src/visitor.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 use syntax::attr::HasAttrs;
  12 use syntax::codemap::{self, BytePos, CodeMap, Pos, Span};
  13 use syntax::parse::ParseSess;
  14 use syntax::{ast, visit};
  15
  16 use attr::*;
  17 use codemap::{LineRangeUtils, SpanUtils};
  18 use comment::{CodeCharKind, CommentCodeSlices, FindUncommented};
  19 use config::{BraceStyle, Config};
  20 use items::{format_impl, format_trait, format_trait_alias, is_mod_decl, is_use_item,
  21             rewrite_associated_impl_type, rewrite_associated_type, rewrite_extern_crate,
  22             rewrite_type_alias, FnSig, StaticParts, StructParts};
  23 use macros::{rewrite_macro, rewrite_macro_def, MacroPosition};
  24 use rewrite::{Rewrite, RewriteContext};
  25 use shape::{Indent, Shape};
  26 use spanned::Spanned;
  27 use utils::{self, contains_skip, count_newlines, inner_attributes, mk_sp, ptr_vec_to_ref_vec};
  28
  29 use std::cell::RefCell;
  30
  31 /// Creates a string slice corresponding to the specified span.
  32 pub struct SnippetProvider<'a> {
  33     /// A pointer to the content of the file we are formatting.
  34     big_snippet: &'a str,
  35     /// A position of the start of `big_snippet`, used as an offset.
  36     start_pos: usize,
  37 }
  38
  39 impl<'a> SnippetProvider<'a> {
  40     pub fn span_to_snippet(&self, span: Span) -> Option<&str> {
  41         let start_index = span.lo().to_usize().checked_sub(self.start_pos)?;
  42         let end_index = span.hi().to_usize().checked_sub(self.start_pos)?;
  43         Some(&self.big_snippet[start_index..end_index])
  44     }
  45
  46     pub fn new(start_pos: BytePos, big_snippet: &'a str) -> Self {
  47         let start_pos = start_pos.to_usize();
  48         SnippetProvider {
  49             big_snippet,
  50             start_pos,
  51         }
  52     }
  53 }
  54
  55 pub struct FmtVisitor<'a> {
  56     pub parse_session: &'a ParseSess,
  57     pub codemap: &'a CodeMap,
  58     pub buffer: String,
  59     pub last_pos: BytePos,
  60     // FIXME: use an RAII util or closure for indenting
  61     pub block_indent: Indent,
  62     pub config: &'a Config,
  63     pub is_if_else_block: bool,
  64     pub snippet_provider: &'a SnippetProvider<'a>,
  65     pub line_number: usize,
  66     pub skipped_range: Vec<(usize, usize)>,
  67 }
  68
  69 impl<'b, 'a: 'b> FmtVisitor<'a> {
  70     pub fn shape(&self) -> Shape {
  71         Shape::indented(self.block_indent, self.config)
  72     }
  73
  74     fn visit_stmt(&mut self, stmt: &ast::Stmt) {
  75         debug!(
  76             "visit_stmt: {:?} {:?}",
  77             self.codemap.lookup_char_pos(stmt.span.lo()),
  78             self.codemap.lookup_char_pos(stmt.span.hi())
  79         );
  80
  81         match stmt.node {
  82             ast::StmtKind::Item(ref item) => {
  83                 self.visit_item(item);
  84             }
  85             ast::StmtKind::Local(..) | ast::StmtKind::Expr(..) | ast::StmtKind::Semi(..) => {
  86                 if contains_skip(get_attrs_from_stmt(stmt)) {
  87                     self.push_skipped_with_span(stmt.span());
  88                 } else {
  89                     let rewrite = stmt.rewrite(&self.get_context(), self.shape());
  90                     self.push_rewrite(stmt.span(), rewrite)
  91                 }
  92             }
  93             ast::StmtKind::Mac(ref mac) => {
  94                 let (ref mac, _macro_style, ref attrs) = **mac;
  95                 if self.visit_attrs(attrs, ast::AttrStyle::Outer) {
  96                     self.push_skipped_with_span(stmt.span());
  97                 } else {
  98                     self.visit_mac(mac, None, MacroPosition::Statement);
  99                 }
 100                 self.format_missing(stmt.span.hi());
 101             }
 102         }
 103     }
 104
 105     pub fn visit_block(
 106         &mut self,
 107         b: &ast::Block,
 108         inner_attrs: Option<&[ast::Attribute]>,
 109         has_braces: bool,
 110     ) {
 111         debug!(
 112             "visit_block: {:?} {:?}",
 113             self.codemap.lookup_char_pos(b.span.lo()),
 114             self.codemap.lookup_char_pos(b.span.hi())
 115         );
 116
 117         // Check if this block has braces.
 118         let brace_compensation = BytePos(if has_braces { 1 } else { 0 });
 119
 120         self.last_pos = self.last_pos + brace_compensation;
 121         self.block_indent = self.block_indent.block_indent(self.config);
 122         self.push_str("{");
 123
 124         if self.config.remove_blank_lines_at_start_or_end_of_block() {
 125             if let Some(first_stmt) = b.stmts.first() {
 126                 let attr_lo = inner_attrs
 127                     .and_then(|attrs| inner_attributes(attrs).first().map(|attr| attr.span.lo()))
 128                     .or_else(|| {
 129                         // Attributes for an item in a statement position
 130                         // do not belong to the statement. (rust-lang/rust#34459)
 131                         if let ast::StmtKind::Item(ref item) = first_stmt.node {
 132                             item.attrs.first()
 133                         } else {
 134                             first_stmt.attrs().first()
 135                         }.and_then(|attr| {
 136                             // Some stmts can have embedded attributes.
 137                             // e.g. `match { #![attr] ... }`
 138                             let attr_lo = attr.span.lo();
 139                             if attr_lo < first_stmt.span.lo() {
 140                                 Some(attr_lo)
 141                             } else {
 142                                 None
 143                             }
 144                         })
 145                     });
 146
 147                 let snippet = self.snippet(mk_sp(
 148                     self.last_pos,
 149                     attr_lo.unwrap_or_else(|| first_stmt.span.lo()),
 150                 ));
 151                 let len = CommentCodeSlices::new(snippet)
 152                     .nth(0)
 153                     .and_then(|(kind, _, s)| {
 154                         if kind == CodeCharKind::Normal {
 155                             s.rfind('\n')
 156                         } else {
 157                             None
 158                         }
 159                     });
 160                 if let Some(len) = len {
 161                     self.last_pos = self.last_pos + BytePos::from_usize(len);
 162                 }
 163             }
 164         }
 165
 166         // Format inner attributes if available.
 167         let skip_rewrite = if let Some(attrs) = inner_attrs {
 168             self.visit_attrs(attrs, ast::AttrStyle::Inner)
 169         } else {
 170             false
 171         };
 172
 173         if skip_rewrite {
 174             self.push_rewrite(b.span, None);
 175             self.close_block(false);
 176             self.last_pos = source!(self, b.span).hi();
 177             return;
 178         }
 179
 180         self.walk_block_stmts(b);
 181
 182         if !b.stmts.is_empty() {
 183             if let Some(expr) = utils::stmt_expr(&b.stmts[b.stmts.len() - 1]) {
 184                 if utils::semicolon_for_expr(&self.get_context(), expr) {
 185                     self.push_str(";");
 186                 }
 187             }
 188         }
 189
 190         let mut remove_len = BytePos(0);
 191         if self.config.remove_blank_lines_at_start_or_end_of_block() {
 192             if let Some(stmt) = b.stmts.last() {
 193                 let snippet = self.snippet(mk_sp(
 194                     stmt.span.hi(),
 195                     source!(self, b.span).hi() - brace_compensation,
 196                 ));
 197                 let len = CommentCodeSlices::new(snippet)
 198                     .last()
 199                     .and_then(|(kind, _, s)| {
 200                         if kind == CodeCharKind::Normal && s.trim().is_empty() {
 201                             Some(s.len())
 202                         } else {
 203                             None
 204                         }
 205                     });
 206                 if let Some(len) = len {
 207                     remove_len = BytePos::from_usize(len);
 208                 }
 209             }
 210         }
 211
 212         let unindent_comment = (self.is_if_else_block && !b.stmts.is_empty()) && {
 213             let end_pos = source!(self, b.span).hi() - brace_compensation - remove_len;
 214             let snippet = self.snippet(mk_sp(self.last_pos, end_pos));
 215             snippet.contains("//") || snippet.contains("/*")
 216         };
 217         // FIXME: we should compress any newlines here to just one
 218         if unindent_comment {
 219             self.block_indent = self.block_indent.block_unindent(self.config);
 220         }
 221         self.format_missing_with_indent(
 222             source!(self, b.span).hi() - brace_compensation - remove_len,
 223         );
 224         if unindent_comment {
 225             self.block_indent = self.block_indent.block_indent(self.config);
 226         }
 227         self.close_block(unindent_comment);
 228         self.last_pos = source!(self, b.span).hi();
 229     }
 230
 231     // FIXME: this is a terrible hack to indent the comments between the last
 232     // item in the block and the closing brace to the block's level.
 233     // The closing brace itself, however, should be indented at a shallower
 234     // level.
 235     fn close_block(&mut self, unindent_comment: bool) {
 236         let total_len = self.buffer.len();
 237         let chars_too_many = if unindent_comment {
 238             0
 239         } else if self.config.hard_tabs() {
 240             1
 241         } else {
 242             self.config.tab_spaces()
 243         };
 244         self.buffer.truncate(total_len - chars_too_many);
 245         self.push_str("}");
 246         self.block_indent = self.block_indent.block_unindent(self.config);
 247     }
 248
 249     // Note that this only gets called for function definitions. Required methods
 250     // on traits do not get handled here.
 251     fn visit_fn(
 252         &mut self,
 253         fk: visit::FnKind,
 254         generics: &ast::Generics,
 255         fd: &ast::FnDecl,
 256         s: Span,
 257         defaultness: ast::Defaultness,
 258         inner_attrs: Option<&[ast::Attribute]>,
 259     ) {
 260         let indent = self.block_indent;
 261         let block;
 262         let rewrite = match fk {
 263             visit::FnKind::ItemFn(ident, _, _, _, _, b) | visit::FnKind::Method(ident, _, _, b) => {
 264                 block = b;
 265                 self.rewrite_fn(
 266                     indent,
 267                     ident,
 268                     &FnSig::from_fn_kind(&fk, generics, fd, defaultness),
 269                     mk_sp(s.lo(), b.span.lo()),
 270                     b,
 271                     inner_attrs,
 272                 )
 273             }
 274             visit::FnKind::Closure(_) => unreachable!(),
 275         };
 276
 277         if let Some(fn_str) = rewrite {
 278             self.format_missing_with_indent(source!(self, s).lo());
 279             self.push_str(&fn_str);
 280             if let Some(c) = fn_str.chars().last() {
 281                 if c == '}' {
 282                     self.last_pos = source!(self, block.span).hi();
 283                     return;
 284                 }
 285             }
 286         } else {
 287             self.format_missing(source!(self, block.span).lo());
 288         }
 289
 290         self.last_pos = source!(self, block.span).lo();
 291         self.visit_block(block, inner_attrs, true)
 292     }
 293
 294     pub fn visit_item(&mut self, item: &ast::Item) {
 295         skip_out_of_file_lines_range_visitor!(self, item.span);
 296
 297         // This is where we bail out if there is a skip attribute. This is only
 298         // complex in the module case. It is complex because the module could be
 299         // in a separate file and there might be attributes in both files, but
 300         // the AST lumps them all together.
 301         let filtered_attrs;
 302         let mut attrs = &item.attrs;
 303         match item.node {
 304             // Module is inline, in this case we treat it like any other item.
 305             _ if !is_mod_decl(item) => {
 306                 if self.visit_attrs(&item.attrs, ast::AttrStyle::Outer) {
 307                     self.push_skipped_with_span(item.span());
 308                     return;
 309                 }
 310             }
 311             // Module is not inline, but should be skipped.
 312             ast::ItemKind::Mod(..) if contains_skip(&item.attrs) => {
 313                 return;
 314             }
 315             // Module is not inline and should not be skipped. We want
 316             // to process only the attributes in the current file.
 317             ast::ItemKind::Mod(..) => {
 318                 filtered_attrs = filter_inline_attrs(&item.attrs, item.span());
 319                 // Assert because if we should skip it should be caught by
 320                 // the above case.
 321                 assert!(!self.visit_attrs(&filtered_attrs, ast::AttrStyle::Outer));
 322                 attrs = &filtered_attrs;
 323             }
 324             _ => {
 325                 if self.visit_attrs(&item.attrs, ast::AttrStyle::Outer) {
 326                     self.push_skipped_with_span(item.span());
 327                     return;
 328                 }
 329             }
 330         }
 331
 332         match item.node {
 333             ast::ItemKind::Use(ref tree) => self.format_import(item, tree),
 334             ast::ItemKind::Impl(..) => {
 335                 let snippet = self.snippet(item.span);
 336                 let where_span_end = snippet
 337                     .find_uncommented("{")
 338                     .map(|x| (BytePos(x as u32)) + source!(self, item.span).lo());
 339                 let rw = format_impl(&self.get_context(), item, self.block_indent, where_span_end);
 340                 self.push_rewrite(item.span, rw);
 341             }
 342             ast::ItemKind::Trait(..) => {
 343                 let rw = format_trait(&self.get_context(), item, self.block_indent);
 344                 self.push_rewrite(item.span, rw);
 345             }
 346             ast::ItemKind::TraitAlias(ref generics, ref ty_param_bounds) => {
 347                 let shape = Shape::indented(self.block_indent, self.config);
 348                 let rw = format_trait_alias(
 349                     &self.get_context(),
 350                     item.ident,
 351                     generics,
 352                     ty_param_bounds,
 353                     shape,
 354                 );
 355                 self.push_rewrite(item.span, rw);
 356             }
 357             ast::ItemKind::ExternCrate(_) => {
 358                 let rw = rewrite_extern_crate(&self.get_context(), item);
 359                 self.push_rewrite(item.span, rw);
 360             }
 361             ast::ItemKind::Struct(..) | ast::ItemKind::Union(..) => {
 362                 self.visit_struct(&StructParts::from_item(item));
 363             }
 364             ast::ItemKind::Enum(ref def, ref generics) => {
 365                 self.format_missing_with_indent(source!(self, item.span).lo());
 366                 self.visit_enum(item.ident, &item.vis, def, generics, item.span);
 367                 self.last_pos = source!(self, item.span).hi();
 368             }
 369             ast::ItemKind::Mod(ref module) => {
 370                 let is_inline = !is_mod_decl(item);
 371                 self.format_missing_with_indent(source!(self, item.span).lo());
 372                 self.format_mod(module, &item.vis, item.span, item.ident, attrs, is_inline);
 373             }
 374             ast::ItemKind::Mac(ref mac) => {
 375                 self.visit_mac(mac, Some(item.ident), MacroPosition::Item);
 376             }
 377             ast::ItemKind::ForeignMod(ref foreign_mod) => {
 378                 self.format_missing_with_indent(source!(self, item.span).lo());
 379                 self.format_foreign_mod(foreign_mod, item.span);
 380             }
 381             ast::ItemKind::Static(..) | ast::ItemKind::Const(..) => {
 382                 self.visit_static(&StaticParts::from_item(item));
 383             }
 384             ast::ItemKind::Fn(ref decl, unsafety, constness, abi, ref generics, ref body) => {
 385                 let inner_attrs = inner_attributes(&item.attrs);
 386                 self.visit_fn(
 387                     visit::FnKind::ItemFn(item.ident, unsafety, constness, abi, &item.vis, body),
 388                     generics,
 389                     decl,
 390                     item.span,
 391                     ast::Defaultness::Final,
 392                     Some(&inner_attrs),
 393                 )
 394             }
 395             ast::ItemKind::Ty(ref ty, ref generics) => {
 396                 let rewrite = rewrite_type_alias(
 397                     &self.get_context(),
 398                     self.block_indent,
 399                     item.ident,
 400                     ty,
 401                     generics,
 402                     &item.vis,
 403                     item.span,
 404                 );
 405                 self.push_rewrite(item.span, rewrite);
 406             }
 407             ast::ItemKind::GlobalAsm(..) => {
 408                 let snippet = Some(self.snippet(item.span).to_owned());
 409                 self.push_rewrite(item.span, snippet);
 410             }
 411             ast::ItemKind::MacroDef(ref def) => {
 412                 let rewrite = rewrite_macro_def(
 413                     &self.get_context(),
 414                     self.shape(),
 415                     self.block_indent,
 416                     def,
 417                     item.ident,
 418                     &item.vis,
 419                     item.span,
 420                 );
 421                 self.push_rewrite(item.span, rewrite);
 422             }
 423         }
 424     }
 425
 426     pub fn visit_trait_item(&mut self, ti: &ast::TraitItem) {
 427         skip_out_of_file_lines_range_visitor!(self, ti.span);
 428
 429         if self.visit_attrs(&ti.attrs, ast::AttrStyle::Outer) {
 430             self.push_skipped_with_span(ti.span());
 431             return;
 432         }
 433
 434         match ti.node {
 435             ast::TraitItemKind::Const(..) => self.visit_static(&StaticParts::from_trait_item(ti)),
 436             ast::TraitItemKind::Method(ref sig, None) => {
 437                 let indent = self.block_indent;
 438                 let rewrite =
 439                     self.rewrite_required_fn(indent, ti.ident, sig, &ti.generics, ti.span);
 440                 self.push_rewrite(ti.span, rewrite);
 441             }
 442             ast::TraitItemKind::Method(ref sig, Some(ref body)) => {
 443                 let inner_attrs = inner_attributes(&ti.attrs);
 444                 self.visit_fn(
 445                     visit::FnKind::Method(ti.ident, sig, None, body),
 446                     &ti.generics,
 447                     &sig.decl,
 448                     ti.span,
 449                     ast::Defaultness::Final,
 450                     Some(&inner_attrs),
 451                 );
 452             }
 453             ast::TraitItemKind::Type(ref type_param_bounds, ref type_default) => {
 454                 let rewrite = rewrite_associated_type(
 455                     ti.ident,
 456                     type_default.as_ref(),
 457                     Some(type_param_bounds),
 458                     &self.get_context(),
 459                     self.block_indent,
 460                 );
 461                 self.push_rewrite(ti.span, rewrite);
 462             }
 463             ast::TraitItemKind::Macro(ref mac) => {
 464                 self.visit_mac(mac, Some(ti.ident), MacroPosition::Item);
 465             }
 466         }
 467     }
 468
 469     pub fn visit_impl_item(&mut self, ii: &ast::ImplItem) {
 470         skip_out_of_file_lines_range_visitor!(self, ii.span);
 471
 472         if self.visit_attrs(&ii.attrs, ast::AttrStyle::Outer) {
 473             self.push_skipped_with_span(ii.span());
 474             return;
 475         }
 476
 477         match ii.node {
 478             ast::ImplItemKind::Method(ref sig, ref body) => {
 479                 let inner_attrs = inner_attributes(&ii.attrs);
 480                 self.visit_fn(
 481                     visit::FnKind::Method(ii.ident, sig, Some(&ii.vis), body),
 482                     &ii.generics,
 483                     &sig.decl,
 484                     ii.span,
 485                     ii.defaultness,
 486                     Some(&inner_attrs),
 487                 );
 488             }
 489             ast::ImplItemKind::Const(..) => self.visit_static(&StaticParts::from_impl_item(ii)),
 490             ast::ImplItemKind::Type(ref ty) => {
 491                 let rewrite = rewrite_associated_impl_type(
 492                     ii.ident,
 493                     ii.defaultness,
 494                     Some(ty),
 495                     None,
 496                     &self.get_context(),
 497                     self.block_indent,
 498                 );
 499                 self.push_rewrite(ii.span, rewrite);
 500             }
 501             ast::ImplItemKind::Macro(ref mac) => {
 502                 self.visit_mac(mac, Some(ii.ident), MacroPosition::Item);
 503             }
 504         }
 505     }
 506
 507     fn visit_mac(&mut self, mac: &ast::Mac, ident: Option<ast::Ident>, pos: MacroPosition) {
 508         skip_out_of_file_lines_range_visitor!(self, mac.span);
 509
 510         // 1 = ;
 511         let shape = self.shape().sub_width(1).unwrap();
 512         let rewrite = rewrite_macro(mac, ident, &self.get_context(), shape, pos);
 513         self.push_rewrite(mac.span, rewrite);
 514     }
 515
 516     pub fn push_str(&mut self, s: &str) {
 517         self.line_number += count_newlines(s);
 518         self.buffer.push_str(s);
 519     }
 520
 521     #[cfg_attr(feature = "cargo-clippy", allow(needless_pass_by_value))]
 522     fn push_rewrite_inner(&mut self, span: Span, rewrite: Option<String>) {
 523         if let Some(ref s) = rewrite {
 524             self.push_str(s);
 525         } else {
 526             let snippet = self.snippet(span);
 527             self.push_str(snippet);
 528         }
 529         self.last_pos = source!(self, span).hi();
 530     }
 531
 532     pub fn push_rewrite(&mut self, span: Span, rewrite: Option<String>) {
 533         self.format_missing_with_indent(source!(self, span).lo());
 534         self.push_rewrite_inner(span, rewrite);
 535     }
 536
 537     pub fn push_skipped_with_span(&mut self, span: Span) {
 538         self.format_missing_with_indent(source!(self, span).lo());
 539         let lo = self.line_number + 1;
 540         self.push_rewrite_inner(span, None);
 541         let hi = self.line_number + 1;
 542         self.skipped_range.push((lo, hi));
 543     }
 544
 545     pub fn from_context(ctx: &'a RewriteContext) -> FmtVisitor<'a> {
 546         FmtVisitor::from_codemap(ctx.parse_session, ctx.config, ctx.snippet_provider)
 547     }
 548
 549     pub fn from_codemap(
 550         parse_session: &'a ParseSess,
 551         config: &'a Config,
 552         snippet_provider: &'a SnippetProvider,
 553     ) -> FmtVisitor<'a> {
 554         FmtVisitor {
 555             parse_session,
 556             codemap: parse_session.codemap(),
 557             buffer: String::with_capacity(snippet_provider.big_snippet.len() * 2),
 558             last_pos: BytePos(0),
 559             block_indent: Indent::empty(),
 560             config,
 561             is_if_else_block: false,
 562             snippet_provider,
 563             line_number: 0,
 564             skipped_range: vec![],
 565         }
 566     }
 567
 568     pub fn opt_snippet(&'b self, span: Span) -> Option<&'a str> {
 569         self.snippet_provider.span_to_snippet(span)
 570     }
 571
 572     pub fn snippet(&'b self, span: Span) -> &'a str {
 573         self.opt_snippet(span).unwrap()
 574     }
 575
 576     // Returns true if we should skip the following item.
 577     pub fn visit_attrs(&mut self, attrs: &[ast::Attribute], style: ast::AttrStyle) -> bool {
 578         if contains_skip(attrs) {
 579             return true;
 580         }
 581
 582         let attrs: Vec<_> = attrs.iter().filter(|a| a.style == style).cloned().collect();
 583         if attrs.is_empty() {
 584             return false;
 585         }
 586
 587         let rewrite = attrs.rewrite(&self.get_context(), self.shape());
 588         let span = mk_sp(attrs[0].span.lo(), attrs[attrs.len() - 1].span.hi());
 589         self.push_rewrite(span, rewrite);
 590
 591         false
 592     }
 593
 594     fn walk_mod_items(&mut self, m: &ast::Mod) {
 595         self.visit_items_with_reordering(&ptr_vec_to_ref_vec(&m.items));
 596     }
 597
 598     fn walk_stmts(&mut self, stmts: &[ast::Stmt]) {
 599         fn to_stmt_item(stmt: &ast::Stmt) -> Option<&ast::Item> {
 600             match stmt.node {
 601                 ast::StmtKind::Item(ref item) => Some(&**item),
 602                 _ => None,
 603             }
 604         }
 605
 606         if stmts.is_empty() {
 607             return;
 608         }
 609
 610         // Extract leading `use ...;`.
 611         let items: Vec<_> = stmts
 612             .iter()
 613             .take_while(|stmt| to_stmt_item(stmt).map_or(false, is_use_item))
 614             .filter_map(|stmt| to_stmt_item(stmt))
 615             .collect();
 616
 617         if items.is_empty() {
 618             self.visit_stmt(&stmts[0]);
 619             self.walk_stmts(&stmts[1..]);
 620         } else {
 621             self.visit_items_with_reordering(&items);
 622             self.walk_stmts(&stmts[items.len()..]);
 623         }
 624     }
 625
 626     fn walk_block_stmts(&mut self, b: &ast::Block) {
 627         self.walk_stmts(&b.stmts)
 628     }
 629
 630     fn format_mod(
 631         &mut self,
 632         m: &ast::Mod,
 633         vis: &ast::Visibility,
 634         s: Span,
 635         ident: ast::Ident,
 636         attrs: &[ast::Attribute],
 637         is_internal: bool,
 638     ) {
 639         self.push_str(&*utils::format_visibility(vis));
 640         self.push_str("mod ");
 641         self.push_str(&ident.to_string());
 642
 643         if is_internal {
 644             match self.config.brace_style() {
 645                 BraceStyle::AlwaysNextLine => {
 646                     let indent_str = self.block_indent.to_string_with_newline(self.config);
 647                     self.push_str(&indent_str);
 648                     self.push_str("{");
 649                 }
 650                 _ => self.push_str(" {"),
 651             }
 652             // Hackery to account for the closing }.
 653             let mod_lo = self.snippet_provider.span_after(source!(self, s), "{");
 654             let body_snippet =
 655                 self.snippet(mk_sp(mod_lo, source!(self, m.inner).hi() - BytePos(1)));
 656             let body_snippet = body_snippet.trim();
 657             if body_snippet.is_empty() {
 658                 self.push_str("}");
 659             } else {
 660                 self.last_pos = mod_lo;
 661                 self.block_indent = self.block_indent.block_indent(self.config);
 662                 self.visit_attrs(attrs, ast::AttrStyle::Inner);
 663                 self.walk_mod_items(m);
 664                 self.format_missing_with_indent(source!(self, m.inner).hi() - BytePos(1));
 665                 self.close_block(false);
 666             }
 667             self.last_pos = source!(self, m.inner).hi();
 668         } else {
 669             self.push_str(";");
 670             self.last_pos = source!(self, s).hi();
 671         }
 672     }
 673
 674     pub fn format_separate_mod(&mut self, m: &ast::Mod, filemap: &codemap::FileMap) {
 675         self.block_indent = Indent::empty();
 676         self.walk_mod_items(m);
 677         self.format_missing_with_indent(filemap.end_pos);
 678     }
 679
 680     pub fn skip_empty_lines(&mut self, end_pos: BytePos) {
 681         while let Some(pos) = self.snippet_provider
 682             .opt_span_after(mk_sp(self.last_pos, end_pos), "\n")
 683         {
 684             if let Some(snippet) = self.opt_snippet(mk_sp(self.last_pos, pos)) {
 685                 if snippet.trim().is_empty() {
 686                     self.last_pos = pos;
 687                 } else {
 688                     return;
 689                 }
 690             }
 691         }
 692     }
 693
 694     pub fn get_context(&self) -> RewriteContext {
 695         RewriteContext {
 696             parse_session: self.parse_session,
 697             codemap: self.codemap,
 698             config: self.config,
 699             inside_macro: false,
 700             use_block: RefCell::new(false),
 701             is_if_else_block: false,
 702             force_one_line_chain: RefCell::new(false),
 703             snippet_provider: self.snippet_provider,
 704         }
 705     }
 706 }