// Copyright 2012-2014 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 or the MIT license // , at your // option. This file may not be copied, modified, or distributed // except according to those terms. pub use self::AnnNode::*; use rustc_target::spec::abi::{self, Abi}; use ast::{self, BlockCheckMode, PatKind, RangeEnd, RangeSyntax}; use ast::{SelfKind, GenericBound, TraitBoundModifier}; use ast::{Attribute, MacDelimiter, GenericArg}; use util::parser::{self, AssocOp, Fixity}; use attr; use codemap::{self, CodeMap, Spanned}; use syntax_pos::{self, BytePos}; use syntax_pos::hygiene::{Mark, SyntaxContext}; use parse::token::{self, BinOpToken, Token}; use parse::lexer::comments; use parse::{self, ParseSess}; use print::pp::{self, Breaks}; use print::pp::Breaks::{Consistent, Inconsistent}; use ptr::P; use std_inject; use symbol::keywords; use syntax_pos::{DUMMY_SP, FileName}; use tokenstream::{self, TokenStream, TokenTree}; use std::ascii; use std::io::{self, Write, Read}; use std::iter::{self, Peekable}; use std::vec; pub enum AnnNode<'a> { NodeIdent(&'a ast::Ident), NodeName(&'a ast::Name), NodeBlock(&'a ast::Block), NodeItem(&'a ast::Item), NodeSubItem(ast::NodeId), NodeExpr(&'a ast::Expr), NodePat(&'a ast::Pat), } pub trait PpAnn { fn pre(&self, _state: &mut State, _node: AnnNode) -> io::Result<()> { Ok(()) } fn post(&self, _state: &mut State, _node: AnnNode) -> io::Result<()> { Ok(()) } } #[derive(Copy, Clone)] pub struct NoAnn; impl PpAnn for NoAnn {} pub struct State<'a> { pub s: pp::Printer<'a>, cm: Option<&'a CodeMap>, comments: Option >, literals: Peekable>, cur_cmnt: usize, boxes: Vec, ann: &'a (dyn PpAnn+'a), } fn rust_printer<'a>(writer: Box, ann: &'a dyn PpAnn) -> State<'a> { State { s: pp::mk_printer(writer, DEFAULT_COLUMNS), cm: None, comments: None, literals: vec![].into_iter().peekable(), cur_cmnt: 0, boxes: Vec::new(), ann, } } pub const INDENT_UNIT: usize = 4; pub const DEFAULT_COLUMNS: usize = 78; /// Requires you to pass an input filename and reader so that /// it can scan the input text for comments and literals to /// copy forward. pub fn print_crate<'a>(cm: &'a CodeMap, sess: &ParseSess, krate: &ast::Crate, filename: FileName, input: &mut dyn Read, out: Box, ann: &'a dyn PpAnn, is_expanded: bool) -> io::Result<()> { let mut s = State::new_from_input(cm, sess, filename, input, out, ann, is_expanded); if is_expanded && std_inject::injected_crate_name().is_some() { // We need to print `#![no_std]` (and its feature gate) so that // compiling pretty-printed source won't inject libstd again. // However we don't want these attributes in the AST because // of the feature gate, so we fake them up here. // #![feature(prelude_import)] let pi_nested = attr::mk_nested_word_item(ast::Ident::from_str("prelude_import")); let list = attr::mk_list_item(DUMMY_SP, ast::Ident::from_str("feature"), vec![pi_nested]); let fake_attr = attr::mk_attr_inner(DUMMY_SP, attr::mk_attr_id(), list); s.print_attribute(&fake_attr)?; // #![no_std] let no_std_meta = attr::mk_word_item(ast::Ident::from_str("no_std")); let fake_attr = attr::mk_attr_inner(DUMMY_SP, attr::mk_attr_id(), no_std_meta); s.print_attribute(&fake_attr)?; } s.print_mod(&krate.module, &krate.attrs)?; s.print_remaining_comments()?; s.s.eof() } impl<'a> State<'a> { pub fn new_from_input(cm: &'a CodeMap, sess: &ParseSess, filename: FileName, input: &mut dyn Read, out: Box, ann: &'a dyn PpAnn, is_expanded: bool) -> State<'a> { let (cmnts, lits) = comments::gather_comments_and_literals(sess, filename, input); State::new( cm, out, ann, Some(cmnts), // If the code is post expansion, don't use the table of // literals, since it doesn't correspond with the literals // in the AST anymore. if is_expanded { None } else { Some(lits) }) } pub fn new(cm: &'a CodeMap, out: Box, ann: &'a dyn PpAnn, comments: Option>, literals: Option>) -> State<'a> { State { s: pp::mk_printer(out, DEFAULT_COLUMNS), cm: Some(cm), comments, literals: literals.unwrap_or_default().into_iter().peekable(), cur_cmnt: 0, boxes: Vec::new(), ann, } } } pub fn to_string(f: F) -> String where F: FnOnce(&mut State) -> io::Result<()>, { let mut wr = Vec::new(); { let ann = NoAnn; let mut printer = rust_printer(Box::new(&mut wr), &ann); f(&mut printer).unwrap(); printer.s.eof().unwrap(); } String::from_utf8(wr).unwrap() } fn binop_to_string(op: BinOpToken) -> &'static str { match op { token::Plus => "+", token::Minus => "-", token::Star => "*", token::Slash => "/", token::Percent => "%", token::Caret => "^", token::And => "&", token::Or => "|", token::Shl => "<<", token::Shr => ">>", } } pub fn token_to_string(tok: &Token) -> String { match *tok { token::Eq => "=".to_string(), token::Lt => "<".to_string(), token::Le => "<=".to_string(), token::EqEq => "==".to_string(), token::Ne => "!=".to_string(), token::Ge => ">=".to_string(), token::Gt => ">".to_string(), token::Not => "!".to_string(), token::Tilde => "~".to_string(), token::OrOr => "||".to_string(), token::AndAnd => "&&".to_string(), token::BinOp(op) => binop_to_string(op).to_string(), token::BinOpEq(op) => format!("{}=", binop_to_string(op)), /* Structural symbols */ token::At => "@".to_string(), token::Dot => ".".to_string(), token::DotDot => "..".to_string(), token::DotDotDot => "...".to_string(), token::DotDotEq => "..=".to_string(), token::DotEq => ".=".to_string(), token::Comma => ",".to_string(), token::Semi => ";".to_string(), token::Colon => ":".to_string(), token::ModSep => "::".to_string(), token::RArrow => "->".to_string(), token::LArrow => "<-".to_string(), token::FatArrow => "=>".to_string(), token::OpenDelim(token::Paren) => "(".to_string(), token::CloseDelim(token::Paren) => ")".to_string(), token::OpenDelim(token::Bracket) => "[".to_string(), token::CloseDelim(token::Bracket) => "]".to_string(), token::OpenDelim(token::Brace) => "{".to_string(), token::CloseDelim(token::Brace) => "}".to_string(), token::OpenDelim(token::NoDelim) | token::CloseDelim(token::NoDelim) => " ".to_string(), token::Pound => "#".to_string(), token::Dollar => "$".to_string(), token::Question => "?".to_string(), token::SingleQuote => "'".to_string(), /* Literals */ token::Literal(lit, suf) => { let mut out = match lit { token::Byte(b) => format!("b'{}'", b), token::Char(c) => format!("'{}'", c), token::Float(c) | token::Integer(c) => c.to_string(), token::Str_(s) => format!("\"{}\"", s), token::StrRaw(s, n) => format!("r{delim}\"{string}\"{delim}", delim=repeat("#", n as usize), string=s), token::ByteStr(v) => format!("b\"{}\"", v), token::ByteStrRaw(s, n) => format!("br{delim}\"{string}\"{delim}", delim=repeat("#", n as usize), string=s), }; if let Some(s) = suf { out.push_str(&s.as_str()) } out } /* Name components */ token::Ident(s, false) => s.to_string(), token::Ident(s, true) => format!("r#{}", s), token::Lifetime(s) => s.to_string(), /* Other */ token::DocComment(s) => s.to_string(), token::Eof => "".to_string(), token::Whitespace => " ".to_string(), token::Comment => "/* */".to_string(), token::Shebang(s) => format!("/* shebang: {}*/", s), token::Interpolated(ref nt) => match nt.0 { token::NtExpr(ref e) => expr_to_string(e), token::NtMeta(ref e) => meta_item_to_string(e), token::NtTy(ref e) => ty_to_string(e), token::NtPath(ref e) => path_to_string(e), token::NtItem(ref e) => item_to_string(e), token::NtBlock(ref e) => block_to_string(e), token::NtStmt(ref e) => stmt_to_string(e), token::NtPat(ref e) => pat_to_string(e), token::NtIdent(e, false) => ident_to_string(e), token::NtIdent(e, true) => format!("r#{}", ident_to_string(e)), token::NtLifetime(e) => ident_to_string(e), token::NtLiteral(ref e) => expr_to_string(e), token::NtTT(ref tree) => tt_to_string(tree.clone()), token::NtArm(ref e) => arm_to_string(e), token::NtImplItem(ref e) => impl_item_to_string(e), token::NtTraitItem(ref e) => trait_item_to_string(e), token::NtGenerics(ref e) => generic_params_to_string(&e.params), token::NtWhereClause(ref e) => where_clause_to_string(e), token::NtArg(ref e) => arg_to_string(e), token::NtVis(ref e) => vis_to_string(e), token::NtForeignItem(ref e) => foreign_item_to_string(e), } } } pub fn ty_to_string(ty: &ast::Ty) -> String { to_string(|s| s.print_type(ty)) } pub fn bounds_to_string(bounds: &[ast::GenericBound]) -> String { to_string(|s| s.print_type_bounds("", bounds)) } pub fn pat_to_string(pat: &ast::Pat) -> String { to_string(|s| s.print_pat(pat)) } pub fn arm_to_string(arm: &ast::Arm) -> String { to_string(|s| s.print_arm(arm)) } pub fn expr_to_string(e: &ast::Expr) -> String { to_string(|s| s.print_expr(e)) } pub fn lifetime_to_string(lt: &ast::Lifetime) -> String { to_string(|s| s.print_lifetime(*lt)) } pub fn tt_to_string(tt: tokenstream::TokenTree) -> String { to_string(|s| s.print_tt(tt)) } pub fn tts_to_string(tts: &[tokenstream::TokenTree]) -> String { to_string(|s| s.print_tts(tts.iter().cloned().collect())) } pub fn tokens_to_string(tokens: TokenStream) -> String { to_string(|s| s.print_tts(tokens)) } pub fn stmt_to_string(stmt: &ast::Stmt) -> String { to_string(|s| s.print_stmt(stmt)) } pub fn attr_to_string(attr: &ast::Attribute) -> String { to_string(|s| s.print_attribute(attr)) } pub fn item_to_string(i: &ast::Item) -> String { to_string(|s| s.print_item(i)) } pub fn impl_item_to_string(i: &ast::ImplItem) -> String { to_string(|s| s.print_impl_item(i)) } pub fn trait_item_to_string(i: &ast::TraitItem) -> String { to_string(|s| s.print_trait_item(i)) } pub fn generic_params_to_string(generic_params: &[ast::GenericParam]) -> String { to_string(|s| s.print_generic_params(generic_params)) } pub fn where_clause_to_string(i: &ast::WhereClause) -> String { to_string(|s| s.print_where_clause(i)) } pub fn fn_block_to_string(p: &ast::FnDecl) -> String { to_string(|s| s.print_fn_block_args(p)) } pub fn path_to_string(p: &ast::Path) -> String { to_string(|s| s.print_path(p, false, 0)) } pub fn path_segment_to_string(p: &ast::PathSegment) -> String { to_string(|s| s.print_path_segment(p, false)) } pub fn ident_to_string(id: ast::Ident) -> String { to_string(|s| s.print_ident(id)) } pub fn vis_to_string(v: &ast::Visibility) -> String { to_string(|s| s.print_visibility(v)) } pub fn fun_to_string(decl: &ast::FnDecl, header: ast::FnHeader, name: ast::Ident, generics: &ast::Generics) -> String { to_string(|s| { s.head("")?; s.print_fn(decl, header, Some(name), generics, &codemap::dummy_spanned(ast::VisibilityKind::Inherited))?; s.end()?; // Close the head box s.end() // Close the outer box }) } pub fn block_to_string(blk: &ast::Block) -> String { to_string(|s| { // containing cbox, will be closed by print-block at } s.cbox(INDENT_UNIT)?; // head-ibox, will be closed by print-block after { s.ibox(0)?; s.print_block(blk) }) } pub fn meta_list_item_to_string(li: &ast::NestedMetaItem) -> String { to_string(|s| s.print_meta_list_item(li)) } pub fn meta_item_to_string(mi: &ast::MetaItem) -> String { to_string(|s| s.print_meta_item(mi)) } pub fn attribute_to_string(attr: &ast::Attribute) -> String { to_string(|s| s.print_attribute(attr)) } pub fn lit_to_string(l: &ast::Lit) -> String { to_string(|s| s.print_literal(l)) } pub fn variant_to_string(var: &ast::Variant) -> String { to_string(|s| s.print_variant(var)) } pub fn arg_to_string(arg: &ast::Arg) -> String { to_string(|s| s.print_arg(arg, false)) } pub fn mac_to_string(arg: &ast::Mac) -> String { to_string(|s| s.print_mac(arg)) } pub fn foreign_item_to_string(arg: &ast::ForeignItem) -> String { to_string(|s| s.print_foreign_item(arg)) } pub fn visibility_qualified(vis: &ast::Visibility, s: &str) -> String { format!("{}{}", to_string(|s| s.print_visibility(vis)), s) } pub trait PrintState<'a> { fn writer(&mut self) -> &mut pp::Printer<'a>; fn boxes(&mut self) -> &mut Vec; fn comments(&mut self) -> &mut Option>; fn cur_cmnt(&mut self) -> &mut usize; fn cur_lit(&mut self) -> Option<&comments::Literal>; fn bump_lit(&mut self) -> Option; fn word_space(&mut self, w: &str) -> io::Result<()> { self.writer().word(w)?; self.writer().space() } fn popen(&mut self) -> io::Result<()> { self.writer().word("(") } fn pclose(&mut self) -> io::Result<()> { self.writer().word(")") } fn is_begin(&mut self) -> bool { match self.writer().last_token() { pp::Token::Begin(_) => true, _ => false, } } fn is_end(&mut self) -> bool { match self.writer().last_token() { pp::Token::End => true, _ => false, } } // is this the beginning of a line? fn is_bol(&mut self) -> bool { self.writer().last_token().is_eof() || self.writer().last_token().is_hardbreak_tok() } fn hardbreak_if_not_bol(&mut self) -> io::Result<()> { if !self.is_bol() { self.writer().hardbreak()? } Ok(()) } // "raw box" fn rbox(&mut self, u: usize, b: pp::Breaks) -> io::Result<()> { self.boxes().push(b); self.writer().rbox(u, b) } fn ibox(&mut self, u: usize) -> io::Result<()> { self.boxes().push(pp::Breaks::Inconsistent); self.writer().ibox(u) } fn end(&mut self) -> io::Result<()> { self.boxes().pop().unwrap(); self.writer().end() } fn commasep(&mut self, b: Breaks, elts: &[T], mut op: F) -> io::Result<()> where F: FnMut(&mut Self, &T) -> io::Result<()>, { self.rbox(0, b)?; let mut first = true; for elt in elts { if first { first = false; } else { self.word_space(",")?; } op(self, elt)?; } self.end() } fn next_lit(&mut self, pos: BytePos) -> Option { while let Some(ltrl) = self.cur_lit().cloned() { if ltrl.pos > pos { break; } // we don't need the value here since we're forced to clone cur_lit // due to lack of NLL. self.bump_lit(); if ltrl.pos == pos { return Some(ltrl); } } None } fn maybe_print_comment(&mut self, pos: BytePos) -> io::Result<()> { while let Some(ref cmnt) = self.next_comment() { if cmnt.pos < pos { self.print_comment(cmnt)?; } else { break } } Ok(()) } fn print_comment(&mut self, cmnt: &comments::Comment) -> io::Result<()> { let r = match cmnt.style { comments::Mixed => { assert_eq!(cmnt.lines.len(), 1); self.writer().zerobreak()?; self.writer().word(&cmnt.lines[0])?; self.writer().zerobreak() } comments::Isolated => { self.hardbreak_if_not_bol()?; for line in &cmnt.lines { // Don't print empty lines because they will end up as trailing // whitespace if !line.is_empty() { self.writer().word(&line[..])?; } self.writer().hardbreak()?; } Ok(()) } comments::Trailing => { if !self.is_bol() { self.writer().word(" ")?; } if cmnt.lines.len() == 1 { self.writer().word(&cmnt.lines[0])?; self.writer().hardbreak() } else { self.ibox(0)?; for line in &cmnt.lines { if !line.is_empty() { self.writer().word(&line[..])?; } self.writer().hardbreak()?; } self.end() } } comments::BlankLine => { // We need to do at least one, possibly two hardbreaks. let is_semi = match self.writer().last_token() { pp::Token::String(s, _) => ";" == s, _ => false }; if is_semi || self.is_begin() || self.is_end() { self.writer().hardbreak()?; } self.writer().hardbreak() } }; match r { Ok(()) => { *self.cur_cmnt() = *self.cur_cmnt() + 1; Ok(()) } Err(e) => Err(e), } } fn next_comment(&mut self) -> Option { let cur_cmnt = *self.cur_cmnt(); match *self.comments() { Some(ref cmnts) => { if cur_cmnt < cmnts.len() { Some(cmnts[cur_cmnt].clone()) } else { None } } _ => None } } fn print_literal(&mut self, lit: &ast::Lit) -> io::Result<()> { self.maybe_print_comment(lit.span.lo())?; if let Some(ltrl) = self.next_lit(lit.span.lo()) { return self.writer().word(<rl.lit); } match lit.node { ast::LitKind::Str(st, style) => self.print_string(&st.as_str(), style), ast::LitKind::Byte(byte) => { let mut res = String::from("b'"); res.extend(ascii::escape_default(byte).map(|c| c as char)); res.push('\''); self.writer().word(&res[..]) } ast::LitKind::Char(ch) => { let mut res = String::from("'"); res.extend(ch.escape_default()); res.push('\''); self.writer().word(&res[..]) } ast::LitKind::Int(i, t) => { match t { ast::LitIntType::Signed(st) => { self.writer().word(&st.val_to_string(i as i128)) } ast::LitIntType::Unsigned(ut) => { self.writer().word(&ut.val_to_string(i)) } ast::LitIntType::Unsuffixed => { self.writer().word(&format!("{}", i)) } } } ast::LitKind::Float(ref f, t) => { self.writer().word(&format!("{}{}", &f, t.ty_to_string())) } ast::LitKind::FloatUnsuffixed(ref f) => self.writer().word(&f.as_str()), ast::LitKind::Bool(val) => { if val { self.writer().word("true") } else { self.writer().word("false") } } ast::LitKind::ByteStr(ref v) => { let mut escaped: String = String::new(); for &ch in v.iter() { escaped.extend(ascii::escape_default(ch) .map(|c| c as char)); } self.writer().word(&format!("b\"{}\"", escaped)) } } } fn print_string(&mut self, st: &str, style: ast::StrStyle) -> io::Result<()> { let st = match style { ast::StrStyle::Cooked => { (format!("\"{}\"", st.escape_debug())) } ast::StrStyle::Raw(n) => { (format!("r{delim}\"{string}\"{delim}", delim=repeat("#", n as usize), string=st)) } }; self.writer().word(&st[..]) } fn print_inner_attributes(&mut self, attrs: &[ast::Attribute]) -> io::Result<()> { self.print_either_attributes(attrs, ast::AttrStyle::Inner, false, true) } fn print_inner_attributes_no_trailing_hardbreak(&mut self, attrs: &[ast::Attribute]) -> io::Result<()> { self.print_either_attributes(attrs, ast::AttrStyle::Inner, false, false) } fn print_outer_attributes(&mut self, attrs: &[ast::Attribute]) -> io::Result<()> { self.print_either_attributes(attrs, ast::AttrStyle::Outer, false, true) } fn print_inner_attributes_inline(&mut self, attrs: &[ast::Attribute]) -> io::Result<()> { self.print_either_attributes(attrs, ast::AttrStyle::Inner, true, true) } fn print_outer_attributes_inline(&mut self, attrs: &[ast::Attribute]) -> io::Result<()> { self.print_either_attributes(attrs, ast::AttrStyle::Outer, true, true) } fn print_either_attributes(&mut self, attrs: &[ast::Attribute], kind: ast::AttrStyle, is_inline: bool, trailing_hardbreak: bool) -> io::Result<()> { let mut count = 0; for attr in attrs { if attr.style == kind { self.print_attribute_inline(attr, is_inline)?; if is_inline { self.nbsp()?; } count += 1; } } if count > 0 && trailing_hardbreak && !is_inline { self.hardbreak_if_not_bol()?; } Ok(()) } fn print_attribute_path(&mut self, path: &ast::Path) -> io::Result<()> { for (i, segment) in path.segments.iter().enumerate() { if i > 0 { self.writer().word("::")? } if segment.ident.name != keywords::CrateRoot.name() && segment.ident.name != keywords::DollarCrate.name() { self.writer().word(&segment.ident.as_str())?; } else if segment.ident.name == keywords::DollarCrate.name() { self.print_dollar_crate(segment.ident.span.ctxt())?; } } Ok(()) } fn print_attribute(&mut self, attr: &ast::Attribute) -> io::Result<()> { self.print_attribute_inline(attr, false) } fn print_attribute_inline(&mut self, attr: &ast::Attribute, is_inline: bool) -> io::Result<()> { if !is_inline { self.hardbreak_if_not_bol()?; } self.maybe_print_comment(attr.span.lo())?; if attr.is_sugared_doc { self.writer().word(&attr.value_str().unwrap().as_str())?; self.writer().hardbreak() } else { match attr.style { ast::AttrStyle::Inner => self.writer().word("#![")?, ast::AttrStyle::Outer => self.writer().word("#[")?, } if let Some(mi) = attr.meta() { self.print_meta_item(&mi)? } else { self.print_attribute_path(&attr.path)?; self.writer().space()?; self.print_tts(attr.tokens.clone())?; } self.writer().word("]") } } fn print_meta_list_item(&mut self, item: &ast::NestedMetaItem) -> io::Result<()> { match item.node { ast::NestedMetaItemKind::MetaItem(ref mi) => { self.print_meta_item(mi) }, ast::NestedMetaItemKind::Literal(ref lit) => { self.print_literal(lit) } } } fn print_meta_item(&mut self, item: &ast::MetaItem) -> io::Result<()> { self.ibox(INDENT_UNIT)?; match item.node { ast::MetaItemKind::Word => self.print_attribute_path(&item.ident)?, ast::MetaItemKind::NameValue(ref value) => { self.print_attribute_path(&item.ident)?; self.writer().space()?; self.word_space("=")?; self.print_literal(value)?; } ast::MetaItemKind::List(ref items) => { self.print_attribute_path(&item.ident)?; self.popen()?; self.commasep(Consistent, &items[..], |s, i| s.print_meta_list_item(i))?; self.pclose()?; } } self.end() } /// This doesn't deserve to be called "pretty" printing, but it should be /// meaning-preserving. A quick hack that might help would be to look at the /// spans embedded in the TTs to decide where to put spaces and newlines. /// But it'd be better to parse these according to the grammar of the /// appropriate macro, transcribe back into the grammar we just parsed from, /// and then pretty-print the resulting AST nodes (so, e.g., we print /// expression arguments as expressions). It can be done! I think. fn print_tt(&mut self, tt: tokenstream::TokenTree) -> io::Result<()> { match tt { TokenTree::Token(_, ref tk) => { self.writer().word(&token_to_string(tk))?; match *tk { parse::token::DocComment(..) => { self.writer().hardbreak() } _ => Ok(()) } } TokenTree::Delimited(_, ref delimed) => { self.writer().word(&token_to_string(&delimed.open_token()))?; self.writer().space()?; self.print_tts(delimed.stream())?; self.writer().space()?; self.writer().word(&token_to_string(&delimed.close_token())) }, } } fn print_tts(&mut self, tts: tokenstream::TokenStream) -> io::Result<()> { self.ibox(0)?; for (i, tt) in tts.into_trees().enumerate() { if i != 0 { self.writer().space()?; } self.print_tt(tt)?; } self.end() } fn space_if_not_bol(&mut self) -> io::Result<()> { if !self.is_bol() { self.writer().space()?; } Ok(()) } fn nbsp(&mut self) -> io::Result<()> { self.writer().word(" ") } fn print_dollar_crate(&mut self, mut ctxt: SyntaxContext) -> io::Result<()> { if let Some(mark) = ctxt.adjust(Mark::root()) { // Make a best effort to print something that complies if mark.is_builtin() { if let Some(name) = std_inject::injected_crate_name() { self.writer().word("::")?; self.writer().word(name)?; } } } Ok(()) } } impl<'a> PrintState<'a> for State<'a> { fn writer(&mut self) -> &mut pp::Printer<'a> { &mut self.s } fn boxes(&mut self) -> &mut Vec { &mut self.boxes } fn comments(&mut self) -> &mut Option> { &mut self.comments } fn cur_cmnt(&mut self) -> &mut usize { &mut self.cur_cmnt } fn cur_lit(&mut self) -> Option<&comments::Literal> { self.literals.peek() } fn bump_lit(&mut self) -> Option { self.literals.next() } } impl<'a> State<'a> { pub fn cbox(&mut self, u: usize) -> io::Result<()> { self.boxes.push(pp::Breaks::Consistent); self.s.cbox(u) } pub fn word_nbsp(&mut self, w: &str) -> io::Result<()> { self.s.word(w)?; self.nbsp() } pub fn head(&mut self, w: &str) -> io::Result<()> { // outer-box is consistent self.cbox(INDENT_UNIT)?; // head-box is inconsistent self.ibox(w.len() + 1)?; // keyword that starts the head if !w.is_empty() { self.word_nbsp(w)?; } Ok(()) } pub fn bopen(&mut self) -> io::Result<()> { self.s.word("{")?; self.end() // close the head-box } pub fn bclose_(&mut self, span: syntax_pos::Span, indented: usize) -> io::Result<()> { self.bclose_maybe_open(span, indented, true) } pub fn bclose_maybe_open(&mut self, span: syntax_pos::Span, indented: usize, close_box: bool) -> io::Result<()> { self.maybe_print_comment(span.hi())?; self.break_offset_if_not_bol(1, -(indented as isize))?; self.s.word("}")?; if close_box { self.end()?; // close the outer-box } Ok(()) } pub fn bclose(&mut self, span: syntax_pos::Span) -> io::Result<()> { self.bclose_(span, INDENT_UNIT) } pub fn in_cbox(&self) -> bool { match self.boxes.last() { Some(&last_box) => last_box == pp::Breaks::Consistent, None => false } } pub fn break_offset_if_not_bol(&mut self, n: usize, off: isize) -> io::Result<()> { if !self.is_bol() { self.s.break_offset(n, off) } else { if off != 0 && self.s.last_token().is_hardbreak_tok() { // We do something pretty sketchy here: tuck the nonzero // offset-adjustment we were going to deposit along with the // break into the previous hardbreak. self.s.replace_last_token(pp::Printer::hardbreak_tok_offset(off)); } Ok(()) } } // Synthesizes a comment that was not textually present in the original source // file. pub fn synth_comment(&mut self, text: String) -> io::Result<()> { self.s.word("/*")?; self.s.space()?; self.s.word(&text[..])?; self.s.space()?; self.s.word("*/") } pub fn commasep_cmnt(&mut self, b: Breaks, elts: &[T], mut op: F, mut get_span: G) -> io::Result<()> where F: FnMut(&mut State, &T) -> io::Result<()>, G: FnMut(&T) -> syntax_pos::Span, { self.rbox(0, b)?; let len = elts.len(); let mut i = 0; for elt in elts { self.maybe_print_comment(get_span(elt).hi())?; op(self, elt)?; i += 1; if i < len { self.s.word(",")?; self.maybe_print_trailing_comment(get_span(elt), Some(get_span(&elts[i]).hi()))?; self.space_if_not_bol()?; } } self.end() } pub fn commasep_exprs(&mut self, b: Breaks, exprs: &[P]) -> io::Result<()> { self.commasep_cmnt(b, exprs, |s, e| s.print_expr(e), |e| e.span) } pub fn print_mod(&mut self, _mod: &ast::Mod, attrs: &[ast::Attribute]) -> io::Result<()> { self.print_inner_attributes(attrs)?; for item in &_mod.items { self.print_item(item)?; } Ok(()) } pub fn print_foreign_mod(&mut self, nmod: &ast::ForeignMod, attrs: &[ast::Attribute]) -> io::Result<()> { self.print_inner_attributes(attrs)?; for item in &nmod.items { self.print_foreign_item(item)?; } Ok(()) } pub fn print_opt_lifetime(&mut self, lifetime: &Option) -> io::Result<()> { if let Some(lt) = *lifetime { self.print_lifetime(lt)?; self.nbsp()?; } Ok(()) } pub fn print_generic_arg(&mut self, generic_arg: &GenericArg) -> io::Result<()> { match generic_arg { GenericArg::Lifetime(lt) => self.print_lifetime(*lt), GenericArg::Type(ty) => self.print_type(ty), } } pub fn print_type(&mut self, ty: &ast::Ty) -> io::Result<()> { self.maybe_print_comment(ty.span.lo())?; self.ibox(0)?; match ty.node { ast::TyKind::Slice(ref ty) => { self.s.word("[")?; self.print_type(ty)?; self.s.word("]")?; } ast::TyKind::Ptr(ref mt) => { self.s.word("*")?; match mt.mutbl { ast::Mutability::Mutable => self.word_nbsp("mut")?, ast::Mutability::Immutable => self.word_nbsp("const")?, } self.print_type(&mt.ty)?; } ast::TyKind::Rptr(ref lifetime, ref mt) => { self.s.word("&")?; self.print_opt_lifetime(lifetime)?; self.print_mt(mt)?; } ast::TyKind::Never => { self.s.word("!")?; }, ast::TyKind::Tup(ref elts) => { self.popen()?; self.commasep(Inconsistent, &elts[..], |s, ty| s.print_type(ty))?; if elts.len() == 1 { self.s.word(",")?; } self.pclose()?; } ast::TyKind::Paren(ref typ) => { self.popen()?; self.print_type(typ)?; self.pclose()?; } ast::TyKind::BareFn(ref f) => { self.print_ty_fn(f.abi, f.unsafety, &f.decl, None, &f.generic_params)?; } ast::TyKind::Path(None, ref path) => { self.print_path(path, false, 0)?; } ast::TyKind::Path(Some(ref qself), ref path) => { self.print_qpath(path, qself, false)? } ast::TyKind::TraitObject(ref bounds, syntax) => { let prefix = if syntax == ast::TraitObjectSyntax::Dyn { "dyn" } else { "" }; self.print_type_bounds(prefix, &bounds[..])?; } ast::TyKind::ImplTrait(_, ref bounds) => { self.print_type_bounds("impl", &bounds[..])?; } ast::TyKind::Array(ref ty, ref length) => { self.s.word("[")?; self.print_type(ty)?; self.s.word("; ")?; self.print_expr(&length.value)?; self.s.word("]")?; } ast::TyKind::Typeof(ref e) => { self.s.word("typeof(")?; self.print_expr(&e.value)?; self.s.word(")")?; } ast::TyKind::Infer => { self.s.word("_")?; } ast::TyKind::Err => { self.s.word("?")?; } ast::TyKind::ImplicitSelf => { self.s.word("Self")?; } ast::TyKind::Mac(ref m) => { self.print_mac(m)?; } } self.end() } pub fn print_foreign_item(&mut self, item: &ast::ForeignItem) -> io::Result<()> { self.hardbreak_if_not_bol()?; self.maybe_print_comment(item.span.lo())?; self.print_outer_attributes(&item.attrs)?; match item.node { ast::ForeignItemKind::Fn(ref decl, ref generics) => { self.head("")?; self.print_fn(decl, ast::FnHeader::default(), Some(item.ident), generics, &item.vis)?; self.end()?; // end head-ibox self.s.word(";")?; self.end() // end the outer fn box } ast::ForeignItemKind::Static(ref t, m) => { self.head(&visibility_qualified(&item.vis, "static"))?; if m { self.word_space("mut")?; } self.print_ident(item.ident)?; self.word_space(":")?; self.print_type(t)?; self.s.word(";")?; self.end()?; // end the head-ibox self.end() // end the outer cbox } ast::ForeignItemKind::Ty => { self.head(&visibility_qualified(&item.vis, "type"))?; self.print_ident(item.ident)?; self.s.word(";")?; self.end()?; // end the head-ibox self.end() // end the outer cbox } ast::ForeignItemKind::Macro(ref m) => { self.print_mac(m)?; match m.node.delim { MacDelimiter::Brace => Ok(()), _ => self.s.word(";") } } } } fn print_associated_const(&mut self, ident: ast::Ident, ty: &ast::Ty, default: Option<&ast::Expr>, vis: &ast::Visibility) -> io::Result<()> { self.s.word(&visibility_qualified(vis, ""))?; self.word_space("const")?; self.print_ident(ident)?; self.word_space(":")?; self.print_type(ty)?; if let Some(expr) = default { self.s.space()?; self.word_space("=")?; self.print_expr(expr)?; } self.s.word(";") } fn print_associated_type(&mut self, ident: ast::Ident, bounds: Option<&ast::GenericBounds>, ty: Option<&ast::Ty>) -> io::Result<()> { self.word_space("type")?; self.print_ident(ident)?; if let Some(bounds) = bounds { self.print_type_bounds(":", bounds)?; } if let Some(ty) = ty { self.s.space()?; self.word_space("=")?; self.print_type(ty)?; } self.s.word(";") } /// Pretty-print an item pub fn print_item(&mut self, item: &ast::Item) -> io::Result<()> { self.hardbreak_if_not_bol()?; self.maybe_print_comment(item.span.lo())?; self.print_outer_attributes(&item.attrs)?; self.ann.pre(self, NodeItem(item))?; match item.node { ast::ItemKind::ExternCrate(orig_name) => { self.head(&visibility_qualified(&item.vis, "extern crate"))?; if let Some(orig_name) = orig_name { self.print_name(orig_name)?; self.s.space()?; self.s.word("as")?; self.s.space()?; } self.print_ident(item.ident)?; self.s.word(";")?; self.end()?; // end inner head-block self.end()?; // end outer head-block } ast::ItemKind::Use(ref tree) => { self.head(&visibility_qualified(&item.vis, "use"))?; self.print_use_tree(tree)?; self.s.word(";")?; self.end()?; // end inner head-block self.end()?; // end outer head-block } ast::ItemKind::Static(ref ty, m, ref expr) => { self.head(&visibility_qualified(&item.vis, "static"))?; if m == ast::Mutability::Mutable { self.word_space("mut")?; } self.print_ident(item.ident)?; self.word_space(":")?; self.print_type(ty)?; self.s.space()?; self.end()?; // end the head-ibox self.word_space("=")?; self.print_expr(expr)?; self.s.word(";")?; self.end()?; // end the outer cbox } ast::ItemKind::Const(ref ty, ref expr) => { self.head(&visibility_qualified(&item.vis, "const"))?; self.print_ident(item.ident)?; self.word_space(":")?; self.print_type(ty)?; self.s.space()?; self.end()?; // end the head-ibox self.word_space("=")?; self.print_expr(expr)?; self.s.word(";")?; self.end()?; // end the outer cbox } ast::ItemKind::Fn(ref decl, header, ref typarams, ref body) => { self.head("")?; self.print_fn( decl, header, Some(item.ident), typarams, &item.vis )?; self.s.word(" ")?; self.print_block_with_attrs(body, &item.attrs)?; } ast::ItemKind::Mod(ref _mod) => { self.head(&visibility_qualified(&item.vis, "mod"))?; self.print_ident(item.ident)?; self.nbsp()?; self.bopen()?; self.print_mod(_mod, &item.attrs)?; self.bclose(item.span)?; } ast::ItemKind::ForeignMod(ref nmod) => { self.head("extern")?; self.word_nbsp(&nmod.abi.to_string())?; self.bopen()?; self.print_foreign_mod(nmod, &item.attrs)?; self.bclose(item.span)?; } ast::ItemKind::GlobalAsm(ref ga) => { self.head(&visibility_qualified(&item.vis, "global_asm!"))?; self.s.word(&ga.asm.as_str())?; self.end()?; } ast::ItemKind::Ty(ref ty, ref generics) => { self.ibox(INDENT_UNIT)?; self.ibox(0)?; self.word_nbsp(&visibility_qualified(&item.vis, "type"))?; self.print_ident(item.ident)?; self.print_generic_params(&generics.params)?; self.end()?; // end the inner ibox self.print_where_clause(&generics.where_clause)?; self.s.space()?; self.word_space("=")?; self.print_type(ty)?; self.s.word(";")?; self.end()?; // end the outer ibox } ast::ItemKind::Enum(ref enum_definition, ref params) => { self.print_enum_def( enum_definition, params, item.ident, item.span, &item.vis )?; } ast::ItemKind::Struct(ref struct_def, ref generics) => { self.head(&visibility_qualified(&item.vis, "struct"))?; self.print_struct(struct_def, generics, item.ident, item.span, true)?; } ast::ItemKind::Union(ref struct_def, ref generics) => { self.head(&visibility_qualified(&item.vis, "union"))?; self.print_struct(struct_def, generics, item.ident, item.span, true)?; } ast::ItemKind::Impl(unsafety, polarity, defaultness, ref generics, ref opt_trait, ref ty, ref impl_items) => { self.head("")?; self.print_visibility(&item.vis)?; self.print_defaultness(defaultness)?; self.print_unsafety(unsafety)?; self.word_nbsp("impl")?; if !generics.params.is_empty() { self.print_generic_params(&generics.params)?; self.s.space()?; } if polarity == ast::ImplPolarity::Negative { self.s.word("!")?; } if let Some(ref t) = *opt_trait { self.print_trait_ref(t)?; self.s.space()?; self.word_space("for")?; } self.print_type(ty)?; self.print_where_clause(&generics.where_clause)?; self.s.space()?; self.bopen()?; self.print_inner_attributes(&item.attrs)?; for impl_item in impl_items { self.print_impl_item(impl_item)?; } self.bclose(item.span)?; } ast::ItemKind::Trait(is_auto, unsafety, ref generics, ref bounds, ref trait_items) => { self.head("")?; self.print_visibility(&item.vis)?; self.print_unsafety(unsafety)?; self.print_is_auto(is_auto)?; self.word_nbsp("trait")?; self.print_ident(item.ident)?; self.print_generic_params(&generics.params)?; let mut real_bounds = Vec::with_capacity(bounds.len()); for b in bounds.iter() { if let GenericBound::Trait(ref ptr, ast::TraitBoundModifier::Maybe) = *b { self.s.space()?; self.word_space("for ?")?; self.print_trait_ref(&ptr.trait_ref)?; } else { real_bounds.push(b.clone()); } } self.print_type_bounds(":", &real_bounds[..])?; self.print_where_clause(&generics.where_clause)?; self.s.word(" ")?; self.bopen()?; for trait_item in trait_items { self.print_trait_item(trait_item)?; } self.bclose(item.span)?; } ast::ItemKind::TraitAlias(ref generics, ref bounds) => { self.head("")?; self.print_visibility(&item.vis)?; self.word_nbsp("trait")?; self.print_ident(item.ident)?; self.print_generic_params(&generics.params)?; let mut real_bounds = Vec::with_capacity(bounds.len()); // FIXME(durka) this seems to be some quite outdated syntax for b in bounds.iter() { if let GenericBound::Trait(ref ptr, ast::TraitBoundModifier::Maybe) = *b { self.s.space()?; self.word_space("for ?")?; self.print_trait_ref(&ptr.trait_ref)?; } else { real_bounds.push(b.clone()); } } self.nbsp()?; self.print_type_bounds("=", &real_bounds[..])?; self.print_where_clause(&generics.where_clause)?; self.s.word(";")?; } ast::ItemKind::Mac(ref mac) => { if item.ident.name == keywords::Invalid.name() { self.print_mac(mac)?; match mac.node.delim { MacDelimiter::Brace => {} _ => self.s.word(";")?, } } else { self.print_path(&mac.node.path, false, 0)?; self.s.word("! ")?; self.print_ident(item.ident)?; self.cbox(INDENT_UNIT)?; self.popen()?; self.print_tts(mac.node.stream())?; self.pclose()?; self.s.word(";")?; self.end()?; } } ast::ItemKind::MacroDef(ref tts) => { self.s.word("macro_rules! ")?; self.print_ident(item.ident)?; self.cbox(INDENT_UNIT)?; self.popen()?; self.print_tts(tts.stream())?; self.pclose()?; self.s.word(";")?; self.end()?; } } self.ann.post(self, NodeItem(item)) } fn print_trait_ref(&mut self, t: &ast::TraitRef) -> io::Result<()> { self.print_path(&t.path, false, 0) } fn print_formal_generic_params( &mut self, generic_params: &[ast::GenericParam] ) -> io::Result<()> { if !generic_params.is_empty() { self.s.word("for")?; self.print_generic_params(generic_params)?; self.nbsp()?; } Ok(()) } fn print_poly_trait_ref(&mut self, t: &ast::PolyTraitRef) -> io::Result<()> { self.print_formal_generic_params(&t.bound_generic_params)?; self.print_trait_ref(&t.trait_ref) } pub fn print_enum_def(&mut self, enum_definition: &ast::EnumDef, generics: &ast::Generics, ident: ast::Ident, span: syntax_pos::Span, visibility: &ast::Visibility) -> io::Result<()> { self.head(&visibility_qualified(visibility, "enum"))?; self.print_ident(ident)?; self.print_generic_params(&generics.params)?; self.print_where_clause(&generics.where_clause)?; self.s.space()?; self.print_variants(&enum_definition.variants, span) } pub fn print_variants(&mut self, variants: &[ast::Variant], span: syntax_pos::Span) -> io::Result<()> { self.bopen()?; for v in variants { self.space_if_not_bol()?; self.maybe_print_comment(v.span.lo())?; self.print_outer_attributes(&v.node.attrs)?; self.ibox(INDENT_UNIT)?; self.print_variant(v)?; self.s.word(",")?; self.end()?; self.maybe_print_trailing_comment(v.span, None)?; } self.bclose(span) } pub fn print_visibility(&mut self, vis: &ast::Visibility) -> io::Result<()> { match vis.node { ast::VisibilityKind::Public => self.word_nbsp("pub"), ast::VisibilityKind::Crate(sugar) => match sugar { ast::CrateSugar::PubCrate => self.word_nbsp("pub(crate)"), ast::CrateSugar::JustCrate => self.word_nbsp("crate") } ast::VisibilityKind::Restricted { ref path, .. } => { let path = to_string(|s| s.print_path(path, false, 0)); if path == "self" || path == "super" { self.word_nbsp(&format!("pub({})", path)) } else { self.word_nbsp(&format!("pub(in {})", path)) } } ast::VisibilityKind::Inherited => Ok(()) } } pub fn print_defaultness(&mut self, defatulness: ast::Defaultness) -> io::Result<()> { if let ast::Defaultness::Default = defatulness { try!(self.word_nbsp("default")); } Ok(()) } pub fn print_struct(&mut self, struct_def: &ast::VariantData, generics: &ast::Generics, ident: ast::Ident, span: syntax_pos::Span, print_finalizer: bool) -> io::Result<()> { self.print_ident(ident)?; self.print_generic_params(&generics.params)?; if !struct_def.is_struct() { if struct_def.is_tuple() { self.popen()?; self.commasep( Inconsistent, struct_def.fields(), |s, field| { s.maybe_print_comment(field.span.lo())?; s.print_outer_attributes(&field.attrs)?; s.print_visibility(&field.vis)?; s.print_type(&field.ty) } )?; self.pclose()?; } self.print_where_clause(&generics.where_clause)?; if print_finalizer { self.s.word(";")?; } self.end()?; self.end() // close the outer-box } else { self.print_where_clause(&generics.where_clause)?; self.nbsp()?; self.bopen()?; self.hardbreak_if_not_bol()?; for field in struct_def.fields() { self.hardbreak_if_not_bol()?; self.maybe_print_comment(field.span.lo())?; self.print_outer_attributes(&field.attrs)?; self.print_visibility(&field.vis)?; self.print_ident(field.ident.unwrap())?; self.word_nbsp(":")?; self.print_type(&field.ty)?; self.s.word(",")?; } self.bclose(span) } } pub fn print_variant(&mut self, v: &ast::Variant) -> io::Result<()> { self.head("")?; let generics = ast::Generics::default(); self.print_struct(&v.node.data, &generics, v.node.ident, v.span, false)?; match v.node.disr_expr { Some(ref d) => { self.s.space()?; self.word_space("=")?; self.print_expr(&d.value) } _ => Ok(()) } } pub fn print_method_sig(&mut self, ident: ast::Ident, generics: &ast::Generics, m: &ast::MethodSig, vis: &ast::Visibility) -> io::Result<()> { self.print_fn(&m.decl, m.header, Some(ident), &generics, vis) } pub fn print_trait_item(&mut self, ti: &ast::TraitItem) -> io::Result<()> { self.ann.pre(self, NodeSubItem(ti.id))?; self.hardbreak_if_not_bol()?; self.maybe_print_comment(ti.span.lo())?; self.print_outer_attributes(&ti.attrs)?; match ti.node { ast::TraitItemKind::Const(ref ty, ref default) => { self.print_associated_const( ti.ident, ty, default.as_ref().map(|expr| &**expr), &codemap::respan(ti.span.shrink_to_lo(), ast::VisibilityKind::Inherited), )?; } ast::TraitItemKind::Method(ref sig, ref body) => { if body.is_some() { self.head("")?; } self.print_method_sig( ti.ident, &ti.generics, sig, &codemap::respan(ti.span.shrink_to_lo(), ast::VisibilityKind::Inherited), )?; if let Some(ref body) = *body { self.nbsp()?; self.print_block_with_attrs(body, &ti.attrs)?; } else { self.s.word(";")?; } } ast::TraitItemKind::Type(ref bounds, ref default) => { self.print_associated_type(ti.ident, Some(bounds), default.as_ref().map(|ty| &**ty))?; } ast::TraitItemKind::Macro(ref mac) => { self.print_mac(mac)?; match mac.node.delim { MacDelimiter::Brace => {} _ => self.s.word(";")?, } } } self.ann.post(self, NodeSubItem(ti.id)) } pub fn print_impl_item(&mut self, ii: &ast::ImplItem) -> io::Result<()> { self.ann.pre(self, NodeSubItem(ii.id))?; self.hardbreak_if_not_bol()?; self.maybe_print_comment(ii.span.lo())?; self.print_outer_attributes(&ii.attrs)?; self.print_defaultness(ii.defaultness)?; match ii.node { ast::ImplItemKind::Const(ref ty, ref expr) => { self.print_associated_const(ii.ident, ty, Some(expr), &ii.vis)?; } ast::ImplItemKind::Method(ref sig, ref body) => { self.head("")?; self.print_method_sig(ii.ident, &ii.generics, sig, &ii.vis)?; self.nbsp()?; self.print_block_with_attrs(body, &ii.attrs)?; } ast::ImplItemKind::Type(ref ty) => { self.print_associated_type(ii.ident, None, Some(ty))?; } ast::ImplItemKind::Macro(ref mac) => { self.print_mac(mac)?; match mac.node.delim { MacDelimiter::Brace => {} _ => self.s.word(";")?, } } } self.ann.post(self, NodeSubItem(ii.id)) } pub fn print_stmt(&mut self, st: &ast::Stmt) -> io::Result<()> { self.maybe_print_comment(st.span.lo())?; match st.node { ast::StmtKind::Local(ref loc) => { self.print_outer_attributes(&loc.attrs)?; self.space_if_not_bol()?; self.ibox(INDENT_UNIT)?; self.word_nbsp("let")?; self.ibox(INDENT_UNIT)?; self.print_local_decl(loc)?; self.end()?; if let Some(ref init) = loc.init { self.nbsp()?; self.word_space("=")?; self.print_expr(init)?; } self.s.word(";")?; self.end()?; } ast::StmtKind::Item(ref item) => self.print_item(item)?, ast::StmtKind::Expr(ref expr) => { self.space_if_not_bol()?; self.print_expr_outer_attr_style(expr, false)?; if parse::classify::expr_requires_semi_to_be_stmt(expr) { self.s.word(";")?; } } ast::StmtKind::Semi(ref expr) => { self.space_if_not_bol()?; self.print_expr_outer_attr_style(expr, false)?; self.s.word(";")?; } ast::StmtKind::Mac(ref mac) => { let (ref mac, style, ref attrs) = **mac; self.space_if_not_bol()?; self.print_outer_attributes(attrs)?; self.print_mac(mac)?; if style == ast::MacStmtStyle::Semicolon { self.s.word(";")?; } } } self.maybe_print_trailing_comment(st.span, None) } pub fn print_block(&mut self, blk: &ast::Block) -> io::Result<()> { self.print_block_with_attrs(blk, &[]) } pub fn print_block_unclosed(&mut self, blk: &ast::Block) -> io::Result<()> { self.print_block_unclosed_indent(blk, INDENT_UNIT) } pub fn print_block_unclosed_with_attrs(&mut self, blk: &ast::Block, attrs: &[ast::Attribute]) -> io::Result<()> { self.print_block_maybe_unclosed(blk, INDENT_UNIT, attrs, false) } pub fn print_block_unclosed_indent(&mut self, blk: &ast::Block, indented: usize) -> io::Result<()> { self.print_block_maybe_unclosed(blk, indented, &[], false) } pub fn print_block_with_attrs(&mut self, blk: &ast::Block, attrs: &[ast::Attribute]) -> io::Result<()> { self.print_block_maybe_unclosed(blk, INDENT_UNIT, attrs, true) } pub fn print_block_maybe_unclosed(&mut self, blk: &ast::Block, indented: usize, attrs: &[ast::Attribute], close_box: bool) -> io::Result<()> { match blk.rules { BlockCheckMode::Unsafe(..) => self.word_space("unsafe")?, BlockCheckMode::Default => () } self.maybe_print_comment(blk.span.lo())?; self.ann.pre(self, NodeBlock(blk))?; self.bopen()?; self.print_inner_attributes(attrs)?; for (i, st) in blk.stmts.iter().enumerate() { match st.node { ast::StmtKind::Expr(ref expr) if i == blk.stmts.len() - 1 => { self.maybe_print_comment(st.span.lo())?; self.space_if_not_bol()?; self.print_expr_outer_attr_style(expr, false)?; self.maybe_print_trailing_comment(expr.span, Some(blk.span.hi()))?; } _ => self.print_stmt(st)?, } } self.bclose_maybe_open(blk.span, indented, close_box)?; self.ann.post(self, NodeBlock(blk)) } fn print_else(&mut self, els: Option<&ast::Expr>) -> io::Result<()> { match els { Some(_else) => { match _else.node { // "another else-if" ast::ExprKind::If(ref i, ref then, ref e) => { self.cbox(INDENT_UNIT - 1)?; self.ibox(0)?; self.s.word(" else if ")?; self.print_expr_as_cond(i)?; self.s.space()?; self.print_block(then)?; self.print_else(e.as_ref().map(|e| &**e)) } // "another else-if-let" ast::ExprKind::IfLet(ref pats, ref expr, ref then, ref e) => { self.cbox(INDENT_UNIT - 1)?; self.ibox(0)?; self.s.word(" else if let ")?; self.print_pats(pats)?; self.s.space()?; self.word_space("=")?; self.print_expr_as_cond(expr)?; self.s.space()?; self.print_block(then)?; self.print_else(e.as_ref().map(|e| &**e)) } // "final else" ast::ExprKind::Block(ref b, _) => { self.cbox(INDENT_UNIT - 1)?; self.ibox(0)?; self.s.word(" else ")?; self.print_block(b) } // BLEAH, constraints would be great here _ => { panic!("print_if saw if with weird alternative"); } } } _ => Ok(()) } } pub fn print_if(&mut self, test: &ast::Expr, blk: &ast::Block, elseopt: Option<&ast::Expr>) -> io::Result<()> { self.head("if")?; self.print_expr_as_cond(test)?; self.s.space()?; self.print_block(blk)?; self.print_else(elseopt) } pub fn print_if_let(&mut self, pats: &[P], expr: &ast::Expr, blk: &ast::Block, elseopt: Option<&ast::Expr>) -> io::Result<()> { self.head("if let")?; self.print_pats(pats)?; self.s.space()?; self.word_space("=")?; self.print_expr_as_cond(expr)?; self.s.space()?; self.print_block(blk)?; self.print_else(elseopt) } pub fn print_mac(&mut self, m: &ast::Mac) -> io::Result<()> { self.print_path(&m.node.path, false, 0)?; self.s.word("!")?; match m.node.delim { MacDelimiter::Parenthesis => self.popen()?, MacDelimiter::Bracket => self.s.word("[")?, MacDelimiter::Brace => { self.head("")?; self.bopen()?; } } self.print_tts(m.node.stream())?; match m.node.delim { MacDelimiter::Parenthesis => self.pclose(), MacDelimiter::Bracket => self.s.word("]"), MacDelimiter::Brace => self.bclose(m.span), } } fn print_call_post(&mut self, args: &[P]) -> io::Result<()> { self.popen()?; self.commasep_exprs(Inconsistent, args)?; self.pclose() } pub fn print_expr_maybe_paren(&mut self, expr: &ast::Expr, prec: i8) -> io::Result<()> { let needs_par = expr.precedence().order() < prec; if needs_par { self.popen()?; } self.print_expr(expr)?; if needs_par { self.pclose()?; } Ok(()) } /// Print an expr using syntax that's acceptable in a condition position, such as the `cond` in /// `if cond { ... }`. pub fn print_expr_as_cond(&mut self, expr: &ast::Expr) -> io::Result<()> { let needs_par = match expr.node { // These cases need parens due to the parse error observed in #26461: `if return {}` // parses as the erroneous construct `if (return {})`, not `if (return) {}`. ast::ExprKind::Closure(..) | ast::ExprKind::Ret(..) | ast::ExprKind::Break(..) => true, _ => parser::contains_exterior_struct_lit(expr), }; if needs_par { self.popen()?; } self.print_expr(expr)?; if needs_par { self.pclose()?; } Ok(()) } fn print_expr_vec(&mut self, exprs: &[P], attrs: &[Attribute]) -> io::Result<()> { self.ibox(INDENT_UNIT)?; self.s.word("[")?; self.print_inner_attributes_inline(attrs)?; self.commasep_exprs(Inconsistent, &exprs[..])?; self.s.word("]")?; self.end() } fn print_expr_repeat(&mut self, element: &ast::Expr, count: &ast::AnonConst, attrs: &[Attribute]) -> io::Result<()> { self.ibox(INDENT_UNIT)?; self.s.word("[")?; self.print_inner_attributes_inline(attrs)?; self.print_expr(element)?; self.word_space(";")?; self.print_expr(&count.value)?; self.s.word("]")?; self.end() } fn print_expr_struct(&mut self, path: &ast::Path, fields: &[ast::Field], wth: &Option>, attrs: &[Attribute]) -> io::Result<()> { self.print_path(path, true, 0)?; self.s.word("{")?; self.print_inner_attributes_inline(attrs)?; self.commasep_cmnt( Consistent, &fields[..], |s, field| { s.ibox(INDENT_UNIT)?; if !field.is_shorthand { s.print_ident(field.ident)?; s.word_space(":")?; } s.print_expr(&field.expr)?; s.end() }, |f| f.span)?; match *wth { Some(ref expr) => { self.ibox(INDENT_UNIT)?; if !fields.is_empty() { self.s.word(",")?; self.s.space()?; } self.s.word("..")?; self.print_expr(expr)?; self.end()?; } _ => if !fields.is_empty() { self.s.word(",")? } } self.s.word("}")?; Ok(()) } fn print_expr_tup(&mut self, exprs: &[P], attrs: &[Attribute]) -> io::Result<()> { self.popen()?; self.print_inner_attributes_inline(attrs)?; self.commasep_exprs(Inconsistent, &exprs[..])?; if exprs.len() == 1 { self.s.word(",")?; } self.pclose() } fn print_expr_call(&mut self, func: &ast::Expr, args: &[P]) -> io::Result<()> { let prec = match func.node { ast::ExprKind::Field(..) => parser::PREC_FORCE_PAREN, _ => parser::PREC_POSTFIX, }; self.print_expr_maybe_paren(func, prec)?; self.print_call_post(args) } fn print_expr_method_call(&mut self, segment: &ast::PathSegment, args: &[P]) -> io::Result<()> { let base_args = &args[1..]; self.print_expr_maybe_paren(&args[0], parser::PREC_POSTFIX)?; self.s.word(".")?; self.print_ident(segment.ident)?; if let Some(ref args) = segment.args { self.print_generic_args(args, true)?; } self.print_call_post(base_args) } fn print_expr_binary(&mut self, op: ast::BinOp, lhs: &ast::Expr, rhs: &ast::Expr) -> io::Result<()> { let assoc_op = AssocOp::from_ast_binop(op.node); let prec = assoc_op.precedence() as i8; let fixity = assoc_op.fixity(); let (left_prec, right_prec) = match fixity { Fixity::Left => (prec, prec + 1), Fixity::Right => (prec + 1, prec), Fixity::None => (prec + 1, prec + 1), }; let left_prec = match (&lhs.node, op.node) { // These cases need parens: `x as i32 < y` has the parser thinking that `i32 < y` is // the beginning of a path type. It starts trying to parse `x as (i32 < y ...` instead // of `(x as i32) < ...`. We need to convince it _not_ to do that. (&ast::ExprKind::Cast { .. }, ast::BinOpKind::Lt) | (&ast::ExprKind::Cast { .. }, ast::BinOpKind::Shl) => parser::PREC_FORCE_PAREN, _ => left_prec, }; self.print_expr_maybe_paren(lhs, left_prec)?; self.s.space()?; self.word_space(op.node.to_string())?; self.print_expr_maybe_paren(rhs, right_prec) } fn print_expr_unary(&mut self, op: ast::UnOp, expr: &ast::Expr) -> io::Result<()> { self.s.word(ast::UnOp::to_string(op))?; self.print_expr_maybe_paren(expr, parser::PREC_PREFIX) } fn print_expr_addr_of(&mut self, mutability: ast::Mutability, expr: &ast::Expr) -> io::Result<()> { self.s.word("&")?; self.print_mutability(mutability)?; self.print_expr_maybe_paren(expr, parser::PREC_PREFIX) } pub fn print_expr(&mut self, expr: &ast::Expr) -> io::Result<()> { self.print_expr_outer_attr_style(expr, true) } fn print_expr_outer_attr_style(&mut self, expr: &ast::Expr, is_inline: bool) -> io::Result<()> { self.maybe_print_comment(expr.span.lo())?; let attrs = &expr.attrs; if is_inline { self.print_outer_attributes_inline(attrs)?; } else { self.print_outer_attributes(attrs)?; } self.ibox(INDENT_UNIT)?; self.ann.pre(self, NodeExpr(expr))?; match expr.node { ast::ExprKind::Box(ref expr) => { self.word_space("box")?; self.print_expr_maybe_paren(expr, parser::PREC_PREFIX)?; } ast::ExprKind::ObsoleteInPlace(ref place, ref expr) => { let prec = AssocOp::ObsoleteInPlace.precedence() as i8; self.print_expr_maybe_paren(place, prec + 1)?; self.s.space()?; self.word_space("<-")?; self.print_expr_maybe_paren(expr, prec)?; } ast::ExprKind::Array(ref exprs) => { self.print_expr_vec(&exprs[..], attrs)?; } ast::ExprKind::Repeat(ref element, ref count) => { self.print_expr_repeat(element, count, attrs)?; } ast::ExprKind::Struct(ref path, ref fields, ref wth) => { self.print_expr_struct(path, &fields[..], wth, attrs)?; } ast::ExprKind::Tup(ref exprs) => { self.print_expr_tup(&exprs[..], attrs)?; } ast::ExprKind::Call(ref func, ref args) => { self.print_expr_call(func, &args[..])?; } ast::ExprKind::MethodCall(ref segment, ref args) => { self.print_expr_method_call(segment, &args[..])?; } ast::ExprKind::Binary(op, ref lhs, ref rhs) => { self.print_expr_binary(op, lhs, rhs)?; } ast::ExprKind::Unary(op, ref expr) => { self.print_expr_unary(op, expr)?; } ast::ExprKind::AddrOf(m, ref expr) => { self.print_expr_addr_of(m, expr)?; } ast::ExprKind::Lit(ref lit) => { self.print_literal(lit)?; } ast::ExprKind::Cast(ref expr, ref ty) => { let prec = AssocOp::As.precedence() as i8; self.print_expr_maybe_paren(expr, prec)?; self.s.space()?; self.word_space("as")?; self.print_type(ty)?; } ast::ExprKind::Type(ref expr, ref ty) => { let prec = AssocOp::Colon.precedence() as i8; self.print_expr_maybe_paren(expr, prec)?; self.word_space(":")?; self.print_type(ty)?; } ast::ExprKind::If(ref test, ref blk, ref elseopt) => { self.print_if(test, blk, elseopt.as_ref().map(|e| &**e))?; } ast::ExprKind::IfLet(ref pats, ref expr, ref blk, ref elseopt) => { self.print_if_let(pats, expr, blk, elseopt.as_ref().map(|e| &**e))?; } ast::ExprKind::While(ref test, ref blk, opt_label) => { if let Some(label) = opt_label { self.print_ident(label.ident)?; self.word_space(":")?; } self.head("while")?; self.print_expr_as_cond(test)?; self.s.space()?; self.print_block_with_attrs(blk, attrs)?; } ast::ExprKind::WhileLet(ref pats, ref expr, ref blk, opt_label) => { if let Some(label) = opt_label { self.print_ident(label.ident)?; self.word_space(":")?; } self.head("while let")?; self.print_pats(pats)?; self.s.space()?; self.word_space("=")?; self.print_expr_as_cond(expr)?; self.s.space()?; self.print_block_with_attrs(blk, attrs)?; } ast::ExprKind::ForLoop(ref pat, ref iter, ref blk, opt_label) => { if let Some(label) = opt_label { self.print_ident(label.ident)?; self.word_space(":")?; } self.head("for")?; self.print_pat(pat)?; self.s.space()?; self.word_space("in")?; self.print_expr_as_cond(iter)?; self.s.space()?; self.print_block_with_attrs(blk, attrs)?; } ast::ExprKind::Loop(ref blk, opt_label) => { if let Some(label) = opt_label { self.print_ident(label.ident)?; self.word_space(":")?; } self.head("loop")?; self.s.space()?; self.print_block_with_attrs(blk, attrs)?; } ast::ExprKind::Match(ref expr, ref arms) => { self.cbox(INDENT_UNIT)?; self.ibox(4)?; self.word_nbsp("match")?; self.print_expr_as_cond(expr)?; self.s.space()?; self.bopen()?; self.print_inner_attributes_no_trailing_hardbreak(attrs)?; for arm in arms { self.print_arm(arm)?; } self.bclose_(expr.span, INDENT_UNIT)?; } ast::ExprKind::Closure( capture_clause, asyncness, movability, ref decl, ref body, _) => { self.print_movability(movability)?; self.print_asyncness(asyncness)?; self.print_capture_clause(capture_clause)?; self.print_fn_block_args(decl)?; self.s.space()?; self.print_expr(body)?; self.end()?; // need to close a box // a box will be closed by print_expr, but we didn't want an overall // wrapper so we closed the corresponding opening. so create an // empty box to satisfy the close. self.ibox(0)?; } ast::ExprKind::Block(ref blk, opt_label) => { if let Some(label) = opt_label { self.print_ident(label.ident)?; self.word_space(":")?; } // containing cbox, will be closed by print-block at } self.cbox(INDENT_UNIT)?; // head-box, will be closed by print-block after { self.ibox(0)?; self.print_block_with_attrs(blk, attrs)?; } ast::ExprKind::Async(capture_clause, _, ref blk) => { self.word_nbsp("async")?; self.print_capture_clause(capture_clause)?; self.s.space()?; self.print_block_with_attrs(blk, attrs)?; } ast::ExprKind::Assign(ref lhs, ref rhs) => { let prec = AssocOp::Assign.precedence() as i8; self.print_expr_maybe_paren(lhs, prec + 1)?; self.s.space()?; self.word_space("=")?; self.print_expr_maybe_paren(rhs, prec)?; } ast::ExprKind::AssignOp(op, ref lhs, ref rhs) => { let prec = AssocOp::Assign.precedence() as i8; self.print_expr_maybe_paren(lhs, prec + 1)?; self.s.space()?; self.s.word(op.node.to_string())?; self.word_space("=")?; self.print_expr_maybe_paren(rhs, prec)?; } ast::ExprKind::Field(ref expr, ident) => { self.print_expr_maybe_paren(expr, parser::PREC_POSTFIX)?; self.s.word(".")?; self.print_ident(ident)?; } ast::ExprKind::Index(ref expr, ref index) => { self.print_expr_maybe_paren(expr, parser::PREC_POSTFIX)?; self.s.word("[")?; self.print_expr(index)?; self.s.word("]")?; } ast::ExprKind::Range(ref start, ref end, limits) => { // Special case for `Range`. `AssocOp` claims that `Range` has higher precedence // than `Assign`, but `x .. x = x` gives a parse error instead of `x .. (x = x)`. // Here we use a fake precedence value so that any child with lower precedence than // a "normal" binop gets parenthesized. (`LOr` is the lowest-precedence binop.) let fake_prec = AssocOp::LOr.precedence() as i8; if let Some(ref e) = *start { self.print_expr_maybe_paren(e, fake_prec)?; } if limits == ast::RangeLimits::HalfOpen { self.s.word("..")?; } else { self.s.word("..=")?; } if let Some(ref e) = *end { self.print_expr_maybe_paren(e, fake_prec)?; } } ast::ExprKind::Path(None, ref path) => { self.print_path(path, true, 0)? } ast::ExprKind::Path(Some(ref qself), ref path) => { self.print_qpath(path, qself, true)? } ast::ExprKind::Break(opt_label, ref opt_expr) => { self.s.word("break")?; self.s.space()?; if let Some(label) = opt_label { self.print_ident(label.ident)?; self.s.space()?; } if let Some(ref expr) = *opt_expr { self.print_expr_maybe_paren(expr, parser::PREC_JUMP)?; self.s.space()?; } } ast::ExprKind::Continue(opt_label) => { self.s.word("continue")?; self.s.space()?; if let Some(label) = opt_label { self.print_ident(label.ident)?; self.s.space()? } } ast::ExprKind::Ret(ref result) => { self.s.word("return")?; if let Some(ref expr) = *result { self.s.word(" ")?; self.print_expr_maybe_paren(expr, parser::PREC_JUMP)?; } } ast::ExprKind::InlineAsm(ref a) => { self.s.word("asm!")?; self.popen()?; self.print_string(&a.asm.as_str(), a.asm_str_style)?; self.word_space(":")?; self.commasep(Inconsistent, &a.outputs, |s, out| { let constraint = out.constraint.as_str(); let mut ch = constraint.chars(); match ch.next() { Some('=') if out.is_rw => { s.print_string(&format!("+{}", ch.as_str()), ast::StrStyle::Cooked)? } _ => s.print_string(&constraint, ast::StrStyle::Cooked)? } s.popen()?; s.print_expr(&out.expr)?; s.pclose()?; Ok(()) })?; self.s.space()?; self.word_space(":")?; self.commasep(Inconsistent, &a.inputs, |s, &(co, ref o)| { s.print_string(&co.as_str(), ast::StrStyle::Cooked)?; s.popen()?; s.print_expr(o)?; s.pclose()?; Ok(()) })?; self.s.space()?; self.word_space(":")?; self.commasep(Inconsistent, &a.clobbers, |s, co| { s.print_string(&co.as_str(), ast::StrStyle::Cooked)?; Ok(()) })?; let mut options = vec![]; if a.volatile { options.push("volatile"); } if a.alignstack { options.push("alignstack"); } if a.dialect == ast::AsmDialect::Intel { options.push("intel"); } if !options.is_empty() { self.s.space()?; self.word_space(":")?; self.commasep(Inconsistent, &options, |s, &co| { s.print_string(co, ast::StrStyle::Cooked)?; Ok(()) })?; } self.pclose()?; } ast::ExprKind::Mac(ref m) => self.print_mac(m)?, ast::ExprKind::Paren(ref e) => { self.popen()?; self.print_inner_attributes_inline(attrs)?; self.print_expr(e)?; self.pclose()?; }, ast::ExprKind::Yield(ref e) => { self.s.word("yield")?; match *e { Some(ref expr) => { self.s.space()?; self.print_expr_maybe_paren(expr, parser::PREC_JUMP)?; } _ => () } } ast::ExprKind::Try(ref e) => { self.print_expr_maybe_paren(e, parser::PREC_POSTFIX)?; self.s.word("?")? } ast::ExprKind::Catch(ref blk) => { self.head("do catch")?; self.s.space()?; self.print_block_with_attrs(blk, attrs)? } } self.ann.post(self, NodeExpr(expr))?; self.end() } pub fn print_local_decl(&mut self, loc: &ast::Local) -> io::Result<()> { self.print_pat(&loc.pat)?; if let Some(ref ty) = loc.ty { self.word_space(":")?; self.print_type(ty)?; } Ok(()) } pub fn print_ident(&mut self, ident: ast::Ident) -> io::Result<()> { if ident.is_raw_guess() { self.s.word(&format!("r#{}", ident))?; } else { self.s.word(&ident.as_str())?; } self.ann.post(self, NodeIdent(&ident)) } pub fn print_usize(&mut self, i: usize) -> io::Result<()> { self.s.word(&i.to_string()) } pub fn print_name(&mut self, name: ast::Name) -> io::Result<()> { self.s.word(&name.as_str())?; self.ann.post(self, NodeName(&name)) } pub fn print_for_decl(&mut self, loc: &ast::Local, coll: &ast::Expr) -> io::Result<()> { self.print_local_decl(loc)?; self.s.space()?; self.word_space("in")?; self.print_expr(coll) } fn print_path(&mut self, path: &ast::Path, colons_before_params: bool, depth: usize) -> io::Result<()> { self.maybe_print_comment(path.span.lo())?; for (i, segment) in path.segments[..path.segments.len() - depth].iter().enumerate() { if i > 0 { self.s.word("::")? } self.print_path_segment(segment, colons_before_params)?; } Ok(()) } fn print_path_segment(&mut self, segment: &ast::PathSegment, colons_before_params: bool) -> io::Result<()> { if segment.ident.name != keywords::CrateRoot.name() && segment.ident.name != keywords::DollarCrate.name() { self.print_ident(segment.ident)?; if let Some(ref args) = segment.args { self.print_generic_args(args, colons_before_params)?; } } else if segment.ident.name == keywords::DollarCrate.name() { self.print_dollar_crate(segment.ident.span.ctxt())?; } Ok(()) } fn print_qpath(&mut self, path: &ast::Path, qself: &ast::QSelf, colons_before_params: bool) -> io::Result<()> { self.s.word("<")?; self.print_type(&qself.ty)?; if qself.position > 0 { self.s.space()?; self.word_space("as")?; let depth = path.segments.len() - qself.position; self.print_path(path, false, depth)?; } self.s.word(">")?; self.s.word("::")?; let item_segment = path.segments.last().unwrap(); self.print_ident(item_segment.ident)?; match item_segment.args { Some(ref args) => self.print_generic_args(args, colons_before_params), None => Ok(()), } } fn print_generic_args(&mut self, args: &ast::GenericArgs, colons_before_params: bool) -> io::Result<()> { if colons_before_params { self.s.word("::")? } match *args { ast::GenericArgs::AngleBracketed(ref data) => { self.s.word("<")?; self.commasep(Inconsistent, &data.args, |s, generic_arg| { s.print_generic_arg(generic_arg) })?; let mut comma = data.args.len() != 0; for binding in data.bindings.iter() { if comma { self.word_space(",")? } self.print_ident(binding.ident)?; self.s.space()?; self.word_space("=")?; self.print_type(&binding.ty)?; comma = true; } self.s.word(">")? } ast::GenericArgs::Parenthesized(ref data) => { self.s.word("(")?; self.commasep( Inconsistent, &data.inputs, |s, ty| s.print_type(ty))?; self.s.word(")")?; if let Some(ref ty) = data.output { self.space_if_not_bol()?; self.word_space("->")?; self.print_type(ty)?; } } } Ok(()) } pub fn print_pat(&mut self, pat: &ast::Pat) -> io::Result<()> { self.maybe_print_comment(pat.span.lo())?; self.ann.pre(self, NodePat(pat))?; /* Pat isn't normalized, but the beauty of it is that it doesn't matter */ match pat.node { PatKind::Wild => self.s.word("_")?, PatKind::Ident(binding_mode, ident, ref sub) => { match binding_mode { ast::BindingMode::ByRef(mutbl) => { self.word_nbsp("ref")?; self.print_mutability(mutbl)?; } ast::BindingMode::ByValue(ast::Mutability::Immutable) => {} ast::BindingMode::ByValue(ast::Mutability::Mutable) => { self.word_nbsp("mut")?; } } self.print_ident(ident)?; if let Some(ref p) = *sub { self.s.word("@")?; self.print_pat(p)?; } } PatKind::TupleStruct(ref path, ref elts, ddpos) => { self.print_path(path, true, 0)?; self.popen()?; if let Some(ddpos) = ddpos { self.commasep(Inconsistent, &elts[..ddpos], |s, p| s.print_pat(p))?; if ddpos != 0 { self.word_space(",")?; } self.s.word("..")?; if ddpos != elts.len() { self.s.word(",")?; self.commasep(Inconsistent, &elts[ddpos..], |s, p| s.print_pat(p))?; } } else { self.commasep(Inconsistent, &elts[..], |s, p| s.print_pat(p))?; } self.pclose()?; } PatKind::Path(None, ref path) => { self.print_path(path, true, 0)?; } PatKind::Path(Some(ref qself), ref path) => { self.print_qpath(path, qself, false)?; } PatKind::Struct(ref path, ref fields, etc) => { self.print_path(path, true, 0)?; self.nbsp()?; self.word_space("{")?; self.commasep_cmnt( Consistent, &fields[..], |s, f| { s.cbox(INDENT_UNIT)?; if !f.node.is_shorthand { s.print_ident(f.node.ident)?; s.word_nbsp(":")?; } s.print_pat(&f.node.pat)?; s.end() }, |f| f.node.pat.span)?; if etc { if !fields.is_empty() { self.word_space(",")?; } self.s.word("..")?; } self.s.space()?; self.s.word("}")?; } PatKind::Tuple(ref elts, ddpos) => { self.popen()?; if let Some(ddpos) = ddpos { self.commasep(Inconsistent, &elts[..ddpos], |s, p| s.print_pat(p))?; if ddpos != 0 { self.word_space(",")?; } self.s.word("..")?; if ddpos != elts.len() { self.s.word(",")?; self.commasep(Inconsistent, &elts[ddpos..], |s, p| s.print_pat(p))?; } } else { self.commasep(Inconsistent, &elts[..], |s, p| s.print_pat(p))?; if elts.len() == 1 { self.s.word(",")?; } } self.pclose()?; } PatKind::Box(ref inner) => { self.s.word("box ")?; self.print_pat(inner)?; } PatKind::Ref(ref inner, mutbl) => { self.s.word("&")?; if mutbl == ast::Mutability::Mutable { self.s.word("mut ")?; } self.print_pat(inner)?; } PatKind::Lit(ref e) => self.print_expr(&**e)?, PatKind::Range(ref begin, ref end, Spanned { node: ref end_kind, .. }) => { self.print_expr(begin)?; self.s.space()?; match *end_kind { RangeEnd::Included(RangeSyntax::DotDotDot) => self.s.word("...")?, RangeEnd::Included(RangeSyntax::DotDotEq) => self.s.word("..=")?, RangeEnd::Excluded => self.s.word("..")?, } self.print_expr(end)?; } PatKind::Slice(ref before, ref slice, ref after) => { self.s.word("[")?; self.commasep(Inconsistent, &before[..], |s, p| s.print_pat(p))?; if let Some(ref p) = *slice { if !before.is_empty() { self.word_space(",")?; } if let PatKind::Wild = p.node { // Print nothing } else { self.print_pat(p)?; } self.s.word("..")?; if !after.is_empty() { self.word_space(",")?; } } self.commasep(Inconsistent, &after[..], |s, p| s.print_pat(p))?; self.s.word("]")?; } PatKind::Paren(ref inner) => { self.popen()?; self.print_pat(inner)?; self.pclose()?; } PatKind::Mac(ref m) => self.print_mac(m)?, } self.ann.post(self, NodePat(pat)) } fn print_pats(&mut self, pats: &[P]) -> io::Result<()> { let mut first = true; for p in pats { if first { first = false; } else { self.s.space()?; self.word_space("|")?; } self.print_pat(p)?; } Ok(()) } fn print_arm(&mut self, arm: &ast::Arm) -> io::Result<()> { // I have no idea why this check is necessary, but here it // is :( if arm.attrs.is_empty() { self.s.space()?; } self.cbox(INDENT_UNIT)?; self.ibox(0)?; self.maybe_print_comment(arm.pats[0].span.lo())?; self.print_outer_attributes(&arm.attrs)?; self.print_pats(&arm.pats)?; self.s.space()?; if let Some(ref e) = arm.guard { self.word_space("if")?; self.print_expr(e)?; self.s.space()?; } self.word_space("=>")?; match arm.body.node { ast::ExprKind::Block(ref blk, opt_label) => { if let Some(label) = opt_label { self.print_ident(label.ident)?; self.word_space(":")?; } // the block will close the pattern's ibox self.print_block_unclosed_indent(blk, INDENT_UNIT)?; // If it is a user-provided unsafe block, print a comma after it if let BlockCheckMode::Unsafe(ast::UserProvided) = blk.rules { self.s.word(",")?; } } _ => { self.end()?; // close the ibox for the pattern self.print_expr(&arm.body)?; self.s.word(",")?; } } self.end() // close enclosing cbox } fn print_explicit_self(&mut self, explicit_self: &ast::ExplicitSelf) -> io::Result<()> { match explicit_self.node { SelfKind::Value(m) => { self.print_mutability(m)?; self.s.word("self") } SelfKind::Region(ref lt, m) => { self.s.word("&")?; self.print_opt_lifetime(lt)?; self.print_mutability(m)?; self.s.word("self") } SelfKind::Explicit(ref typ, m) => { self.print_mutability(m)?; self.s.word("self")?; self.word_space(":")?; self.print_type(typ) } } } pub fn print_fn(&mut self, decl: &ast::FnDecl, header: ast::FnHeader, name: Option, generics: &ast::Generics, vis: &ast::Visibility) -> io::Result<()> { self.print_fn_header_info(header, vis)?; if let Some(name) = name { self.nbsp()?; self.print_ident(name)?; } self.print_generic_params(&generics.params)?; self.print_fn_args_and_ret(decl)?; self.print_where_clause(&generics.where_clause) } pub fn print_fn_args_and_ret(&mut self, decl: &ast::FnDecl) -> io::Result<()> { self.popen()?; self.commasep(Inconsistent, &decl.inputs, |s, arg| s.print_arg(arg, false))?; if decl.variadic { self.s.word(", ...")?; } self.pclose()?; self.print_fn_output(decl) } pub fn print_fn_block_args( &mut self, decl: &ast::FnDecl) -> io::Result<()> { self.s.word("|")?; self.commasep(Inconsistent, &decl.inputs, |s, arg| s.print_arg(arg, true))?; self.s.word("|")?; if let ast::FunctionRetTy::Default(..) = decl.output { return Ok(()); } self.space_if_not_bol()?; self.word_space("->")?; match decl.output { ast::FunctionRetTy::Ty(ref ty) => { self.print_type(ty)?; self.maybe_print_comment(ty.span.lo()) } ast::FunctionRetTy::Default(..) => unreachable!(), } } pub fn print_movability(&mut self, movability: ast::Movability) -> io::Result<()> { match movability { ast::Movability::Static => self.word_space("static"), ast::Movability::Movable => Ok(()), } } pub fn print_asyncness(&mut self, asyncness: ast::IsAsync) -> io::Result<()> { if asyncness.is_async() { self.word_nbsp("async")?; } Ok(()) } pub fn print_capture_clause(&mut self, capture_clause: ast::CaptureBy) -> io::Result<()> { match capture_clause { ast::CaptureBy::Value => self.word_space("move"), ast::CaptureBy::Ref => Ok(()), } } pub fn print_type_bounds(&mut self, prefix: &str, bounds: &[ast::GenericBound]) -> io::Result<()> { if !bounds.is_empty() { self.s.word(prefix)?; let mut first = true; for bound in bounds { if !(first && prefix.is_empty()) { self.nbsp()?; } if first { first = false; } else { self.word_space("+")?; } match bound { GenericBound::Trait(tref, modifier) => { if modifier == &TraitBoundModifier::Maybe { self.s.word("?")?; } self.print_poly_trait_ref(tref)?; } GenericBound::Outlives(lt) => self.print_lifetime(*lt)?, } } } Ok(()) } pub fn print_lifetime(&mut self, lifetime: ast::Lifetime) -> io::Result<()> { self.print_name(lifetime.ident.name) } pub fn print_lifetime_bounds(&mut self, lifetime: ast::Lifetime, bounds: &ast::GenericBounds) -> io::Result<()> { self.print_lifetime(lifetime)?; if !bounds.is_empty() { self.s.word(": ")?; for (i, bound) in bounds.iter().enumerate() { if i != 0 { self.s.word(" + ")?; } match bound { ast::GenericBound::Outlives(lt) => self.print_lifetime(*lt)?, _ => panic!(), } } } Ok(()) } pub fn print_generic_params( &mut self, generic_params: &[ast::GenericParam] ) -> io::Result<()> { if generic_params.is_empty() { return Ok(()); } self.s.word("<")?; self.commasep(Inconsistent, &generic_params, |s, param| { match param.kind { ast::GenericParamKind::Lifetime => { s.print_outer_attributes_inline(¶m.attrs)?; let lt = ast::Lifetime { id: param.id, ident: param.ident }; s.print_lifetime_bounds(lt, ¶m.bounds) }, ast::GenericParamKind::Type { ref default } => { s.print_outer_attributes_inline(¶m.attrs)?; s.print_ident(param.ident)?; s.print_type_bounds(":", ¶m.bounds)?; match default { Some(ref default) => { s.s.space()?; s.word_space("=")?; s.print_type(default) } _ => Ok(()) } } } })?; self.s.word(">")?; Ok(()) } pub fn print_where_clause(&mut self, where_clause: &ast::WhereClause) -> io::Result<()> { if where_clause.predicates.is_empty() { return Ok(()) } self.s.space()?; self.word_space("where")?; for (i, predicate) in where_clause.predicates.iter().enumerate() { if i != 0 { self.word_space(",")?; } match *predicate { ast::WherePredicate::BoundPredicate(ast::WhereBoundPredicate { ref bound_generic_params, ref bounded_ty, ref bounds, .. }) => { self.print_formal_generic_params(bound_generic_params)?; self.print_type(bounded_ty)?; self.print_type_bounds(":", bounds)?; } ast::WherePredicate::RegionPredicate(ast::WhereRegionPredicate{ref lifetime, ref bounds, ..}) => { self.print_lifetime_bounds(*lifetime, bounds)?; } ast::WherePredicate::EqPredicate(ast::WhereEqPredicate{ref lhs_ty, ref rhs_ty, ..}) => { self.print_type(lhs_ty)?; self.s.space()?; self.word_space("=")?; self.print_type(rhs_ty)?; } } } Ok(()) } pub fn print_use_tree(&mut self, tree: &ast::UseTree) -> io::Result<()> { match tree.kind { ast::UseTreeKind::Simple(rename, ..) => { self.print_path(&tree.prefix, false, 0)?; if let Some(rename) = rename { self.s.space()?; self.word_space("as")?; self.print_ident(rename)?; } } ast::UseTreeKind::Glob => { if !tree.prefix.segments.is_empty() { self.print_path(&tree.prefix, false, 0)?; self.s.word("::")?; } self.s.word("*")?; } ast::UseTreeKind::Nested(ref items) => { if tree.prefix.segments.is_empty() { self.s.word("{")?; } else { self.print_path(&tree.prefix, false, 0)?; self.s.word("::{")?; } self.commasep(Inconsistent, &items[..], |this, &(ref tree, _)| { this.print_use_tree(tree) })?; self.s.word("}")?; } } Ok(()) } pub fn print_mutability(&mut self, mutbl: ast::Mutability) -> io::Result<()> { match mutbl { ast::Mutability::Mutable => self.word_nbsp("mut"), ast::Mutability::Immutable => Ok(()), } } pub fn print_mt(&mut self, mt: &ast::MutTy) -> io::Result<()> { self.print_mutability(mt.mutbl)?; self.print_type(&mt.ty) } pub fn print_arg(&mut self, input: &ast::Arg, is_closure: bool) -> io::Result<()> { self.ibox(INDENT_UNIT)?; match input.ty.node { ast::TyKind::Infer if is_closure => self.print_pat(&input.pat)?, _ => { if let Some(eself) = input.to_self() { self.print_explicit_self(&eself)?; } else { let invalid = if let PatKind::Ident(_, ident, _) = input.pat.node { ident.name == keywords::Invalid.name() } else { false }; if !invalid { self.print_pat(&input.pat)?; self.s.word(":")?; self.s.space()?; } self.print_type(&input.ty)?; } } } self.end() } pub fn print_fn_output(&mut self, decl: &ast::FnDecl) -> io::Result<()> { if let ast::FunctionRetTy::Default(..) = decl.output { return Ok(()); } self.space_if_not_bol()?; self.ibox(INDENT_UNIT)?; self.word_space("->")?; match decl.output { ast::FunctionRetTy::Default(..) => unreachable!(), ast::FunctionRetTy::Ty(ref ty) => self.print_type(ty)? } self.end()?; match decl.output { ast::FunctionRetTy::Ty(ref output) => self.maybe_print_comment(output.span.lo()), _ => Ok(()) } } pub fn print_ty_fn(&mut self, abi: abi::Abi, unsafety: ast::Unsafety, decl: &ast::FnDecl, name: Option, generic_params: &Vec) -> io::Result<()> { self.ibox(INDENT_UNIT)?; if !generic_params.is_empty() { self.s.word("for")?; self.print_generic_params(generic_params)?; } let generics = ast::Generics { params: Vec::new(), where_clause: ast::WhereClause { id: ast::DUMMY_NODE_ID, predicates: Vec::new(), span: syntax_pos::DUMMY_SP, }, span: syntax_pos::DUMMY_SP, }; self.print_fn(decl, ast::FnHeader { unsafety, abi, ..ast::FnHeader::default() }, name, &generics, &codemap::dummy_spanned(ast::VisibilityKind::Inherited))?; self.end() } pub fn maybe_print_trailing_comment(&mut self, span: syntax_pos::Span, next_pos: Option) -> io::Result<()> { let cm = match self.cm { Some(cm) => cm, _ => return Ok(()) }; if let Some(ref cmnt) = self.next_comment() { if cmnt.style != comments::Trailing { return Ok(()) } let span_line = cm.lookup_char_pos(span.hi()); let comment_line = cm.lookup_char_pos(cmnt.pos); let next = next_pos.unwrap_or(cmnt.pos + BytePos(1)); if span.hi() < cmnt.pos && cmnt.pos < next && span_line.line == comment_line.line { self.print_comment(cmnt)?; } } Ok(()) } pub fn print_remaining_comments(&mut self) -> io::Result<()> { // If there aren't any remaining comments, then we need to manually // make sure there is a line break at the end. if self.next_comment().is_none() { self.s.hardbreak()?; } while let Some(ref cmnt) = self.next_comment() { self.print_comment(cmnt)?; } Ok(()) } pub fn print_opt_abi_and_extern_if_nondefault(&mut self, opt_abi: Option) -> io::Result<()> { match opt_abi { Some(Abi::Rust) => Ok(()), Some(abi) => { self.word_nbsp("extern")?; self.word_nbsp(&abi.to_string()) } None => Ok(()) } } pub fn print_extern_opt_abi(&mut self, opt_abi: Option) -> io::Result<()> { match opt_abi { Some(abi) => { self.word_nbsp("extern")?; self.word_nbsp(&abi.to_string()) } None => Ok(()) } } pub fn print_fn_header_info(&mut self, header: ast::FnHeader, vis: &ast::Visibility) -> io::Result<()> { self.s.word(&visibility_qualified(vis, ""))?; match header.constness.node { ast::Constness::NotConst => {} ast::Constness::Const => self.word_nbsp("const")? } self.print_asyncness(header.asyncness)?; self.print_unsafety(header.unsafety)?; if header.abi != Abi::Rust { self.word_nbsp("extern")?; self.word_nbsp(&header.abi.to_string())?; } self.s.word("fn") } pub fn print_unsafety(&mut self, s: ast::Unsafety) -> io::Result<()> { match s { ast::Unsafety::Normal => Ok(()), ast::Unsafety::Unsafe => self.word_nbsp("unsafe"), } } pub fn print_is_auto(&mut self, s: ast::IsAuto) -> io::Result<()> { match s { ast::IsAuto::Yes => self.word_nbsp("auto"), ast::IsAuto::No => Ok(()), } } } fn repeat(s: &str, n: usize) -> String { iter::repeat(s).take(n).collect() } #[cfg(test)] mod tests { use super::*; use ast; use codemap; use syntax_pos; use with_globals; #[test] fn test_fun_to_string() { with_globals(|| { let abba_ident = ast::Ident::from_str("abba"); let decl = ast::FnDecl { inputs: Vec::new(), output: ast::FunctionRetTy::Default(syntax_pos::DUMMY_SP), variadic: false }; let generics = ast::Generics::default(); assert_eq!( fun_to_string( &decl, ast::FnHeader { unsafety: ast::Unsafety::Normal, constness: codemap::dummy_spanned(ast::Constness::NotConst), asyncness: ast::IsAsync::NotAsync, abi: Abi::Rust, }, abba_ident, &generics ), "fn abba()" ); }) } #[test] fn test_variant_to_string() { with_globals(|| { let ident = ast::Ident::from_str("principal_skinner"); let var = codemap::respan(syntax_pos::DUMMY_SP, ast::Variant_ { ident, attrs: Vec::new(), // making this up as I go.... ? data: ast::VariantData::Unit(ast::DUMMY_NODE_ID), disr_expr: None, }); let varstr = variant_to_string(&var); assert_eq!(varstr, "principal_skinner"); }) } }