the source file.
     let world = vm.world();
-    let id = vm.location().join(path).at(span)?;
+    let id = vm.resolve_path(path).at(span)?;
     let source = world.source(id).at(span)?;
 
     // Prevent cyclic importing.

crates/typst/src/eval/tracer.rs

@@ -45,7 +45,7 @@ impl Tracer {
 impl Tracer {
     /// The traced span if it is part of the given source file.
     pub fn span(&self, id: FileId) -> Option<Span> {
-        if self.span.map(Span::id) == Some(id) {
+        if self.span.and_then(Span::id) == Some(id) {
             self.span
         } else {
             None

crates/typst/src/ide/analyze.rs

@@ -46,7 +46,7 @@ pub fn analyze_expr(world: &dyn World, node: &LinkedNode) -> EcoVec<Value> {
 pub fn analyze_import(world: &dyn World, source: &Source, path: &str) -> Option<Module> {
     let route = Route::default();
     let mut tracer = Tracer::default();
-    let id = source.id().join(path).ok()?;
+    let id = source.id().join(path);
     let source = world.source(id).ok()?;
     eval(world.track(), route.track(), tracer.track_mut(), &source).ok()
 }

crates/typst/src/ide/highlight.rs

@@ -379,7 +379,7 @@ mod tests {
     use std::ops::Range;
 
     use super::*;
-    use crate::syntax::Source;
+    use crate::syntax::parse;
 
     #[test]
     fn test_highlighting() {
@@ -388,8 +388,8 @@ mod tests {
         #[track_caller]
         fn test(text: &str, goal: &[(Range<usize>, Tag)]) {
             let mut vec = vec![];
-            let source = Source::detached(text);
+            let root = parse(text);
-            highlight_tree(&mut vec, &LinkedNode::new(source.root()));
+            highlight_tree(&mut vec, &LinkedNode::new(&root));
             assert_eq!(vec, goal);
         }
 

crates/typst/src/ide/jump.rs

@@ -21,9 +21,10 @@ pub enum Jump {
 
 impl Jump {
     fn from_span(world: &dyn World, span: Span) -> Option<Self> {
-        let source = world.source(span.id()).ok()?;
+        let id = span.id()?;
+        let source = world.source(id).ok()?;
         let node = source.find(span)?;
-        Some(Self::Source(span.id(), node.offset()))
+        Some(Self::Source(id, node.offset()))
     }
 }
 
@@ -67,18 +68,15 @@ pub fn jump_from_click(
 
             FrameItem::Text(text) => {
                 for glyph in &text.glyphs {
-                    let (span, span_offset) = glyph.span;
-                    if span.is_detached() {
-                        continue;
-                    }
-
                     let width = glyph.x_advance.at(text.size);
                     if is_in_rect(
                         Point::new(pos.x, pos.y - text.size),
                         Size::new(width, text.size),
                         click,
                     ) {
-                        let source = world.source(span.id()).ok()?;
+                        let (span, span_offset) = glyph.span;
+                        let Some(id) = span.id() else { continue };
+                        let source = world.source(id).ok()?;
                         let node = source.find(span)?;
                         let pos = if node.kind() == SyntaxKind::Text {
                             let range = node.range();

crates/typst/src/lib.rs

@@ -142,12 +142,18 @@ pub trait World {
     fn packages(&self) -> &[(PackageSpec, Option<EcoString>)] {
         &[]
     }
+}
 
+/// Helper methods on [`World`] implementations.
+pub trait WorldExt {
     /// Get the byte range for a span.
-    #[track_caller]
+    ///
-    fn range(&self, span: Span) -> Range<usize> {
+    /// Returns `None` if the `Span` does not point into any source file.
-        self.source(span.id())
+    fn range(&self, span: Span) -> Option<Range<usize>>;
-            .expect("span does not point into any source file")
+}
-            .range(span)
+
+impl<T: World> WorldExt for T {
+    fn range(&self, span: Span) -> Option<Range<usize>> {
+        self.source(span.id()?).ok()?.range(span)
     }
 }

crates/typst/src/model/mod.rs

@@ -31,6 +31,7 @@ use comemo::{Track, Tracked, TrackedMut, Validate};
 use crate::diag::{warning, SourceDiagnostic, SourceResult};
 use crate::doc::Document;
 use crate::eval::Tracer;
+use crate::syntax::Span;
 use crate::World;
 
 /// Typeset content into a fully layouted document.
@@ -88,11 +89,8 @@ pub fn typeset(
 
         if iter >= 5 {
             tracer.warn(
-                warning!(
+                warning!(Span::detached(), "layout did not converge within 5 attempts",)
-                    world.main().root().span(),
+                    .with_hint("check if any states or queries are updating themselves"),
-                    "layout did not converge within 5 attempts",
-                )
-                .with_hint("check if any states or queries are updating themselves"),
             );
             break;
         }

tests/Cargo.toml

@@ -10,6 +10,7 @@ publish = false
 typst = { path = "../crates/typst" }
 typst-library = { path = "../crates/typst-library" }
 comemo = "0.3"
+ecow = { version = "0.1.1", features = ["serde"] }
 iai = { git = "https://github.com/reknih/iai" }
 once_cell = "1"
 oxipng = { version = "8.0.0", default-features = false, features = ["filetime", "parallel", "zopfli"] }

tests/src/tests.rs

@@ -4,15 +4,15 @@ use std::cell::{RefCell, RefMut};
 use std::collections::{HashMap, HashSet};
 use std::env;
 use std::ffi::OsStr;
-use std::fmt::Write as FmtWrite;
+use std::fmt::{self, Display, Formatter, Write as _};
 use std::fs;
 use std::io::{self, Write};
-use std::iter;
 use std::ops::Range;
 use std::path::{Path, PathBuf};
 
 use clap::Parser;
 use comemo::{Prehashed, Track};
+use ecow::EcoString;
 use oxipng::{InFile, Options, OutFile};
 use rayon::iter::{ParallelBridge, ParallelIterator};
 use std::cell::OnceCell;
@@ -26,7 +26,7 @@ use typst::eval::{eco_format, func, Bytes, Datetime, Library, NoneValue, Tracer,
 use typst::font::{Font, FontBook};
 use typst::geom::{Abs, Color, RgbaColor, Smart};
 use typst::syntax::{FileId, Source, Span, SyntaxNode, VirtualPath};
-use typst::World;
+use typst::{World, WorldExt};
 use typst_library::layout::{Margin, PageElem};
 use typst_library::text::{TextElem, TextSize};
 
@@ -237,7 +237,7 @@ impl TestWorld {
 
         Self {
             print,
-            main: FileId::detached(),
+            main: FileId::new(None, VirtualPath::new("main.typ")),
             library: Prehashed::new(library()),
             book: Prehashed::new(FontBook::from_fonts(&fonts)),
             fonts,
@@ -555,39 +555,46 @@ fn test_part(
     // This has one caveat: due to the format of the expected hints, we can not
     // verify if a hint belongs to a diagnostic or not. That should be irrelevant
     // however, as the line of the hint is still verified.
-    let actual_diagnostics: HashSet<UserOutput> = diagnostics
+    let mut actual_diagnostics = HashSet::new();
-        .into_iter()
+    for diagnostic in &diagnostics {
-        .inspect(|diagnostic| assert!(!diagnostic.span.is_detached()))
+        // Ignore diagnostics from other files.
-        .filter(|diagnostic| diagnostic.span.id() == source.id())
+        if diagnostic.span.id().map_or(false, |id| id != source.id()) {
-        .flat_map(|diagnostic| {
+            continue;
-            let range = world.range(diagnostic.span);
+        }
-            let message = diagnostic.message.replace('\\', "/");
-            let output = match diagnostic.severity {
-                Severity::Error => UserOutput::Error(range.clone(), message),
-                Severity::Warning => UserOutput::Warning(range.clone(), message),
-            };
 
-            let hints = diagnostic
+        let annotation = Annotation {
-                .hints
+            kind: match diagnostic.severity {
-                .iter()
+                Severity::Error => AnnotationKind::Error,
-                .filter(|_| validate_hints) // No unexpected hints should be verified if disabled.
+                Severity::Warning => AnnotationKind::Warning,
-                .map(|hint| UserOutput::Hint(range.clone(), hint.to_string()));
+            },
+            range: world.range(diagnostic.span),
+            message: diagnostic.message.replace('\\', "/").into(),
+        };
 
-            iter::once(output).chain(hints).collect::<Vec<_>>()
+        if validate_hints {
-        })
+            for hint in &diagnostic.hints {
-        .collect();
+                actual_diagnostics.insert(Annotation {
+                    kind: AnnotationKind::Hint,
+                    message: hint.clone(),
+                    range: annotation.range.clone(),
+                });
+            }
+        }
+
+        actual_diagnostics.insert(annotation);
+    }
 
     // Basically symmetric_difference, but we need to know where an item is coming from.
     let mut unexpected_outputs = actual_diagnostics
-        .difference(&metadata.invariants)
+        .difference(&metadata.annotations)
         .collect::<Vec<_>>();
     let mut missing_outputs = metadata
-        .invariants
+        .annotations
         .difference(&actual_diagnostics)
         .collect::<Vec<_>>();
 
-    unexpected_outputs.sort_by_key(|&o| o.start());
+    unexpected_outputs.sort_by_key(|&v| v.range.as_ref().map(|r| r.start));
-    missing_outputs.sort_by_key(|&o| o.start());
+    missing_outputs.sort_by_key(|&v| v.range.as_ref().map(|r| r.start));
 
     // This prints all unexpected emits first, then all missing emits.
     // Is this reasonable or subject to change?
@@ -597,41 +604,34 @@ fn test_part(
 
         for unexpected in unexpected_outputs {
             write!(output, "    Not annotated | ").unwrap();
-            print_user_output(output, &source, line, unexpected)
+            print_annotation(output, &source, line, unexpected)
         }
 
         for missing in missing_outputs {
             write!(output, "    Not emitted   | ").unwrap();
-            print_user_output(output, &source, line, missing)
+            print_annotation(output, &source, line, missing)
         }
     }
 
     (ok, compare_ref, frames)
 }
 
-fn print_user_output(
+fn print_annotation(
     output: &mut String,
     source: &Source,
     line: usize,
-    user_output: &UserOutput,
+    annotation: &Annotation,
 ) {
-    let (range, message) = match &user_output {
+    let Annotation { range, message, kind } = annotation;
-        UserOutput::Error(r, m) => (r, m),
+    write!(output, "{kind}: ").unwrap();
-        UserOutput::Warning(r, m) => (r, m),
+    if let Some(range) = range {
-        UserOutput::Hint(r, m) => (r, m),
+        let start_line = 1 + line + source.byte_to_line(range.start).unwrap();
-    };
+        let start_col = 1 + source.byte_to_column(range.start).unwrap();
-
+        let end_line = 1 + line + source.byte_to_line(range.end).unwrap();
-    let start_line = 1 + line + source.byte_to_line(range.start).unwrap();
+        let end_col = 1 + source.byte_to_column(range.end).unwrap();
-    let start_col = 1 + source.byte_to_column(range.start).unwrap();
+        write!(output, "{start_line}:{start_col}-{end_line}:{end_col}: ").unwrap();
-    let end_line = 1 + line + source.byte_to_line(range.end).unwrap();
+    }
-    let end_col = 1 + source.byte_to_column(range.end).unwrap();
+    writeln!(output, "{message}").unwrap();
-    let kind = match user_output {
-        UserOutput::Error(_, _) => "Error",
-        UserOutput::Warning(_, _) => "Warning",
-        UserOutput::Hint(_, _) => "Hint",
-    };
-    writeln!(output, "{kind}: {start_line}:{start_col}-{end_line}:{end_col}: {message}")
-        .unwrap();
 }
 
 struct TestConfiguration {
@@ -641,101 +641,93 @@ struct TestConfiguration {
 
 struct TestPartMetadata {
     part_configuration: TestConfiguration,
-    invariants: HashSet<UserOutput>,
+    annotations: HashSet<Annotation>,
 }
 
-#[derive(PartialEq, Eq, Debug, Hash)]
+#[derive(Debug, Clone, Eq, PartialEq, Hash)]
-enum UserOutput {
+struct Annotation {
-    Error(Range<usize>, String),
+    range: Option<Range<usize>>,
-    Warning(Range<usize>, String),
+    message: EcoString,
-    Hint(Range<usize>, String),
+    kind: AnnotationKind,
 }
 
-impl UserOutput {
+#[derive(Debug, Copy, Clone, Eq, PartialEq, Hash)]
-    fn start(&self) -> usize {
+enum AnnotationKind {
+    Error,
+    Warning,
+    Hint,
+}
+
+impl AnnotationKind {
+    fn iter() -> impl Iterator<Item = Self> {
+        [AnnotationKind::Error, AnnotationKind::Warning, AnnotationKind::Hint].into_iter()
+    }
+
+    fn as_str(self) -> &'static str {
         match self {
-            UserOutput::Error(r, _) => r.start,
+            AnnotationKind::Error => "Error",
-            UserOutput::Warning(r, _) => r.start,
+            AnnotationKind::Warning => "Warning",
-            UserOutput::Hint(r, _) => r.start,
+            AnnotationKind::Hint => "Hint",
         }
     }
+}
 
-    fn error(range: Range<usize>, message: String) -> UserOutput {
+impl Display for AnnotationKind {
-        UserOutput::Error(range, message)
+    fn fmt(&self, f: &mut Formatter) -> fmt::Result {
-    }
+        f.pad(self.as_str())
-
-    fn warning(range: Range<usize>, message: String) -> UserOutput {
-        UserOutput::Warning(range, message)
-    }
-
-    fn hint(range: Range<usize>, message: String) -> UserOutput {
-        UserOutput::Hint(range, message)
     }
 }
 
 fn parse_part_metadata(source: &Source) -> TestPartMetadata {
     let mut compare_ref = None;
     let mut validate_hints = None;
-    let mut expectations = HashSet::default();
+    let mut annotations = HashSet::default();
 
     let lines: Vec<_> = source.text().lines().map(str::trim).collect();
     for (i, line) in lines.iter().enumerate() {
         compare_ref = get_flag_metadata(line, "Ref").or(compare_ref);
         validate_hints = get_flag_metadata(line, "Hints").or(validate_hints);
 
-        fn num(s: &mut Scanner) -> isize {
+        fn num(s: &mut Scanner) -> Option<isize> {
             let mut first = true;
             let n = &s.eat_while(|c: char| {
                 let valid = first && c == '-' || c.is_numeric();
                 first = false;
                 valid
             });
-            n.parse().unwrap_or_else(|e| panic!("{n} is not a number ({e})"))
+            n.parse().ok()
         }
 
         let comments_until_code =
             lines[i..].iter().take_while(|line| line.starts_with("//")).count();
 
-        let pos = |s: &mut Scanner| -> usize {
+        let pos = |s: &mut Scanner| -> Option<usize> {
-            let first = num(s) - 1;
+            let first = num(s)? - 1;
             let (delta, column) =
-                if s.eat_if(':') { (first, num(s) - 1) } else { (0, first) };
+                if s.eat_if(':') { (first, num(s)? - 1) } else { (0, first) };
-            let line = (i + comments_until_code)
+            let line = (i + comments_until_code).checked_add_signed(delta)?;
-                .checked_add_signed(delta)
+            source.line_column_to_byte(line, usize::try_from(column).ok()?)
-                .expect("line number overflowed limits");
-            source
-                .line_column_to_byte(
-                    line,
-                    usize::try_from(column).expect("column number overflowed limits"),
-                )
-                .unwrap()
         };
 
-        let error_factory: fn(Range<usize>, String) -> UserOutput = UserOutput::error;
+        let range = |s: &mut Scanner| -> Option<Range<usize>> {
-        let warning_factory: fn(Range<usize>, String) -> UserOutput = UserOutput::warning;
+            let start = pos(s)?;
-        let hint_factory: fn(Range<usize>, String) -> UserOutput = UserOutput::hint;
+            let end = if s.eat_if('-') { pos(s)? } else { start };
+            Some(start..end)
+        };
 
-        let error_metadata = get_metadata(line, "Error").map(|s| (s, error_factory));
+        for kind in AnnotationKind::iter() {
-        let get_warning_metadata =
+            let Some(expectation) = get_metadata(line, kind.as_str()) else { continue };
-            || get_metadata(line, "Warning").map(|s| (s, warning_factory));
-        let get_hint_metadata = || get_metadata(line, "Hint").map(|s| (s, hint_factory));
-
-        if let Some((expectation, factory)) = error_metadata
-            .or_else(get_warning_metadata)
-            .or_else(get_hint_metadata)
-        {
             let mut s = Scanner::new(expectation);
-            let start = pos(&mut s);
+            let range = range(&mut s);
-            let end = if s.eat_if('-') { pos(&mut s) } else { start };
+            let rest = if range.is_some() { s.after() } else { s.string() };
-            let range = start..end;
+            let message = rest.trim().into();
-
+            annotations.insert(Annotation { kind, range, message });
-            expectations.insert(factory(range, s.after().trim().to_string()));
+        }
-        };
     }
 
     TestPartMetadata {
         part_configuration: TestConfiguration { compare_ref, validate_hints },
-        invariants: expectations,
+        annotations,
     }
 }
 

tests/typ/meta/state.typ

@@ -49,10 +49,8 @@ Was: #locate(location => {
 
 ---
 // Make sure that a warning is produced if the layout fails to converge.
-// Warning: -3:1-6:1 layout did not converge within 5 attempts
+// Warning: layout did not converge within 5 attempts
-// Hint: -3:1-6:1 check if any states or queries are updating themselves
+// Hint: check if any states or queries are updating themselves
-#let s = state("x", 1)
+#let s = state("s", 1)
-#locate(loc => {
+#locate(loc => s.update(s.final(loc) + 1))
-  s.update(s.final(loc) + 1)
-})
 #s.display()