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use rustc::session::Session;
use generated_code;
use std::cell::Cell;
use std::env;
use std::path::Path;
use syntax::ast;
use syntax::parse::lexer::{self, StringReader};
use syntax::parse::token::{self, Token};
use syntax::symbol::keywords;
use syntax::tokenstream::TokenTree;
use syntax_pos::*;
#[derive(Clone)]
pub struct SpanUtils<'a> {
pub sess: &'a Session,
pub err_count: Cell<isize>,
}
impl<'a> SpanUtils<'a> {
pub fn new(sess: &'a Session) -> SpanUtils<'a> {
SpanUtils {
sess: sess,
err_count: Cell::new(0),
}
}
pub fn make_path_string(file_name: &str) -> String {
let path = Path::new(file_name);
if path.is_absolute() {
path.clone().display().to_string()
} else {
env::current_dir().unwrap().join(&path).display().to_string()
}
}
pub fn snippet(&self, span: Span) -> String {
match self.sess.codemap().span_to_snippet(span) {
Ok(s) => s,
Err(_) => String::new(),
}
}
pub fn retokenise_span(&self, span: Span) -> StringReader<'a> {
lexer::StringReader::retokenize(&self.sess.parse_sess, span)
}
pub fn span_for_last_ident(&self, span: Span) -> Option<Span> {
let mut result = None;
let mut toks = self.retokenise_span(span);
let mut bracket_count = 0;
loop {
let ts = toks.real_token();
if ts.tok == token::Eof {
return result
}
if bracket_count == 0 && (ts.tok.is_ident() || ts.tok.is_keyword(keywords::SelfValue)) {
result = Some(ts.sp);
}
bracket_count += match ts.tok {
token::Lt => 1,
token::Gt => -1,
token::BinOp(token::Shr) => -2,
_ => 0,
}
}
}
pub fn span_for_first_ident(&self, span: Span) -> Option<Span> {
let mut toks = self.retokenise_span(span);
let mut bracket_count = 0;
loop {
let ts = toks.real_token();
if ts.tok == token::Eof {
return None;
}
if bracket_count == 0 && (ts.tok.is_ident() || ts.tok.is_keyword(keywords::SelfValue)) {
return Some(ts.sp);
}
bracket_count += match ts.tok {
token::Lt => 1,
token::Gt => -1,
token::BinOp(token::Shr) => -2,
_ => 0,
}
}
}
pub fn sub_span_for_meth_name(&self, span: Span) -> Option<Span> {
let mut toks = self.retokenise_span(span);
let mut prev = toks.real_token();
let mut result = None;
let mut bracket_count = 0;
let mut prev_span = None;
while prev.tok != token::Eof {
prev_span = None;
let mut next = toks.real_token();
if (next.tok == token::OpenDelim(token::Paren) || next.tok == token::Lt) &&
bracket_count == 0 && prev.tok.is_ident() {
result = Some(prev.sp);
}
if bracket_count == 0 && next.tok == token::ModSep {
let old = prev;
prev = next;
next = toks.real_token();
if next.tok == token::Lt && old.tok.is_ident() {
result = Some(old.sp);
}
}
bracket_count += match prev.tok {
token::OpenDelim(token::Paren) | token::Lt => 1,
token::CloseDelim(token::Paren) | token::Gt => -1,
token::BinOp(token::Shr) => -2,
_ => 0,
};
if prev.tok.is_ident() && bracket_count == 0 {
prev_span = Some(prev.sp);
}
prev = next;
}
result.or(prev_span)
}
pub fn sub_span_for_type_name(&self, span: Span) -> Option<Span> {
let mut toks = self.retokenise_span(span);
let mut prev = toks.real_token();
let mut result = None;
let mut angle_count = 0;
let mut bracket_count = 0;
loop {
let next = toks.real_token();
if (next.tok == token::Lt || next.tok == token::Colon) &&
angle_count == 0 &&
bracket_count == 0 &&
prev.tok.is_ident() {
result = Some(prev.sp);
}
if bracket_count == 0 {
angle_count += match prev.tok {
token::Lt => 1,
token::Gt => -1,
token::BinOp(token::Shl) => 2,
token::BinOp(token::Shr) => -2,
_ => 0,
};
}
bracket_count += match prev.tok {
token::OpenDelim(token::Bracket) => 1,
token::CloseDelim(token::Bracket) => -1,
_ => 0,
};
if next.tok == token::Eof {
break;
}
prev = next;
}
if angle_count != 0 || bracket_count != 0 {
let loc = self.sess.codemap().lookup_char_pos(span.lo);
span_bug!(span,
"Mis-counted brackets when breaking path? Parsing '{}' \
in {}, line {}",
self.snippet(span),
loc.file.name,
loc.line);
}
if result.is_none() && prev.tok.is_ident() && angle_count == 0 {
return Some(prev.sp);
}
result
}
pub fn spans_with_brackets(&self, span: Span, nesting: isize, limit: isize) -> Vec<Span> {
let mut result: Vec<Span> = vec![];
let mut toks = self.retokenise_span(span);
let mut angle_count: isize = 0;
let mut bracket_count: isize = 0;
let mut found_ufcs_sep = false;
loop {
let ts = toks.real_token();
if ts.tok == token::Eof {
if angle_count != 0 || bracket_count != 0 {
if generated_code(span) {
return vec![];
}
let loc = self.sess.codemap().lookup_char_pos(span.lo);
span_bug!(span,
"Mis-counted brackets when breaking path? \
Parsing '{}' in {}, line {}",
self.snippet(span),
loc.file.name,
loc.line);
}
return result
}
if (result.len() as isize) == limit {
return result;
}
bracket_count += match ts.tok {
token::OpenDelim(token::Bracket) => 1,
token::CloseDelim(token::Bracket) => -1,
_ => 0,
};
if bracket_count > 0 {
continue;
}
angle_count += match ts.tok {
token::Lt => 1,
token::Gt => -1,
token::BinOp(token::Shl) => 2,
token::BinOp(token::Shr) => -2,
_ => 0,
};
if !found_ufcs_sep && angle_count == -1 {
found_ufcs_sep = true;
angle_count += 1;
}
if ts.tok.is_ident() && angle_count == nesting {
result.push(ts.sp);
}
}
}
pub fn signature_string_for_span(&self, span: Span) -> String {
let mut toks = self.retokenise_span(span);
toks.real_token();
let mut toks = toks.parse_all_token_trees().unwrap().trees();
let mut prev = toks.next().unwrap();
let first_span = prev.span();
let mut angle_count = 0;
for tok in toks {
if let TokenTree::Token(_, ref tok) = prev {
angle_count += match *tok {
token::Eof => { break; }
token::Lt => 1,
token::Gt => -1,
token::BinOp(token::Shl) => 2,
token::BinOp(token::Shr) => -2,
_ => 0,
};
}
if angle_count > 0 {
prev = tok;
continue;
}
if let TokenTree::Token(_, token::Semi) = tok {
return self.snippet(mk_sp(first_span.lo, prev.span().hi));
} else if let TokenTree::Delimited(_, ref d) = tok {
if d.delim == token::Brace {
return self.snippet(mk_sp(first_span.lo, prev.span().hi));
}
}
prev = tok;
}
self.snippet(span)
}
pub fn sub_span_before_token(&self, span: Span, tok: Token) -> Option<Span> {
let mut toks = self.retokenise_span(span);
let mut prev = toks.real_token();
loop {
if prev.tok == token::Eof {
return None;
}
let next = toks.real_token();
if next.tok == tok {
return Some(prev.sp);
}
prev = next;
}
}
pub fn sub_span_of_token(&self, span: Span, tok: Token) -> Option<Span> {
let mut toks = self.retokenise_span(span);
loop {
let next = toks.real_token();
if next.tok == token::Eof {
return None;
}
if next.tok == tok {
return Some(next.sp);
}
}
}
pub fn sub_span_after_keyword(&self, span: Span, keyword: keywords::Keyword) -> Option<Span> {
self.sub_span_after(span, |t| t.is_keyword(keyword))
}
pub fn sub_span_after_token(&self, span: Span, tok: Token) -> Option<Span> {
self.sub_span_after(span, |t| t == tok)
}
fn sub_span_after<F: Fn(Token) -> bool>(&self, span: Span, f: F) -> Option<Span> {
let mut toks = self.retokenise_span(span);
loop {
let ts = toks.real_token();
if ts.tok == token::Eof {
return None;
}
if f(ts.tok) {
let ts = toks.real_token();
if ts.tok == token::Eof {
return None
} else {
return Some(ts.sp);
}
}
}
}
pub fn spans_for_path_segments(&self, path: &ast::Path) -> Vec<Span> {
self.spans_with_brackets(path.span, 0, -1)
}
pub fn spans_for_ty_params(&self, span: Span, number: isize) -> Vec<Span> {
self.spans_with_brackets(span, 1, number)
}
pub fn report_span_err(&self, kind: &str, span: Span) {
let loc = self.sess.codemap().lookup_char_pos(span.lo);
info!("({}) Could not find sub_span in `{}` in {}, line {}",
kind,
self.snippet(span),
loc.file.name,
loc.line);
self.err_count.set(self.err_count.get() + 1);
if self.err_count.get() > 1000 {
bug!("span errors reached 1000, giving up");
}
}
pub fn span_for_macro_def_name(&self, span: Span) -> Option<Span> {
let mut toks = self.retokenise_span(span);
loop {
let ts = toks.real_token();
if ts.tok == token::Eof {
return None;
}
if ts.tok == token::Not {
let ts = toks.real_token();
if ts.tok.is_ident() {
return Some(ts.sp);
} else {
return None;
}
}
}
}
pub fn span_for_macro_use_name(&self, span:Span) -> Option<Span> {
let mut toks = self.retokenise_span(span);
let mut prev = toks.real_token();
loop {
if prev.tok == token::Eof {
return None;
}
let ts = toks.real_token();
if ts.tok == token::Not {
if prev.tok.is_ident() {
return Some(prev.sp);
} else {
return None;
}
}
prev = ts;
}
}
pub fn filter_generated(&self, sub_span: Option<Span>, parent: Span) -> bool {
if !generated_code(parent) {
if sub_span.is_none() {
return true;
}
return false;
}
if sub_span.is_none() {
return true;
}
if !self.sess.codemap().lookup_char_pos(parent.lo).file.is_real_file() {
return true;
}
let span = self.sess.codemap().source_callsite(parent);
!(span.contains(parent))
}
}
macro_rules! filter {
($util: expr, $span: ident, $parent: expr, None) => {
if $util.filter_generated($span, $parent) {
return None;
}
};
($util: expr, $span: ident, $parent: expr) => {
if $util.filter_generated($span, $parent) {
return;
}
};
}