src/items.rs

   1 // Copyright 2015 The Rust Project Developers. See the COPYRIGHT
   2 // file at the top-level directory of this distribution and at
   3 // http://rust-lang.org/COPYRIGHT.
   4 //
   5 // Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
   6 // http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
   7 // <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
   8 // option. This file may not be copied, modified, or distributed
   9 // except according to those terms.
  10
  11 // Formatting top-level items - functions, structs, enums, traits, impls.
  12
  13 use {ReturnIndent, BraceStyle};
  14 use utils::make_indent;
  15 use lists::{write_list, ListFormatting, SeparatorTactic, ListTactic};
  16 use visitor::FmtVisitor;
  17 use syntax::{ast, abi};
  18 use syntax::codemap::{self, Span, BytePos};
  19 use syntax::print::pprust;
  20 use syntax::parse::token;
  21
  22 impl<'a> FmtVisitor<'a> {
  23     pub fn rewrite_fn(&mut self,
  24                       indent: usize,
  25                       ident: ast::Ident,
  26                       fd: &ast::FnDecl,
  27                       explicit_self: Option<&ast::ExplicitSelf>,
  28                       generics: &ast::Generics,
  29                       unsafety: &ast::Unsafety,
  30                       abi: &abi::Abi,
  31                       vis: ast::Visibility,
  32                       span_end: BytePos)
  33         -> String
  34     {
  35         let newline_brace = self.newline_for_brace(&generics.where_clause);
  36
  37         let mut result = self.rewrite_fn_base(indent,
  38                                               ident,
  39                                               fd,
  40                                               explicit_self,
  41                                               generics,
  42                                               unsafety,
  43                                               abi,
  44                                               vis,
  45                                               span_end,
  46                                               newline_brace);
  47
  48         // Prepare for the function body by possibly adding a newline and indent.
  49         // FIXME we'll miss anything between the end of the signature and the start
  50         // of the body, but we need more spans from the compiler to solve this.
  51         if newline_brace {
  52             result.push('\n');
  53             result.push_str(&make_indent(indent));
  54         } else {
  55             result.push(' ');
  56         }
  57
  58         result
  59     }
  60
  61     pub fn rewrite_required_fn(&mut self,
  62                                indent: usize,
  63                                ident: ast::Ident,
  64                                sig: &ast::MethodSig,
  65                                span: Span)
  66         -> String
  67     {
  68         // Drop semicolon or it will be interpreted as comment
  69         let span_end = span.hi - BytePos(1);
  70
  71         let mut result = self.rewrite_fn_base(indent,
  72                                               ident,
  73                                               &sig.decl,
  74                                               Some(&sig.explicit_self),
  75                                               &sig.generics,
  76                                               &sig.unsafety,
  77                                               &sig.abi,
  78                                               ast::Visibility::Inherited,
  79                                               span_end,
  80                                               false);
  81
  82         // Re-attach semicolon
  83         result.push(';');
  84
  85         result
  86     }
  87
  88     fn rewrite_fn_base(&mut self,
  89                        indent: usize,
  90                        ident: ast::Ident,
  91                        fd: &ast::FnDecl,
  92                        explicit_self: Option<&ast::ExplicitSelf>,
  93                        generics: &ast::Generics,
  94                        unsafety: &ast::Unsafety,
  95                        abi: &abi::Abi,
  96                        vis: ast::Visibility,
  97                        span_end: BytePos,
  98                        newline_brace: bool)
  99         -> String
 100     {
 101         // FIXME we'll lose any comments in between parts of the function decl, but anyone
 102         // who comments there probably deserves what they get.
 103
 104         let where_clause = &generics.where_clause;
 105
 106         let mut result = String::with_capacity(1024);
 107         // Vis unsafety abi.
 108         if vis == ast::Visibility::Public {
 109             result.push_str("pub ");
 110         }
 111         if let &ast::Unsafety::Unsafe = unsafety {
 112             result.push_str("unsafe ");
 113         }
 114         if *abi != abi::Rust {
 115             result.push_str("extern ");
 116             result.push_str(&abi.to_string());
 117             result.push(' ');
 118         }
 119
 120         // fn foo
 121         result.push_str("fn ");
 122         result.push_str(&token::get_ident(ident));
 123
 124         // Generics.
 125         let generics_indent = indent + result.len();
 126         result.push_str(&self.rewrite_generics(generics,
 127                                                generics_indent,
 128                                                span_for_return(&fd.output).lo));
 129
 130         let ret_str = self.rewrite_return(&fd.output);
 131
 132         // Args.
 133         let (one_line_budget, multi_line_budget, arg_indent) =
 134             self.compute_budgets_for_args(&mut result, indent, ret_str.len(), newline_brace);
 135
 136         debug!("rewrite_fn: one_line_budget: {}, multi_line_budget: {}, arg_indent: {}",
 137                one_line_budget, multi_line_budget, arg_indent);
 138
 139         result.push('(');
 140         result.push_str(&self.rewrite_args(&fd.inputs,
 141                                            explicit_self,
 142                                            one_line_budget,
 143                                            multi_line_budget,
 144                                            arg_indent,
 145                                            span_for_return(&fd.output)));
 146         result.push(')');
 147
 148         // Return type.
 149         if ret_str.len() > 0 {
 150             // If we've already gone multi-line, or the return type would push
 151             // over the max width, then put the return type on a new line.
 152             if result.contains("\n") ||
 153                result.len() + indent + ret_str.len() > config!(max_width) {
 154                 let indent = match config!(fn_return_indent) {
 155                     ReturnIndent::WithWhereClause => indent + 4,
 156                     // TODO we might want to check that using the arg indent doesn't
 157                     // blow our budget, and if it does, then fallback to the where
 158                     // clause indent.
 159                     _ => arg_indent,
 160                 };
 161
 162                 result.push('\n');
 163                 result.push_str(&make_indent(indent));
 164             } else {
 165                 result.push(' ');
 166             }
 167             result.push_str(&ret_str);
 168
 169             // Comment between return type and the end of the decl.
 170             let snippet_lo = fd.output.span().hi;
 171             if where_clause.predicates.len() == 0 {
 172                 let snippet_hi = span_end;
 173                 let snippet = self.snippet(codemap::mk_sp(snippet_lo, snippet_hi));
 174                 let snippet = snippet.trim();
 175                 if snippet.len() > 0 {
 176                     result.push(' ');
 177                     result.push_str(snippet);
 178                 }
 179             } else {
 180                 // FIXME it would be nice to catch comments between the return type
 181                 // and the where clause, but we don't have a span for the where
 182                 // clause.
 183             }
 184         }
 185
 186         // Where clause.
 187         result.push_str(&self.rewrite_where_clause(where_clause, indent, span_end));
 188
 189         result
 190     }
 191
 192     fn rewrite_args(&self,
 193                     args: &[ast::Arg],
 194                     explicit_self: Option<&ast::ExplicitSelf>,
 195                     one_line_budget: usize,
 196                     multi_line_budget: usize,
 197                     arg_indent: usize,
 198                     ret_span: Span)
 199         -> String
 200     {
 201         let mut arg_item_strs: Vec<_> = args.iter().map(|a| self.rewrite_fn_input(a)).collect();
 202         // Account for sugary self.
 203         let mut min_args = 1;
 204         if let Some(explicit_self) = explicit_self {
 205             match explicit_self.node {
 206                 ast::ExplicitSelf_::SelfRegion(ref lt, ref m, _) => {
 207                     let lt_str = match lt {
 208                         &Some(ref l) => format!("{} ", pprust::lifetime_to_string(l)),
 209                         &None => String::new(),
 210                     };
 211                     let mut_str = match m {
 212                         &ast::Mutability::MutMutable => "mut ".to_owned(),
 213                         &ast::Mutability::MutImmutable => String::new(),
 214                     };
 215                     arg_item_strs[0] = format!("&{}{}self", lt_str, mut_str);
 216                     min_args = 2;
 217                 }
 218                 ast::ExplicitSelf_::SelfExplicit(ref ty, _) => {
 219                     arg_item_strs[0] = format!("self: {}", pprust::ty_to_string(ty));
 220                 }
 221                 ast::ExplicitSelf_::SelfValue(_) => {
 222                     assert!(args.len() >= 1, "&[ast::Arg] shouldn't be empty.");
 223
 224                     // this hacky solution caused by absence of `Mutability` in `SelfValue`.
 225                     let mut_str = {
 226                         if let ast::Pat_::PatIdent(ast::BindingMode::BindByValue(mutability), _, _)
 227                                 = args[0].pat.node {
 228                             match mutability {
 229                                 ast::Mutability::MutMutable => "mut ",
 230                                 ast::Mutability::MutImmutable => "",
 231                             }
 232                         } else {
 233                             panic!("there is a bug or change in structure of AST, aborting.");
 234                         }
 235                     };
 236
 237                     arg_item_strs[0] = format!("{}self", mut_str);
 238                     min_args = 2;
 239                 }
 240                 _ => {}
 241             }
 242         }
 243
 244         // Comments between args
 245         let mut arg_comments = Vec::new();
 246         if min_args == 2 {
 247             arg_comments.push("".to_owned());
 248         }
 249         // TODO if there are no args, there might still be a comment, but without
 250         // spans for the comment or parens, there is no chance of getting it right.
 251         // You also don't get to put a comment on self, unless it is explicit.
 252         if args.len() >= min_args {
 253             arg_comments = self.make_comments_for_list(arg_comments,
 254                                                        args[min_args-1..].iter(),
 255                                                        ",",
 256                                                        ")",
 257                                                        |arg| arg.pat.span.lo,
 258                                                        |arg| arg.ty.span.hi,
 259                                                        ret_span.lo);
 260         }
 261
 262         debug!("comments: {:?}", arg_comments);
 263
 264         // If there are // comments, keep them multi-line.
 265         let mut list_tactic = ListTactic::HorizontalVertical;
 266         if arg_comments.iter().any(|c| c.contains("//")) {
 267             list_tactic = ListTactic::Vertical;
 268         }
 269
 270         assert_eq!(arg_item_strs.len(), arg_comments.len());
 271         let arg_strs: Vec<_> = arg_item_strs.into_iter().zip(arg_comments.into_iter()).collect();
 272
 273         let fmt = ListFormatting {
 274             tactic: list_tactic,
 275             separator: ",",
 276             trailing_separator: SeparatorTactic::Never,
 277             indent: arg_indent,
 278             h_width: one_line_budget,
 279             v_width: multi_line_budget,
 280         };
 281
 282         write_list(&arg_strs, &fmt)
 283     }
 284
 285     // Gets comments in between items of a list.
 286     fn make_comments_for_list<T, I, F1, F2>(&self,
 287                                             prefix: Vec<String>,
 288                                             mut it: I,
 289                                             separator: &str,
 290                                             terminator: &str,
 291                                             get_lo: F1,
 292                                             get_hi: F2,
 293                                             next_span_start: BytePos)
 294         -> Vec<String>
 295         where I: Iterator<Item=T>,
 296               F1: Fn(&T) -> BytePos,
 297               F2: Fn(&T) -> BytePos
 298     {
 299         let mut result = prefix;
 300
 301         let mut prev_end = get_hi(&it.next().unwrap());
 302         for item in it {
 303             let cur_start = get_lo(&item);
 304             let snippet = self.snippet(codemap::mk_sp(prev_end, cur_start));
 305             let mut snippet = snippet.trim();
 306             let white_space: &[_] = &[' ', '\t'];
 307             if snippet.starts_with(separator) {
 308                 snippet = snippet[separator.len()..].trim_matches(white_space);
 309             } else if snippet.ends_with(separator) {
 310                 snippet = snippet[..snippet.len()-separator.len()].trim_matches(white_space);
 311             }
 312             result.push(snippet.to_owned());
 313             prev_end = get_hi(&item);
 314         }
 315         // Get the last commment.
 316         // FIXME If you thought the crap with the commas was ugly, just wait.
 317         // This is awful. We're going to look from the last item span to the
 318         // start of the return type span, then we drop everything after the
 319         // first closing paren. Obviously, this will break if there is a
 320         // closing paren in the comment.
 321         // The fix is comments in the AST or a span for the closing paren.
 322         let snippet = self.snippet(codemap::mk_sp(prev_end, next_span_start));
 323         let snippet = snippet.trim();
 324         let snippet = &snippet[..snippet.find(terminator)
 325                                     .unwrap_or(snippet.find(separator).unwrap_or(snippet.len()))];
 326         let snippet = snippet.trim();
 327         result.push(snippet.to_owned());
 328
 329         result
 330     }
 331
 332     fn compute_budgets_for_args(&self,
 333                                 result: &mut String,
 334                                 indent: usize,
 335                                 ret_str_len: usize,
 336                                 newline_brace: bool)
 337         -> (usize, usize, usize)
 338     {
 339         let mut budgets = None;
 340
 341         // Try keeping everything on the same line
 342         if !result.contains("\n") {
 343             // 3 = `() `, space is before ret_string
 344             let mut used_space = indent + result.len() + ret_str_len + 3;
 345             if !newline_brace {
 346                 used_space += 2;
 347             }
 348             let one_line_budget = if used_space > config!(max_width) {
 349                 0
 350             } else {
 351                 config!(max_width) - used_space
 352             };
 353
 354             // 2 = `()`
 355             let used_space = indent + result.len() + 2;
 356             let max_space = config!(ideal_width) + config!(leeway);
 357             debug!("compute_budgets_for_args: used_space: {}, max_space: {}",
 358                    used_space, max_space);
 359             if used_space < max_space {
 360                 budgets = Some((one_line_budget,
 361                                 max_space - used_space,
 362                                 indent + result.len() + 1));
 363             }
 364         }
 365
 366         // Didn't work. we must force vertical layout and put args on a newline.
 367         if let None = budgets {
 368             result.push('\n');
 369             result.push_str(&make_indent(indent + 4));
 370             // 6 = new indent + `()`
 371             let used_space = indent + 6;
 372             let max_space = config!(ideal_width) + config!(leeway);
 373             if used_space > max_space {
 374                 // Whoops! bankrupt.
 375                 // TODO take evasive action, perhaps kill the indent or something.
 376             } else {
 377                 // 5 = new indent + `(`
 378                 budgets = Some((0, max_space - used_space, indent + 5));
 379             }
 380         }
 381
 382         budgets.unwrap()
 383     }
 384
 385     fn newline_for_brace(&self, where_clause: &ast::WhereClause) -> bool {
 386         match config!(fn_brace_style) {
 387             BraceStyle::AlwaysNextLine => true,
 388             BraceStyle::SameLineWhere if where_clause.predicates.len() > 0 => true,
 389             _ => false,
 390         }
 391     }
 392
 393     pub fn visit_struct(&mut self,
 394                         ident: ast::Ident,
 395                         vis: ast::Visibility,
 396                         struct_def: &ast::StructDef,
 397                         generics: &ast::Generics,
 398                         span: Span)
 399     {
 400         let header_str = self.struct_header(ident, vis);
 401         self.changes.push_str_span(span, &header_str);
 402
 403         if struct_def.fields.len() == 0 {
 404             assert!(generics.where_clause.predicates.len() == 0,
 405                     "No-field struct with where clause?");
 406             assert!(generics.lifetimes.len() == 0, "No-field struct with generics?");
 407             assert!(generics.ty_params.len() == 0, "No-field struct with generics?");
 408
 409             self.changes.push_str_span(span, ";");
 410             return;
 411         }
 412
 413         let mut generics_buf = String::new();
 414         let generics_str = self.rewrite_generics(generics, self.block_indent, struct_def.fields[0].span.lo);
 415         generics_buf.push_str(&generics_str);
 416
 417         if generics.where_clause.predicates.len() > 0 {
 418             generics_buf.push_str(&self.rewrite_where_clause(&generics.where_clause,
 419                                                              self.block_indent,
 420                                                              struct_def.fields[0].span.lo));
 421             generics_buf.push_str(&make_indent(self.block_indent));
 422             generics_buf.push_str("\n{");
 423
 424         } else {
 425             generics_buf.push_str(" {");
 426         }
 427         self.changes.push_str_span(span, &generics_buf);
 428
 429         let struct_snippet = self.snippet(span);
 430         // FIXME this will give incorrect results if there is a { in a commet.
 431         self.last_pos = span.lo + BytePos(struct_snippet.find('{').unwrap() as u32 + 1);
 432
 433         self.block_indent += config!(tab_spaces);
 434         for (i, f) in struct_def.fields.iter().enumerate() {
 435             self.visit_field(f, i == struct_def.fields.len() - 1, span.lo, &struct_snippet);
 436         }
 437         self.block_indent -= config!(tab_spaces);
 438
 439         self.format_missing_with_indent(span.lo + BytePos(struct_snippet.rfind('}').unwrap() as u32));
 440         self.changes.push_str_span(span, "}");
 441     }
 442
 443     fn struct_header(&self,
 444                      ident: ast::Ident,
 445                      vis: ast::Visibility)
 446         -> String
 447     {
 448         let vis = if vis == ast::Visibility::Public {
 449             "pub "
 450         } else {
 451             ""
 452         };
 453
 454         format!("{}struct {}", vis, &token::get_ident(ident))
 455     }
 456
 457     // Field of a struct
 458     fn visit_field(&mut self,
 459                    field: &ast::StructField,
 460                    last_field: bool,
 461                    // These two args are for missing spans hacks.
 462                    struct_start: BytePos,
 463                    struct_snippet: &str)
 464     {
 465         if self.visit_attrs(&field.node.attrs) {
 466             return;
 467         }
 468         self.format_missing_with_indent(field.span.lo);
 469
 470         let name = match field.node.kind {
 471             ast::StructFieldKind::NamedField(ident, _) => Some(token::get_ident(ident)),
 472             ast::StructFieldKind::UnnamedField(_) => None,
 473         };
 474         let vis = match field.node.kind {
 475             ast::StructFieldKind::NamedField(_, vis) |
 476             ast::StructFieldKind::UnnamedField(vis) => if vis == ast::Visibility::Public {
 477                 "pub "
 478             } else {
 479                 ""
 480             }
 481         };
 482         let typ = pprust::ty_to_string(&field.node.ty);
 483
 484         let mut field_str = match name {
 485             Some(name) => {
 486                 let budget = config!(ideal_width) - self.block_indent;
 487                 // 3 is being conservative and assuming that there will be a trailing comma.
 488                 if self.block_indent + vis.len() + name.len() + typ.len() + 3 > budget {
 489                     format!("{}{}:\n{}{}",
 490                             vis,
 491                             name,
 492                             &make_indent(self.block_indent + config!(tab_spaces)),
 493                             typ)
 494                 } else {
 495                     format!("{}{}: {}", vis, name, typ)
 496                 }
 497             }
 498             None => format!("{}{}", vis, typ),
 499         };
 500         if !last_field || config!(struct_trailing_comma) {
 501             field_str.push(',');
 502         }
 503         self.changes.push_str_span(field.span, &field_str);
 504
 505         // This hack makes sure we only add comments etc. after the comma, and
 506         // makes sure we don't repeat any commas.
 507         let hi = field.span.hi;
 508         // FIXME a comma in a comment will break this hack.
 509         let comma_pos = match struct_snippet[(hi.0 - struct_start.0) as usize..].find(',') {
 510             Some(i) => i,
 511             None => 0,
 512         };
 513         self.last_pos = hi + BytePos(comma_pos as u32 + 1);
 514     }
 515
 516     fn rewrite_generics(&self, generics: &ast::Generics, indent: usize, span_end: BytePos) -> String {
 517         // FIXME convert bounds to where clauses where they get too big or if
 518         // there is a where clause at all.
 519         let mut result = String::new();
 520         let lifetimes: &[_] = &generics.lifetimes;
 521         let tys: &[_] = &generics.ty_params;
 522         if lifetimes.len() + tys.len() == 0 {
 523             return result;
 524         }
 525
 526         let budget = config!(max_width) - indent - 2;
 527         // TODO might need to insert a newline if the generics are really long
 528         result.push('<');
 529
 530         // Strings for the generics.
 531         let lt_strs = lifetimes.iter().map(|l| self.rewrite_lifetime_def(l));
 532         let ty_strs = tys.iter().map(|ty| self.rewrite_ty_param(ty));
 533
 534         // Extract comments between generics.
 535         let lt_spans = lifetimes.iter().map(|l| {
 536             let hi = if l.bounds.len() == 0 {
 537                 l.lifetime.span.hi
 538             } else {
 539                 l.bounds[l.bounds.len() - 1].span.hi
 540             };
 541             codemap::mk_sp(l.lifetime.span.lo, hi)
 542         });
 543         let ty_spans = tys.iter().map(span_for_ty_param);
 544         let comments = self.make_comments_for_list(Vec::new(),
 545                                                    lt_spans.chain(ty_spans),
 546                                                    ",",
 547                                                    ">",
 548                                                    |sp| sp.lo,
 549                                                    |sp| sp.hi,
 550                                                    span_end);
 551
 552         // If there are // comments, keep them multi-line.
 553         let mut list_tactic = ListTactic::HorizontalVertical;
 554         if comments.iter().any(|c| c.contains("//")) {
 555             list_tactic = ListTactic::Vertical;
 556         }
 557
 558         let generics_strs: Vec<_> = lt_strs.chain(ty_strs).zip(comments.into_iter()).collect();
 559         let fmt = ListFormatting {
 560             tactic: list_tactic,
 561             separator: ",",
 562             trailing_separator: SeparatorTactic::Never,
 563             indent: indent + 1,
 564             h_width: budget,
 565             v_width: budget,
 566         };
 567         result.push_str(&write_list(&generics_strs, &fmt));
 568
 569         result.push('>');
 570
 571         result
 572     }
 573
 574     fn rewrite_where_clause(&self,
 575                             where_clause: &ast::WhereClause,
 576                             indent: usize,
 577                             span_end: BytePos)
 578         -> String
 579     {
 580         let mut result = String::new();
 581         if where_clause.predicates.len() == 0 {
 582             return result;
 583         }
 584
 585         result.push('\n');
 586         result.push_str(&make_indent(indent + 4));
 587         result.push_str("where ");
 588
 589         let comments = self.make_comments_for_list(Vec::new(),
 590                                                    where_clause.predicates.iter(),
 591                                                    ",",
 592                                                    "{",
 593                                                    |pred| span_for_where_pred(pred).lo,
 594                                                    |pred| span_for_where_pred(pred).hi,
 595                                                    span_end);
 596
 597         let where_strs: Vec<_> = where_clause.predicates.iter()
 598                                                         .map(|p| (self.rewrite_pred(p)))
 599                                                         .zip(comments.into_iter())
 600                                                         .collect();
 601
 602         let budget = config!(ideal_width) + config!(leeway) - indent - 10;
 603         let fmt = ListFormatting {
 604             tactic: ListTactic::Vertical,
 605             separator: ",",
 606             trailing_separator: SeparatorTactic::Never,
 607             indent: indent + 10,
 608             h_width: budget,
 609             v_width: budget,
 610         };
 611         result.push_str(&write_list(&where_strs, &fmt));
 612
 613         result
 614     }
 615
 616     fn rewrite_return(&self, ret: &ast::FunctionRetTy) -> String {
 617         match *ret {
 618             ast::FunctionRetTy::DefaultReturn(_) => String::new(),
 619             ast::FunctionRetTy::NoReturn(_) => "-> !".to_owned(),
 620             ast::FunctionRetTy::Return(ref ty) => "-> ".to_owned() + &pprust::ty_to_string(ty),
 621         }
 622     }
 623
 624     // TODO we farm this out, but this could spill over the column limit, so we ought to handle it properly
 625     fn rewrite_fn_input(&self, arg: &ast::Arg) -> String {
 626         format!("{}: {}",
 627                 pprust::pat_to_string(&arg.pat),
 628                 pprust::ty_to_string(&arg.ty))
 629     }
 630 }
 631
 632 fn span_for_return(ret: &ast::FunctionRetTy) -> Span {
 633     match *ret {
 634         ast::FunctionRetTy::NoReturn(ref span) |
 635         ast::FunctionRetTy::DefaultReturn(ref span) => span.clone(),
 636         ast::FunctionRetTy::Return(ref ty) => ty.span,
 637     }
 638 }
 639
 640 fn span_for_ty_param(ty: &ast::TyParam) -> Span {
 641     // Note that ty.span is the span for ty.ident, not the whole item.
 642     let lo = ty.span.lo;
 643     if let Some(ref def) = ty.default {
 644         return codemap::mk_sp(lo, def.span.hi);
 645     }
 646     if ty.bounds.len() == 0 {
 647         return ty.span;
 648     }
 649     let hi = match ty.bounds[ty.bounds.len() - 1] {
 650         ast::TyParamBound::TraitTyParamBound(ref ptr, _) => ptr.span.hi,
 651         ast::TyParamBound::RegionTyParamBound(ref l) => l.span.hi,
 652     };
 653     codemap::mk_sp(lo, hi)
 654 }
 655
 656 fn span_for_where_pred(pred: &ast::WherePredicate) -> Span {
 657     match *pred {
 658         ast::WherePredicate::BoundPredicate(ref p) => p.span,
 659         ast::WherePredicate::RegionPredicate(ref p) => p.span,
 660         ast::WherePredicate::EqPredicate(ref p) => p.span,
 661     }
 662 }