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			100 lines
		
	
	
		
			3.3 KiB
		
	
	
	
		
			Rust
		
	
	
	
	
	
			
		
		
	
	
			100 lines
		
	
	
		
			3.3 KiB
		
	
	
	
		
			Rust
		
	
	
	
	
	
| use crate::generated_code;
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| use rustc_data_structures::sync::Lrc;
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| use rustc_lexer::{tokenize, TokenKind};
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| use rustc_session::Session;
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| use rustc_span::*;
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| 
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| #[derive(Clone)]
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| pub struct SpanUtils<'a> {
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|     pub sess: &'a Session,
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| }
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| 
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| impl<'a> SpanUtils<'a> {
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|     pub fn new(sess: &'a Session) -> SpanUtils<'a> {
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|         SpanUtils { sess }
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|     }
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| 
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|     pub fn make_filename_string(&self, file: &SourceFile) -> String {
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|         match &file.name {
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|             FileName::Real(name) if !file.name_was_remapped => {
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|                 let path = name.local_path();
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|                 if path.is_absolute() {
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|                     self.sess
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|                         .source_map()
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|                         .path_mapping()
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|                         .map_prefix(path.into())
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|                         .0
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|                         .display()
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|                         .to_string()
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|                 } else {
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|                     self.sess.working_dir.0.join(&path).display().to_string()
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|                 }
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|             }
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|             // If the file name is already remapped, we assume the user
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|             // configured it the way they wanted to, so use that directly
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|             filename => filename.to_string(),
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|         }
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|     }
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| 
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|     pub fn snippet(&self, span: Span) -> String {
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|         match self.sess.source_map().span_to_snippet(span) {
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|             Ok(s) => s,
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|             Err(_) => String::new(),
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|         }
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|     }
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| 
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|     /// Finds the span of `*` token withing the larger `span`.
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|     pub fn sub_span_of_star(&self, mut span: Span) -> Option<Span> {
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|         let begin = self.sess.source_map().lookup_byte_offset(span.lo());
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|         let end = self.sess.source_map().lookup_byte_offset(span.hi());
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|         // Make the range zero-length if the span is invalid.
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|         if begin.sf.start_pos != end.sf.start_pos {
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|             span = span.shrink_to_lo();
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|         }
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| 
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|         let sf = Lrc::clone(&begin.sf);
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| 
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|         self.sess.source_map().ensure_source_file_source_present(Lrc::clone(&sf));
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|         let src =
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|             sf.src.clone().or_else(|| sf.external_src.borrow().get_source().map(Lrc::clone))?;
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|         let to_index = |pos: BytePos| -> usize { (pos - sf.start_pos).0 as usize };
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|         let text = &src[to_index(span.lo())..to_index(span.hi())];
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|         let start_pos = {
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|             let mut pos = 0;
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|             tokenize(text)
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|                 .map(|token| {
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|                     let start = pos;
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|                     pos += token.len;
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|                     (start, token)
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|                 })
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|                 .find(|(_pos, token)| token.kind == TokenKind::Star)?
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|                 .0
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|         };
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|         let lo = span.lo() + BytePos(start_pos as u32);
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|         let hi = lo + BytePos(1);
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|         Some(span.with_lo(lo).with_hi(hi))
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|     }
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| 
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|     /// Return true if the span is generated code, and
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|     /// it is not a subspan of the root callsite.
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|     ///
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|     /// Used to filter out spans of minimal value,
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|     /// such as references to macro internal variables.
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|     pub fn filter_generated(&self, span: Span) -> bool {
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|         if generated_code(span) {
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|             return true;
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|         }
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| 
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|         //If the span comes from a fake source_file, filter it.
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|         !self.sess.source_map().lookup_char_pos(span.lo()).file.is_real_file()
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|     }
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| }
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| 
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| macro_rules! filter {
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|     ($util: expr, $parent: expr) => {
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|         if $util.filter_generated($parent) {
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|             return None;
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|         }
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|     };
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| }
 | 
