use rustc_data_structures::sync::{AtomicU32, Lrc, MappedReadGuard, ReadGuard, RwLock};
use std::cmp;
use std::hash::Hash;
-use std::path::{Path, PathBuf};
+use std::path::{self, Path, PathBuf};
use std::sync::atomic::Ordering;
use std::fs;
/// Finds the width of the character, either before or after the end of provided span,
/// depending on the `forwards` parameter.
+ #[instrument(skip(self, sp))]
fn find_width_of_character_at_span(&self, sp: Span, forwards: bool) -> u32 {
let sp = sp.data();
if sp.lo == sp.hi && !forwards {
- debug!("find_width_of_character_at_span: early return empty span");
+ debug!("early return empty span");
return 1;
}
let local_begin = self.lookup_byte_offset(sp.lo);
let local_end = self.lookup_byte_offset(sp.hi);
- debug!(
- "find_width_of_character_at_span: local_begin=`{:?}`, local_end=`{:?}`",
- local_begin, local_end
- );
+ debug!("local_begin=`{:?}`, local_end=`{:?}`", local_begin, local_end);
if local_begin.sf.start_pos != local_end.sf.start_pos {
- debug!("find_width_of_character_at_span: begin and end are in different files");
+ debug!("begin and end are in different files");
return 1;
}
let start_index = local_begin.pos.to_usize();
let end_index = local_end.pos.to_usize();
- debug!(
- "find_width_of_character_at_span: start_index=`{:?}`, end_index=`{:?}`",
- start_index, end_index
- );
+ debug!("start_index=`{:?}`, end_index=`{:?}`", start_index, end_index);
// Disregard indexes that are at the start or end of their spans, they can't fit bigger
// characters.
if (!forwards && end_index == usize::MIN) || (forwards && start_index == usize::MAX) {
- debug!("find_width_of_character_at_span: start or end of span, cannot be multibyte");
+ debug!("start or end of span, cannot be multibyte");
return 1;
}
let source_len = (local_begin.sf.end_pos - local_begin.sf.start_pos).to_usize();
- debug!("find_width_of_character_at_span: source_len=`{:?}`", source_len);
+ debug!("source_len=`{:?}`", source_len);
// Ensure indexes are also not malformed.
if start_index > end_index || end_index > source_len - 1 {
- debug!("find_width_of_character_at_span: source indexes are malformed");
+ debug!("source indexes are malformed");
return 1;
}
} else {
return 1;
};
- debug!("find_width_of_character_at_span: snippet=`{:?}`", snippet);
+ debug!("snippet=`{:?}`", snippet);
let mut target = if forwards { end_index + 1 } else { end_index - 1 };
- debug!("find_width_of_character_at_span: initial target=`{:?}`", target);
+ debug!("initial target=`{:?}`", target);
while !snippet.is_char_boundary(target - start_index) && target < source_len {
target = if forwards {
}
}
};
- debug!("find_width_of_character_at_span: target=`{:?}`", target);
+ debug!("target=`{:?}`", target);
}
- debug!("find_width_of_character_at_span: final target=`{:?}`", target);
+ debug!("final target=`{:?}`", target);
if forwards { (target - end_index) as u32 } else { (end_index - target) as u32 }
}
pub fn ensure_source_file_source_present(&self, source_file: Lrc<SourceFile>) -> bool {
source_file.add_external_src(|| {
- match source_file.name {
- FileName::Real(ref name) if let Some(local_path) = name.local_path() => {
- self.file_loader.read_file(local_path).ok()
+ let FileName::Real(ref name) = source_file.name else {
+ return None;
+ };
+
+ let local_path: Cow<'_, Path> = match name {
+ RealFileName::LocalPath(local_path) => local_path.into(),
+ RealFileName::Remapped { local_path: Some(local_path), .. } => local_path.into(),
+ RealFileName::Remapped { local_path: None, virtual_name } => {
+ // The compiler produces better error messages if the sources of dependencies
+ // are available. Attempt to undo any path mapping so we can find remapped
+ // dependencies.
+ // We can only use the heuristic because `add_external_src` checks the file
+ // content hash.
+ self.path_mapping.reverse_map_prefix_heuristically(virtual_name)?.into()
}
- _ => None,
- }
+ };
+
+ self.file_loader.read_file(&local_path).ok()
})
}
}
}
}
+
+ /// Attempts to (heuristically) reverse a prefix mapping.
+ ///
+ /// Returns [`Some`] if there is exactly one mapping where the "to" part is
+ /// a prefix of `path` and has at least one non-empty
+ /// [`Normal`](path::Component::Normal) component. The component
+ /// restriction exists to avoid reverse mapping overly generic paths like
+ /// `/` or `.`).
+ ///
+ /// This is a heuristic and not guaranteed to return the actual original
+ /// path! Do not rely on the result unless you have other means to verify
+ /// that the mapping is correct (e.g. by checking the file content hash).
+ #[instrument(level = "debug", skip(self), ret)]
+ fn reverse_map_prefix_heuristically(&self, path: &Path) -> Option<PathBuf> {
+ let mut found = None;
+
+ for (from, to) in self.mapping.iter() {
+ let has_normal_component = to.components().any(|c| match c {
+ path::Component::Normal(s) => !s.is_empty(),
+ _ => false,
+ });
+
+ if !has_normal_component {
+ continue;
+ }
+
+ let Ok(rest) = path.strip_prefix(to) else {
+ continue;
+ };
+
+ if found.is_some() {
+ return None;
+ }
+
+ found = Some(from.join(rest));
+ }
+
+ found
+ }
}