| // Copyright 2012-2013 The Rust Project Developers. See the COPYRIGHT |
| // file at the top-level directory of this distribution and at |
| // http://rust-lang.org/COPYRIGHT. |
| // |
| // Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or |
| // http://www.apache.org/licenses/LICENSE-2.0> or the MIT license |
| // <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your |
| // option. This file may not be copied, modified, or distributed |
| // except according to those terms. |
| |
| //! The source positions and related helper functions |
| //! |
| //! # Note |
| //! |
| //! This API is completely unstable and subject to change. |
| |
| #![doc(html_logo_url = "https://www.rust-lang.org/logos/rust-logo-128x128-blk-v2.png", |
| html_favicon_url = "https://doc.rust-lang.org/favicon.ico", |
| html_root_url = "https://doc.rust-lang.org/nightly/")] |
| #![deny(warnings)] |
| |
| #![feature(const_fn)] |
| #![feature(custom_attribute)] |
| #![feature(i128_type)] |
| #![feature(optin_builtin_traits)] |
| #![allow(unused_attributes)] |
| #![feature(specialization)] |
| |
| use std::borrow::Cow; |
| use std::cell::{Cell, RefCell}; |
| use std::cmp::{self, Ordering}; |
| use std::fmt; |
| use std::hash::{Hasher, Hash}; |
| use std::ops::{Add, Sub}; |
| use std::path::PathBuf; |
| use std::rc::Rc; |
| |
| use rustc_data_structures::stable_hasher::StableHasher; |
| |
| extern crate rustc_data_structures; |
| |
| use serialize::{Encodable, Decodable, Encoder, Decoder}; |
| |
| extern crate serialize; |
| extern crate serialize as rustc_serialize; // used by deriving |
| |
| extern crate unicode_width; |
| |
| pub mod hygiene; |
| pub use hygiene::{SyntaxContext, ExpnInfo, ExpnFormat, NameAndSpan, CompilerDesugaringKind}; |
| |
| mod span_encoding; |
| pub use span_encoding::{Span, DUMMY_SP}; |
| |
| pub mod symbol; |
| |
| /// Differentiates between real files and common virtual files |
| #[derive(Debug, Eq, PartialEq, Clone, Ord, PartialOrd, Hash, RustcDecodable, RustcEncodable)] |
| pub enum FileName { |
| Real(PathBuf), |
| /// e.g. "std" macros |
| Macros(String), |
| /// call to `quote!` |
| QuoteExpansion, |
| /// Command line |
| Anon, |
| /// Hack in src/libsyntax/parse.rs |
| /// FIXME(jseyfried) |
| MacroExpansion, |
| ProcMacroSourceCode, |
| /// Strings provided as --cfg [cfgspec] stored in a crate_cfg |
| CfgSpec, |
| /// Custom sources for explicit parser calls from plugins and drivers |
| Custom(String), |
| } |
| |
| impl std::fmt::Display for FileName { |
| fn fmt(&self, fmt: &mut std::fmt::Formatter) -> std::fmt::Result { |
| use self::FileName::*; |
| match *self { |
| Real(ref path) => write!(fmt, "{}", path.display()), |
| Macros(ref name) => write!(fmt, "<{} macros>", name), |
| QuoteExpansion => write!(fmt, "<quote expansion>"), |
| MacroExpansion => write!(fmt, "<macro expansion>"), |
| Anon => write!(fmt, "<anon>"), |
| ProcMacroSourceCode => write!(fmt, "<proc-macro source code>"), |
| CfgSpec => write!(fmt, "cfgspec"), |
| Custom(ref s) => write!(fmt, "<{}>", s), |
| } |
| } |
| } |
| |
| impl From<PathBuf> for FileName { |
| fn from(p: PathBuf) -> Self { |
| assert!(!p.to_string_lossy().ends_with('>')); |
| FileName::Real(p) |
| } |
| } |
| |
| impl FileName { |
| pub fn is_real(&self) -> bool { |
| use self::FileName::*; |
| match *self { |
| Real(_) => true, |
| Macros(_) | |
| Anon | |
| MacroExpansion | |
| ProcMacroSourceCode | |
| CfgSpec | |
| Custom(_) | |
| QuoteExpansion => false, |
| } |
| } |
| |
| pub fn is_macros(&self) -> bool { |
| use self::FileName::*; |
| match *self { |
| Real(_) | |
| Anon | |
| MacroExpansion | |
| ProcMacroSourceCode | |
| CfgSpec | |
| Custom(_) | |
| QuoteExpansion => false, |
| Macros(_) => true, |
| } |
| } |
| } |
| |
| /// Spans represent a region of code, used for error reporting. Positions in spans |
| /// are *absolute* positions from the beginning of the codemap, not positions |
| /// relative to FileMaps. Methods on the CodeMap can be used to relate spans back |
| /// to the original source. |
| /// You must be careful if the span crosses more than one file - you will not be |
| /// able to use many of the functions on spans in codemap and you cannot assume |
| /// that the length of the span = hi - lo; there may be space in the BytePos |
| /// range between files. |
| /// |
| /// `SpanData` is public because `Span` uses a thread-local interner and can't be |
| /// sent to other threads, but some pieces of performance infra run in a separate thread. |
| /// Using `Span` is generally preferred. |
| #[derive(Clone, Copy, Hash, PartialEq, Eq, Ord, PartialOrd)] |
| pub struct SpanData { |
| pub lo: BytePos, |
| pub hi: BytePos, |
| /// Information about where the macro came from, if this piece of |
| /// code was created by a macro expansion. |
| pub ctxt: SyntaxContext, |
| } |
| |
| impl SpanData { |
| #[inline] |
| pub fn with_lo(&self, lo: BytePos) -> Span { |
| Span::new(lo, self.hi, self.ctxt) |
| } |
| #[inline] |
| pub fn with_hi(&self, hi: BytePos) -> Span { |
| Span::new(self.lo, hi, self.ctxt) |
| } |
| #[inline] |
| pub fn with_ctxt(&self, ctxt: SyntaxContext) -> Span { |
| Span::new(self.lo, self.hi, ctxt) |
| } |
| } |
| |
| // The interner in thread-local, so `Span` shouldn't move between threads. |
| impl !Send for Span {} |
| impl !Sync for Span {} |
| |
| impl PartialOrd for Span { |
| fn partial_cmp(&self, rhs: &Self) -> Option<Ordering> { |
| PartialOrd::partial_cmp(&self.data(), &rhs.data()) |
| } |
| } |
| impl Ord for Span { |
| fn cmp(&self, rhs: &Self) -> Ordering { |
| Ord::cmp(&self.data(), &rhs.data()) |
| } |
| } |
| |
| /// A collection of spans. Spans have two orthogonal attributes: |
| /// |
| /// - they can be *primary spans*. In this case they are the locus of |
| /// the error, and would be rendered with `^^^`. |
| /// - they can have a *label*. In this case, the label is written next |
| /// to the mark in the snippet when we render. |
| #[derive(Clone, Debug, Hash, PartialEq, Eq, RustcEncodable, RustcDecodable)] |
| pub struct MultiSpan { |
| primary_spans: Vec<Span>, |
| span_labels: Vec<(Span, String)>, |
| } |
| |
| impl Span { |
| #[inline] |
| pub fn lo(self) -> BytePos { |
| self.data().lo |
| } |
| #[inline] |
| pub fn with_lo(self, lo: BytePos) -> Span { |
| self.data().with_lo(lo) |
| } |
| #[inline] |
| pub fn hi(self) -> BytePos { |
| self.data().hi |
| } |
| #[inline] |
| pub fn with_hi(self, hi: BytePos) -> Span { |
| self.data().with_hi(hi) |
| } |
| #[inline] |
| pub fn ctxt(self) -> SyntaxContext { |
| self.data().ctxt |
| } |
| #[inline] |
| pub fn with_ctxt(self, ctxt: SyntaxContext) -> Span { |
| self.data().with_ctxt(ctxt) |
| } |
| |
| /// Returns a new span representing just the end-point of this span |
| pub fn end_point(self) -> Span { |
| let span = self.data(); |
| let lo = cmp::max(span.hi.0 - 1, span.lo.0); |
| span.with_lo(BytePos(lo)) |
| } |
| |
| /// Returns a new span representing the next character after the end-point of this span |
| pub fn next_point(self) -> Span { |
| let span = self.data(); |
| let lo = cmp::max(span.hi.0, span.lo.0 + 1); |
| Span::new(BytePos(lo), BytePos(lo), span.ctxt) |
| } |
| |
| /// Returns `self` if `self` is not the dummy span, and `other` otherwise. |
| pub fn substitute_dummy(self, other: Span) -> Span { |
| if self.source_equal(&DUMMY_SP) { other } else { self } |
| } |
| |
| /// Return true if `self` fully encloses `other`. |
| pub fn contains(self, other: Span) -> bool { |
| let span = self.data(); |
| let other = other.data(); |
| span.lo <= other.lo && other.hi <= span.hi |
| } |
| |
| /// Return true if the spans are equal with regards to the source text. |
| /// |
| /// Use this instead of `==` when either span could be generated code, |
| /// and you only care that they point to the same bytes of source text. |
| pub fn source_equal(&self, other: &Span) -> bool { |
| let span = self.data(); |
| let other = other.data(); |
| span.lo == other.lo && span.hi == other.hi |
| } |
| |
| /// Returns `Some(span)`, where the start is trimmed by the end of `other` |
| pub fn trim_start(self, other: Span) -> Option<Span> { |
| let span = self.data(); |
| let other = other.data(); |
| if span.hi > other.hi { |
| Some(span.with_lo(cmp::max(span.lo, other.hi))) |
| } else { |
| None |
| } |
| } |
| |
| /// Return the source span - this is either the supplied span, or the span for |
| /// the macro callsite that expanded to it. |
| pub fn source_callsite(self) -> Span { |
| self.ctxt().outer().expn_info().map(|info| info.call_site.source_callsite()).unwrap_or(self) |
| } |
| |
| /// Return the source callee. |
| /// |
| /// Returns None if the supplied span has no expansion trace, |
| /// else returns the NameAndSpan for the macro definition |
| /// corresponding to the source callsite. |
| pub fn source_callee(self) -> Option<NameAndSpan> { |
| fn source_callee(info: ExpnInfo) -> NameAndSpan { |
| match info.call_site.ctxt().outer().expn_info() { |
| Some(info) => source_callee(info), |
| None => info.callee, |
| } |
| } |
| self.ctxt().outer().expn_info().map(source_callee) |
| } |
| |
| /// Check if a span is "internal" to a macro in which #[unstable] |
| /// items can be used (that is, a macro marked with |
| /// `#[allow_internal_unstable]`). |
| pub fn allows_unstable(&self) -> bool { |
| match self.ctxt().outer().expn_info() { |
| Some(info) => info.callee.allow_internal_unstable, |
| None => false, |
| } |
| } |
| |
| /// Check if this span arises from a compiler desugaring of kind `kind`. |
| pub fn is_compiler_desugaring(&self, kind: CompilerDesugaringKind) -> bool { |
| match self.ctxt().outer().expn_info() { |
| Some(info) => match info.callee.format { |
| ExpnFormat::CompilerDesugaring(k) => k == kind, |
| _ => false, |
| }, |
| None => false, |
| } |
| } |
| |
| /// Return the compiler desugaring that created this span, or None |
| /// if this span is not from a desugaring. |
| pub fn compiler_desugaring_kind(&self) -> Option<CompilerDesugaringKind> { |
| match self.ctxt().outer().expn_info() { |
| Some(info) => match info.callee.format { |
| ExpnFormat::CompilerDesugaring(k) => Some(k), |
| _ => None |
| }, |
| None => None |
| } |
| } |
| |
| /// Check if a span is "internal" to a macro in which `unsafe` |
| /// can be used without triggering the `unsafe_code` lint |
| // (that is, a macro marked with `#[allow_internal_unsafe]`). |
| pub fn allows_unsafe(&self) -> bool { |
| match self.ctxt().outer().expn_info() { |
| Some(info) => info.callee.allow_internal_unsafe, |
| None => false, |
| } |
| } |
| |
| pub fn macro_backtrace(mut self) -> Vec<MacroBacktrace> { |
| let mut prev_span = DUMMY_SP; |
| let mut result = vec![]; |
| loop { |
| let info = match self.ctxt().outer().expn_info() { |
| Some(info) => info, |
| None => break, |
| }; |
| |
| let (pre, post) = match info.callee.format { |
| ExpnFormat::MacroAttribute(..) => ("#[", "]"), |
| ExpnFormat::MacroBang(..) => ("", "!"), |
| ExpnFormat::CompilerDesugaring(..) => ("desugaring of `", "`"), |
| }; |
| let macro_decl_name = format!("{}{}{}", pre, info.callee.name(), post); |
| let def_site_span = info.callee.span; |
| |
| // Don't print recursive invocations |
| if !info.call_site.source_equal(&prev_span) { |
| result.push(MacroBacktrace { |
| call_site: info.call_site, |
| macro_decl_name, |
| def_site_span, |
| }); |
| } |
| |
| prev_span = self; |
| self = info.call_site; |
| } |
| result |
| } |
| |
| /// Return a `Span` that would enclose both `self` and `end`. |
| pub fn to(self, end: Span) -> Span { |
| let span = self.data(); |
| let end = end.data(); |
| Span::new( |
| cmp::min(span.lo, end.lo), |
| cmp::max(span.hi, end.hi), |
| // FIXME(jseyfried): self.ctxt should always equal end.ctxt here (c.f. issue #23480) |
| if span.ctxt == SyntaxContext::empty() { end.ctxt } else { span.ctxt }, |
| ) |
| } |
| |
| /// Return a `Span` between the end of `self` to the beginning of `end`. |
| pub fn between(self, end: Span) -> Span { |
| let span = self.data(); |
| let end = end.data(); |
| Span::new( |
| span.hi, |
| end.lo, |
| if end.ctxt == SyntaxContext::empty() { end.ctxt } else { span.ctxt }, |
| ) |
| } |
| |
| /// Return a `Span` between the beginning of `self` to the beginning of `end`. |
| pub fn until(self, end: Span) -> Span { |
| let span = self.data(); |
| let end = end.data(); |
| Span::new( |
| span.lo, |
| end.lo, |
| if end.ctxt == SyntaxContext::empty() { end.ctxt } else { span.ctxt }, |
| ) |
| } |
| } |
| |
| #[derive(Clone, Debug)] |
| pub struct SpanLabel { |
| /// The span we are going to include in the final snippet. |
| pub span: Span, |
| |
| /// Is this a primary span? This is the "locus" of the message, |
| /// and is indicated with a `^^^^` underline, versus `----`. |
| pub is_primary: bool, |
| |
| /// What label should we attach to this span (if any)? |
| pub label: Option<String>, |
| } |
| |
| impl Default for Span { |
| fn default() -> Self { |
| DUMMY_SP |
| } |
| } |
| |
| impl serialize::UseSpecializedEncodable for Span { |
| fn default_encode<S: Encoder>(&self, s: &mut S) -> Result<(), S::Error> { |
| let span = self.data(); |
| s.emit_struct("Span", 2, |s| { |
| s.emit_struct_field("lo", 0, |s| { |
| span.lo.encode(s) |
| })?; |
| |
| s.emit_struct_field("hi", 1, |s| { |
| span.hi.encode(s) |
| }) |
| }) |
| } |
| } |
| |
| impl serialize::UseSpecializedDecodable for Span { |
| fn default_decode<D: Decoder>(d: &mut D) -> Result<Span, D::Error> { |
| d.read_struct("Span", 2, |d| { |
| let lo = d.read_struct_field("lo", 0, Decodable::decode)?; |
| let hi = d.read_struct_field("hi", 1, Decodable::decode)?; |
| Ok(Span::new(lo, hi, NO_EXPANSION)) |
| }) |
| } |
| } |
| |
| fn default_span_debug(span: Span, f: &mut fmt::Formatter) -> fmt::Result { |
| f.debug_struct("Span") |
| .field("lo", &span.lo()) |
| .field("hi", &span.hi()) |
| .field("ctxt", &span.ctxt()) |
| .finish() |
| } |
| |
| impl fmt::Debug for Span { |
| fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result { |
| SPAN_DEBUG.with(|span_debug| span_debug.get()(*self, f)) |
| } |
| } |
| |
| impl fmt::Debug for SpanData { |
| fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result { |
| SPAN_DEBUG.with(|span_debug| span_debug.get()(Span::new(self.lo, self.hi, self.ctxt), f)) |
| } |
| } |
| |
| impl MultiSpan { |
| pub fn new() -> MultiSpan { |
| MultiSpan { |
| primary_spans: vec![], |
| span_labels: vec![] |
| } |
| } |
| |
| pub fn from_span(primary_span: Span) -> MultiSpan { |
| MultiSpan { |
| primary_spans: vec![primary_span], |
| span_labels: vec![] |
| } |
| } |
| |
| pub fn from_spans(vec: Vec<Span>) -> MultiSpan { |
| MultiSpan { |
| primary_spans: vec, |
| span_labels: vec![] |
| } |
| } |
| |
| pub fn push_span_label(&mut self, span: Span, label: String) { |
| self.span_labels.push((span, label)); |
| } |
| |
| /// Selects the first primary span (if any) |
| pub fn primary_span(&self) -> Option<Span> { |
| self.primary_spans.first().cloned() |
| } |
| |
| /// Returns all primary spans. |
| pub fn primary_spans(&self) -> &[Span] { |
| &self.primary_spans |
| } |
| |
| /// Replaces all occurrences of one Span with another. Used to move Spans in areas that don't |
| /// display well (like std macros). Returns true if replacements occurred. |
| pub fn replace(&mut self, before: Span, after: Span) -> bool { |
| let mut replacements_occurred = false; |
| for primary_span in &mut self.primary_spans { |
| if *primary_span == before { |
| *primary_span = after; |
| replacements_occurred = true; |
| } |
| } |
| for span_label in &mut self.span_labels { |
| if span_label.0 == before { |
| span_label.0 = after; |
| replacements_occurred = true; |
| } |
| } |
| replacements_occurred |
| } |
| |
| /// Returns the strings to highlight. We always ensure that there |
| /// is an entry for each of the primary spans -- for each primary |
| /// span P, if there is at least one label with span P, we return |
| /// those labels (marked as primary). But otherwise we return |
| /// `SpanLabel` instances with empty labels. |
| pub fn span_labels(&self) -> Vec<SpanLabel> { |
| let is_primary = |span| self.primary_spans.contains(&span); |
| let mut span_labels = vec![]; |
| |
| for &(span, ref label) in &self.span_labels { |
| span_labels.push(SpanLabel { |
| span, |
| is_primary: is_primary(span), |
| label: Some(label.clone()) |
| }); |
| } |
| |
| for &span in &self.primary_spans { |
| if !span_labels.iter().any(|sl| sl.span == span) { |
| span_labels.push(SpanLabel { |
| span, |
| is_primary: true, |
| label: None |
| }); |
| } |
| } |
| |
| span_labels |
| } |
| } |
| |
| impl From<Span> for MultiSpan { |
| fn from(span: Span) -> MultiSpan { |
| MultiSpan::from_span(span) |
| } |
| } |
| |
| impl From<Vec<Span>> for MultiSpan { |
| fn from(spans: Vec<Span>) -> MultiSpan { |
| MultiSpan::from_spans(spans) |
| } |
| } |
| |
| pub const NO_EXPANSION: SyntaxContext = SyntaxContext::empty(); |
| |
| /// Identifies an offset of a multi-byte character in a FileMap |
| #[derive(Copy, Clone, RustcEncodable, RustcDecodable, Eq, PartialEq)] |
| pub struct MultiByteChar { |
| /// The absolute offset of the character in the CodeMap |
| pub pos: BytePos, |
| /// The number of bytes, >=2 |
| pub bytes: usize, |
| } |
| |
| /// Identifies an offset of a non-narrow character in a FileMap |
| #[derive(Copy, Clone, RustcEncodable, RustcDecodable, Eq, PartialEq)] |
| pub enum NonNarrowChar { |
| /// Represents a zero-width character |
| ZeroWidth(BytePos), |
| /// Represents a wide (fullwidth) character |
| Wide(BytePos), |
| /// Represents a tab character, represented visually with a width of 4 characters |
| Tab(BytePos), |
| } |
| |
| impl NonNarrowChar { |
| fn new(pos: BytePos, width: usize) -> Self { |
| match width { |
| 0 => NonNarrowChar::ZeroWidth(pos), |
| 2 => NonNarrowChar::Wide(pos), |
| 4 => NonNarrowChar::Tab(pos), |
| _ => panic!("width {} given for non-narrow character", width), |
| } |
| } |
| |
| /// Returns the absolute offset of the character in the CodeMap |
| pub fn pos(&self) -> BytePos { |
| match *self { |
| NonNarrowChar::ZeroWidth(p) | |
| NonNarrowChar::Wide(p) | |
| NonNarrowChar::Tab(p) => p, |
| } |
| } |
| |
| /// Returns the width of the character, 0 (zero-width) or 2 (wide) |
| pub fn width(&self) -> usize { |
| match *self { |
| NonNarrowChar::ZeroWidth(_) => 0, |
| NonNarrowChar::Wide(_) => 2, |
| NonNarrowChar::Tab(_) => 4, |
| } |
| } |
| } |
| |
| impl Add<BytePos> for NonNarrowChar { |
| type Output = Self; |
| |
| fn add(self, rhs: BytePos) -> Self { |
| match self { |
| NonNarrowChar::ZeroWidth(pos) => NonNarrowChar::ZeroWidth(pos + rhs), |
| NonNarrowChar::Wide(pos) => NonNarrowChar::Wide(pos + rhs), |
| NonNarrowChar::Tab(pos) => NonNarrowChar::Tab(pos + rhs), |
| } |
| } |
| } |
| |
| impl Sub<BytePos> for NonNarrowChar { |
| type Output = Self; |
| |
| fn sub(self, rhs: BytePos) -> Self { |
| match self { |
| NonNarrowChar::ZeroWidth(pos) => NonNarrowChar::ZeroWidth(pos - rhs), |
| NonNarrowChar::Wide(pos) => NonNarrowChar::Wide(pos - rhs), |
| NonNarrowChar::Tab(pos) => NonNarrowChar::Tab(pos - rhs), |
| } |
| } |
| } |
| |
| /// The state of the lazy external source loading mechanism of a FileMap. |
| #[derive(PartialEq, Eq, Clone)] |
| pub enum ExternalSource { |
| /// The external source has been loaded already. |
| Present(String), |
| /// No attempt has been made to load the external source. |
| AbsentOk, |
| /// A failed attempt has been made to load the external source. |
| AbsentErr, |
| /// No external source has to be loaded, since the FileMap represents a local crate. |
| Unneeded, |
| } |
| |
| impl ExternalSource { |
| pub fn is_absent(&self) -> bool { |
| match *self { |
| ExternalSource::Present(_) => false, |
| _ => true, |
| } |
| } |
| |
| pub fn get_source(&self) -> Option<&str> { |
| match *self { |
| ExternalSource::Present(ref src) => Some(src), |
| _ => None, |
| } |
| } |
| } |
| |
| /// A single source in the CodeMap. |
| #[derive(Clone)] |
| pub struct FileMap { |
| /// The name of the file that the source came from, source that doesn't |
| /// originate from files has names between angle brackets by convention, |
| /// e.g. `<anon>` |
| pub name: FileName, |
| /// True if the `name` field above has been modified by -Zremap-path-prefix |
| pub name_was_remapped: bool, |
| /// The unmapped path of the file that the source came from. |
| /// Set to `None` if the FileMap was imported from an external crate. |
| pub unmapped_path: Option<FileName>, |
| /// Indicates which crate this FileMap was imported from. |
| pub crate_of_origin: u32, |
| /// The complete source code |
| pub src: Option<Rc<String>>, |
| /// The source code's hash |
| pub src_hash: u128, |
| /// The external source code (used for external crates, which will have a `None` |
| /// value as `self.src`. |
| pub external_src: RefCell<ExternalSource>, |
| /// The start position of this source in the CodeMap |
| pub start_pos: BytePos, |
| /// The end position of this source in the CodeMap |
| pub end_pos: BytePos, |
| /// Locations of lines beginnings in the source code |
| pub lines: RefCell<Vec<BytePos>>, |
| /// Locations of multi-byte characters in the source code |
| pub multibyte_chars: RefCell<Vec<MultiByteChar>>, |
| /// Width of characters that are not narrow in the source code |
| pub non_narrow_chars: RefCell<Vec<NonNarrowChar>>, |
| /// A hash of the filename, used for speeding up the incr. comp. hashing. |
| pub name_hash: u128, |
| } |
| |
| impl Encodable for FileMap { |
| fn encode<S: Encoder>(&self, s: &mut S) -> Result<(), S::Error> { |
| s.emit_struct("FileMap", 8, |s| { |
| s.emit_struct_field("name", 0, |s| self.name.encode(s))?; |
| s.emit_struct_field("name_was_remapped", 1, |s| self.name_was_remapped.encode(s))?; |
| s.emit_struct_field("src_hash", 2, |s| self.src_hash.encode(s))?; |
| s.emit_struct_field("start_pos", 4, |s| self.start_pos.encode(s))?; |
| s.emit_struct_field("end_pos", 5, |s| self.end_pos.encode(s))?; |
| s.emit_struct_field("lines", 6, |s| { |
| let lines = self.lines.borrow(); |
| // store the length |
| s.emit_u32(lines.len() as u32)?; |
| |
| if !lines.is_empty() { |
| // In order to preserve some space, we exploit the fact that |
| // the lines list is sorted and individual lines are |
| // probably not that long. Because of that we can store lines |
| // as a difference list, using as little space as possible |
| // for the differences. |
| let max_line_length = if lines.len() == 1 { |
| 0 |
| } else { |
| lines.windows(2) |
| .map(|w| w[1] - w[0]) |
| .map(|bp| bp.to_usize()) |
| .max() |
| .unwrap() |
| }; |
| |
| let bytes_per_diff: u8 = match max_line_length { |
| 0 ... 0xFF => 1, |
| 0x100 ... 0xFFFF => 2, |
| _ => 4 |
| }; |
| |
| // Encode the number of bytes used per diff. |
| bytes_per_diff.encode(s)?; |
| |
| // Encode the first element. |
| lines[0].encode(s)?; |
| |
| let diff_iter = (&lines[..]).windows(2) |
| .map(|w| (w[1] - w[0])); |
| |
| match bytes_per_diff { |
| 1 => for diff in diff_iter { (diff.0 as u8).encode(s)? }, |
| 2 => for diff in diff_iter { (diff.0 as u16).encode(s)? }, |
| 4 => for diff in diff_iter { diff.0.encode(s)? }, |
| _ => unreachable!() |
| } |
| } |
| |
| Ok(()) |
| })?; |
| s.emit_struct_field("multibyte_chars", 7, |s| { |
| (*self.multibyte_chars.borrow()).encode(s) |
| })?; |
| s.emit_struct_field("non_narrow_chars", 8, |s| { |
| (*self.non_narrow_chars.borrow()).encode(s) |
| })?; |
| s.emit_struct_field("name_hash", 9, |s| { |
| self.name_hash.encode(s) |
| }) |
| }) |
| } |
| } |
| |
| impl Decodable for FileMap { |
| fn decode<D: Decoder>(d: &mut D) -> Result<FileMap, D::Error> { |
| |
| d.read_struct("FileMap", 8, |d| { |
| let name: FileName = d.read_struct_field("name", 0, |d| Decodable::decode(d))?; |
| let name_was_remapped: bool = |
| d.read_struct_field("name_was_remapped", 1, |d| Decodable::decode(d))?; |
| let src_hash: u128 = |
| d.read_struct_field("src_hash", 2, |d| Decodable::decode(d))?; |
| let start_pos: BytePos = |
| d.read_struct_field("start_pos", 4, |d| Decodable::decode(d))?; |
| let end_pos: BytePos = d.read_struct_field("end_pos", 5, |d| Decodable::decode(d))?; |
| let lines: Vec<BytePos> = d.read_struct_field("lines", 6, |d| { |
| let num_lines: u32 = Decodable::decode(d)?; |
| let mut lines = Vec::with_capacity(num_lines as usize); |
| |
| if num_lines > 0 { |
| // Read the number of bytes used per diff. |
| let bytes_per_diff: u8 = Decodable::decode(d)?; |
| |
| // Read the first element. |
| let mut line_start: BytePos = Decodable::decode(d)?; |
| lines.push(line_start); |
| |
| for _ in 1..num_lines { |
| let diff = match bytes_per_diff { |
| 1 => d.read_u8()? as u32, |
| 2 => d.read_u16()? as u32, |
| 4 => d.read_u32()?, |
| _ => unreachable!() |
| }; |
| |
| line_start = line_start + BytePos(diff); |
| |
| lines.push(line_start); |
| } |
| } |
| |
| Ok(lines) |
| })?; |
| let multibyte_chars: Vec<MultiByteChar> = |
| d.read_struct_field("multibyte_chars", 7, |d| Decodable::decode(d))?; |
| let non_narrow_chars: Vec<NonNarrowChar> = |
| d.read_struct_field("non_narrow_chars", 8, |d| Decodable::decode(d))?; |
| let name_hash: u128 = |
| d.read_struct_field("name_hash", 9, |d| Decodable::decode(d))?; |
| Ok(FileMap { |
| name, |
| name_was_remapped, |
| unmapped_path: None, |
| // `crate_of_origin` has to be set by the importer. |
| // This value matches up with rustc::hir::def_id::INVALID_CRATE. |
| // That constant is not available here unfortunately :( |
| crate_of_origin: ::std::u32::MAX - 1, |
| start_pos, |
| end_pos, |
| src: None, |
| src_hash, |
| external_src: RefCell::new(ExternalSource::AbsentOk), |
| lines: RefCell::new(lines), |
| multibyte_chars: RefCell::new(multibyte_chars), |
| non_narrow_chars: RefCell::new(non_narrow_chars), |
| name_hash, |
| }) |
| }) |
| } |
| } |
| |
| impl fmt::Debug for FileMap { |
| fn fmt(&self, fmt: &mut fmt::Formatter) -> fmt::Result { |
| write!(fmt, "FileMap({})", self.name) |
| } |
| } |
| |
| impl FileMap { |
| pub fn new(name: FileName, |
| name_was_remapped: bool, |
| unmapped_path: FileName, |
| mut src: String, |
| start_pos: BytePos) -> FileMap { |
| remove_bom(&mut src); |
| |
| let src_hash = { |
| let mut hasher: StableHasher<u128> = StableHasher::new(); |
| hasher.write(src.as_bytes()); |
| hasher.finish() |
| }; |
| let name_hash = { |
| let mut hasher: StableHasher<u128> = StableHasher::new(); |
| name.hash(&mut hasher); |
| hasher.finish() |
| }; |
| let end_pos = start_pos.to_usize() + src.len(); |
| |
| FileMap { |
| name, |
| name_was_remapped, |
| unmapped_path: Some(unmapped_path), |
| crate_of_origin: 0, |
| src: Some(Rc::new(src)), |
| src_hash, |
| external_src: RefCell::new(ExternalSource::Unneeded), |
| start_pos, |
| end_pos: Pos::from_usize(end_pos), |
| lines: RefCell::new(Vec::new()), |
| multibyte_chars: RefCell::new(Vec::new()), |
| non_narrow_chars: RefCell::new(Vec::new()), |
| name_hash, |
| } |
| } |
| |
| /// EFFECT: register a start-of-line offset in the |
| /// table of line-beginnings. |
| /// UNCHECKED INVARIANT: these offsets must be added in the right |
| /// order and must be in the right places; there is shared knowledge |
| /// about what ends a line between this file and parse.rs |
| /// WARNING: pos param here is the offset relative to start of CodeMap, |
| /// and CodeMap will append a newline when adding a filemap without a newline at the end, |
| /// so the safe way to call this is with value calculated as |
| /// filemap.start_pos + newline_offset_relative_to_the_start_of_filemap. |
| pub fn next_line(&self, pos: BytePos) { |
| // the new charpos must be > the last one (or it's the first one). |
| let mut lines = self.lines.borrow_mut(); |
| let line_len = lines.len(); |
| assert!(line_len == 0 || ((*lines)[line_len - 1] < pos)); |
| lines.push(pos); |
| } |
| |
| /// Add externally loaded source. |
| /// If the hash of the input doesn't match or no input is supplied via None, |
| /// it is interpreted as an error and the corresponding enum variant is set. |
| /// The return value signifies whether some kind of source is present. |
| pub fn add_external_src<F>(&self, get_src: F) -> bool |
| where F: FnOnce() -> Option<String> |
| { |
| if *self.external_src.borrow() == ExternalSource::AbsentOk { |
| let src = get_src(); |
| let mut external_src = self.external_src.borrow_mut(); |
| if let Some(src) = src { |
| let mut hasher: StableHasher<u128> = StableHasher::new(); |
| hasher.write(src.as_bytes()); |
| |
| if hasher.finish() == self.src_hash { |
| *external_src = ExternalSource::Present(src); |
| return true; |
| } |
| } else { |
| *external_src = ExternalSource::AbsentErr; |
| } |
| |
| false |
| } else { |
| self.src.is_some() || self.external_src.borrow().get_source().is_some() |
| } |
| } |
| |
| /// Get a line from the list of pre-computed line-beginnings. |
| /// The line number here is 0-based. |
| pub fn get_line(&self, line_number: usize) -> Option<Cow<str>> { |
| fn get_until_newline(src: &str, begin: usize) -> &str { |
| // We can't use `lines.get(line_number+1)` because we might |
| // be parsing when we call this function and thus the current |
| // line is the last one we have line info for. |
| let slice = &src[begin..]; |
| match slice.find('\n') { |
| Some(e) => &slice[..e], |
| None => slice |
| } |
| } |
| |
| let lines = self.lines.borrow(); |
| let line = if let Some(line) = lines.get(line_number) { |
| line |
| } else { |
| return None; |
| }; |
| let begin: BytePos = *line - self.start_pos; |
| let begin = begin.to_usize(); |
| |
| if let Some(ref src) = self.src { |
| Some(Cow::from(get_until_newline(src, begin))) |
| } else if let Some(src) = self.external_src.borrow().get_source() { |
| Some(Cow::Owned(String::from(get_until_newline(src, begin)))) |
| } else { |
| None |
| } |
| } |
| |
| pub fn record_multibyte_char(&self, pos: BytePos, bytes: usize) { |
| assert!(bytes >=2 && bytes <= 4); |
| let mbc = MultiByteChar { |
| pos, |
| bytes, |
| }; |
| self.multibyte_chars.borrow_mut().push(mbc); |
| } |
| |
| pub fn record_width(&self, pos: BytePos, ch: char) { |
| let width = match ch { |
| '\t' => |
| // Tabs will consume 4 columns. |
| 4, |
| '\n' => |
| // Make newlines take one column so that displayed spans can point them. |
| 1, |
| ch => |
| // Assume control characters are zero width. |
| // FIXME: How can we decide between `width` and `width_cjk`? |
| unicode_width::UnicodeWidthChar::width(ch).unwrap_or(0), |
| }; |
| // Only record non-narrow characters. |
| if width != 1 { |
| self.non_narrow_chars.borrow_mut().push(NonNarrowChar::new(pos, width)); |
| } |
| } |
| |
| pub fn is_real_file(&self) -> bool { |
| self.name.is_real() |
| } |
| |
| pub fn is_imported(&self) -> bool { |
| self.src.is_none() |
| } |
| |
| pub fn byte_length(&self) -> u32 { |
| self.end_pos.0 - self.start_pos.0 |
| } |
| pub fn count_lines(&self) -> usize { |
| self.lines.borrow().len() |
| } |
| |
| /// Find the line containing the given position. The return value is the |
| /// index into the `lines` array of this FileMap, not the 1-based line |
| /// number. If the filemap is empty or the position is located before the |
| /// first line, None is returned. |
| pub fn lookup_line(&self, pos: BytePos) -> Option<usize> { |
| let lines = self.lines.borrow(); |
| if lines.len() == 0 { |
| return None; |
| } |
| |
| let line_index = lookup_line(&lines[..], pos); |
| assert!(line_index < lines.len() as isize); |
| if line_index >= 0 { |
| Some(line_index as usize) |
| } else { |
| None |
| } |
| } |
| |
| pub fn line_bounds(&self, line_index: usize) -> (BytePos, BytePos) { |
| if self.start_pos == self.end_pos { |
| return (self.start_pos, self.end_pos); |
| } |
| |
| let lines = self.lines.borrow(); |
| assert!(line_index < lines.len()); |
| if line_index == (lines.len() - 1) { |
| (lines[line_index], self.end_pos) |
| } else { |
| (lines[line_index], lines[line_index + 1]) |
| } |
| } |
| |
| #[inline] |
| pub fn contains(&self, byte_pos: BytePos) -> bool { |
| byte_pos >= self.start_pos && byte_pos <= self.end_pos |
| } |
| } |
| |
| /// Remove utf-8 BOM if any. |
| fn remove_bom(src: &mut String) { |
| if src.starts_with("\u{feff}") { |
| src.drain(..3); |
| } |
| } |
| |
| // _____________________________________________________________________________ |
| // Pos, BytePos, CharPos |
| // |
| |
| pub trait Pos { |
| fn from_usize(n: usize) -> Self; |
| fn to_usize(&self) -> usize; |
| } |
| |
| /// A byte offset. Keep this small (currently 32-bits), as AST contains |
| /// a lot of them. |
| #[derive(Clone, Copy, PartialEq, Eq, Hash, PartialOrd, Ord, Debug)] |
| pub struct BytePos(pub u32); |
| |
| /// A character offset. Because of multibyte utf8 characters, a byte offset |
| /// is not equivalent to a character offset. The CodeMap will convert BytePos |
| /// values to CharPos values as necessary. |
| #[derive(Copy, Clone, PartialEq, Eq, Hash, PartialOrd, Ord, Debug)] |
| pub struct CharPos(pub usize); |
| |
| // FIXME: Lots of boilerplate in these impls, but so far my attempts to fix |
| // have been unsuccessful |
| |
| impl Pos for BytePos { |
| fn from_usize(n: usize) -> BytePos { BytePos(n as u32) } |
| fn to_usize(&self) -> usize { let BytePos(n) = *self; n as usize } |
| } |
| |
| impl Add for BytePos { |
| type Output = BytePos; |
| |
| fn add(self, rhs: BytePos) -> BytePos { |
| BytePos((self.to_usize() + rhs.to_usize()) as u32) |
| } |
| } |
| |
| impl Sub for BytePos { |
| type Output = BytePos; |
| |
| fn sub(self, rhs: BytePos) -> BytePos { |
| BytePos((self.to_usize() - rhs.to_usize()) as u32) |
| } |
| } |
| |
| impl Encodable for BytePos { |
| fn encode<S: Encoder>(&self, s: &mut S) -> Result<(), S::Error> { |
| s.emit_u32(self.0) |
| } |
| } |
| |
| impl Decodable for BytePos { |
| fn decode<D: Decoder>(d: &mut D) -> Result<BytePos, D::Error> { |
| Ok(BytePos(d.read_u32()?)) |
| } |
| } |
| |
| impl Pos for CharPos { |
| fn from_usize(n: usize) -> CharPos { CharPos(n) } |
| fn to_usize(&self) -> usize { let CharPos(n) = *self; n } |
| } |
| |
| impl Add for CharPos { |
| type Output = CharPos; |
| |
| fn add(self, rhs: CharPos) -> CharPos { |
| CharPos(self.to_usize() + rhs.to_usize()) |
| } |
| } |
| |
| impl Sub for CharPos { |
| type Output = CharPos; |
| |
| fn sub(self, rhs: CharPos) -> CharPos { |
| CharPos(self.to_usize() - rhs.to_usize()) |
| } |
| } |
| |
| // _____________________________________________________________________________ |
| // Loc, LocWithOpt, FileMapAndLine, FileMapAndBytePos |
| // |
| |
| /// A source code location used for error reporting |
| #[derive(Debug, Clone)] |
| pub struct Loc { |
| /// Information about the original source |
| pub file: Rc<FileMap>, |
| /// The (1-based) line number |
| pub line: usize, |
| /// The (0-based) column offset |
| pub col: CharPos, |
| /// The (0-based) column offset when displayed |
| pub col_display: usize, |
| } |
| |
| /// A source code location used as the result of lookup_char_pos_adj |
| // Actually, *none* of the clients use the filename *or* file field; |
| // perhaps they should just be removed. |
| #[derive(Debug)] |
| pub struct LocWithOpt { |
| pub filename: FileName, |
| pub line: usize, |
| pub col: CharPos, |
| pub file: Option<Rc<FileMap>>, |
| } |
| |
| // used to be structural records. Better names, anyone? |
| #[derive(Debug)] |
| pub struct FileMapAndLine { pub fm: Rc<FileMap>, pub line: usize } |
| #[derive(Debug)] |
| pub struct FileMapAndBytePos { pub fm: Rc<FileMap>, pub pos: BytePos } |
| |
| #[derive(Copy, Clone, Debug, PartialEq, Eq)] |
| pub struct LineInfo { |
| /// Index of line, starting from 0. |
| pub line_index: usize, |
| |
| /// Column in line where span begins, starting from 0. |
| pub start_col: CharPos, |
| |
| /// Column in line where span ends, starting from 0, exclusive. |
| pub end_col: CharPos, |
| } |
| |
| pub struct FileLines { |
| pub file: Rc<FileMap>, |
| pub lines: Vec<LineInfo> |
| } |
| |
| thread_local!(pub static SPAN_DEBUG: Cell<fn(Span, &mut fmt::Formatter) -> fmt::Result> = |
| Cell::new(default_span_debug)); |
| |
| #[derive(Debug)] |
| pub struct MacroBacktrace { |
| /// span where macro was applied to generate this code |
| pub call_site: Span, |
| |
| /// name of macro that was applied (e.g., "foo!" or "#[derive(Eq)]") |
| pub macro_decl_name: String, |
| |
| /// span where macro was defined (if known) |
| pub def_site_span: Option<Span>, |
| } |
| |
| // _____________________________________________________________________________ |
| // SpanLinesError, SpanSnippetError, DistinctSources, MalformedCodemapPositions |
| // |
| |
| pub type FileLinesResult = Result<FileLines, SpanLinesError>; |
| |
| #[derive(Clone, PartialEq, Eq, Debug)] |
| pub enum SpanLinesError { |
| IllFormedSpan(Span), |
| DistinctSources(DistinctSources), |
| } |
| |
| #[derive(Clone, PartialEq, Eq, Debug)] |
| pub enum SpanSnippetError { |
| IllFormedSpan(Span), |
| DistinctSources(DistinctSources), |
| MalformedForCodemap(MalformedCodemapPositions), |
| SourceNotAvailable { filename: FileName } |
| } |
| |
| #[derive(Clone, PartialEq, Eq, Debug)] |
| pub struct DistinctSources { |
| pub begin: (FileName, BytePos), |
| pub end: (FileName, BytePos) |
| } |
| |
| #[derive(Clone, PartialEq, Eq, Debug)] |
| pub struct MalformedCodemapPositions { |
| pub name: FileName, |
| pub source_len: usize, |
| pub begin_pos: BytePos, |
| pub end_pos: BytePos |
| } |
| |
| // Given a slice of line start positions and a position, returns the index of |
| // the line the position is on. Returns -1 if the position is located before |
| // the first line. |
| fn lookup_line(lines: &[BytePos], pos: BytePos) -> isize { |
| match lines.binary_search(&pos) { |
| Ok(line) => line as isize, |
| Err(line) => line as isize - 1 |
| } |
| } |
| |
| #[cfg(test)] |
| mod tests { |
| use super::{lookup_line, BytePos}; |
| |
| #[test] |
| fn test_lookup_line() { |
| |
| let lines = &[BytePos(3), BytePos(17), BytePos(28)]; |
| |
| assert_eq!(lookup_line(lines, BytePos(0)), -1); |
| assert_eq!(lookup_line(lines, BytePos(3)), 0); |
| assert_eq!(lookup_line(lines, BytePos(4)), 0); |
| |
| assert_eq!(lookup_line(lines, BytePos(16)), 0); |
| assert_eq!(lookup_line(lines, BytePos(17)), 1); |
| assert_eq!(lookup_line(lines, BytePos(18)), 1); |
| |
| assert_eq!(lookup_line(lines, BytePos(28)), 2); |
| assert_eq!(lookup_line(lines, BytePos(29)), 2); |
| } |
| } |