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::{ast, visit};
  12 use syntax::attr::HasAttrs;
  13 use syntax::codemap::{self, BytePos, CodeMap, Pos, Span};
  14 use syntax::parse::ParseSess;
  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                 )
 272             }
 273             visit::FnKind::Closure(_) => unreachable!(),
 274         };
 275
 276         if let Some(fn_str) = rewrite {
 277             self.format_missing_with_indent(source!(self, s).lo());
 278             self.push_str(&fn_str);
 279             if let Some(c) = fn_str.chars().last() {
 280                 if c == '}' {
 281                     self.last_pos = source!(self, block.span).hi();
 282                     return;
 283                 }
 284             }
 285         } else {
 286             self.format_missing(source!(self, block.span).lo());
 287         }
 288
 289         self.last_pos = source!(self, block.span).lo();
 290         self.visit_block(block, inner_attrs, true)
 291     }
 292
 293     pub fn visit_item(&mut self, item: &ast::Item) {
 294         skip_out_of_file_lines_range_visitor!(self, item.span);
 295
 296         // This is where we bail out if there is a skip attribute. This is only
 297         // complex in the module case. It is complex because the module could be
 298         // in a separate file and there might be attributes in both files, but
 299         // the AST lumps them all together.
 300         let filtered_attrs;
 301         let mut attrs = &item.attrs;
 302         match item.node {
 303             // Module is inline, in this case we treat it like any other item.
 304             _ if !is_mod_decl(item) => {
 305                 if self.visit_attrs(&item.attrs, ast::AttrStyle::Outer) {
 306                     self.push_skipped_with_span(item.span());
 307                     return;
 308                 }
 309             }
 310             // Module is not inline, but should be skipped.
 311             ast::ItemKind::Mod(..) if contains_skip(&item.attrs) => {
 312                 return;
 313             }
 314             // Module is not inline and should not be skipped. We want
 315             // to process only the attributes in the current file.
 316             ast::ItemKind::Mod(..) => {
 317                 filtered_attrs = filter_inline_attrs(&item.attrs, item.span());
 318                 // Assert because if we should skip it should be caught by
 319                 // the above case.
 320                 assert!(!self.visit_attrs(&filtered_attrs, ast::AttrStyle::Outer));
 321                 attrs = &filtered_attrs;
 322             }
 323             _ => {
 324                 if self.visit_attrs(&item.attrs, ast::AttrStyle::Outer) {
 325                     self.push_skipped_with_span(item.span());
 326                     return;
 327                 }
 328             }
 329         }
 330
 331         match item.node {
 332             ast::ItemKind::Use(ref tree) => self.format_import(item, tree),
 333             ast::ItemKind::Impl(..) => {
 334                 let snippet = self.snippet(item.span);
 335                 let where_span_end = snippet
 336                     .find_uncommented("{")
 337                     .map(|x| (BytePos(x as u32)) + source!(self, item.span).lo());
 338                 let rw = format_impl(&self.get_context(), item, self.block_indent, where_span_end);
 339                 self.push_rewrite(item.span, rw);
 340             }
 341             ast::ItemKind::Trait(..) => {
 342                 let rw = format_trait(&self.get_context(), item, self.block_indent);
 343                 self.push_rewrite(item.span, rw);
 344             }
 345             ast::ItemKind::TraitAlias(ref generics, ref ty_param_bounds) => {
 346                 let shape = Shape::indented(self.block_indent, self.config);
 347                 let rw = format_trait_alias(
 348                     &self.get_context(),
 349                     item.ident,
 350                     generics,
 351                     ty_param_bounds,
 352                     shape,
 353                 );
 354                 self.push_rewrite(item.span, rw);
 355             }
 356             ast::ItemKind::ExternCrate(_) => {
 357                 let rw = rewrite_extern_crate(&self.get_context(), item);
 358                 self.push_rewrite(item.span, rw);
 359             }
 360             ast::ItemKind::Struct(..) | ast::ItemKind::Union(..) => {
 361                 self.visit_struct(&StructParts::from_item(item));
 362             }
 363             ast::ItemKind::Enum(ref def, ref generics) => {
 364                 self.format_missing_with_indent(source!(self, item.span).lo());
 365                 self.visit_enum(item.ident, &item.vis, def, generics, item.span);
 366                 self.last_pos = source!(self, item.span).hi();
 367             }
 368             ast::ItemKind::Mod(ref module) => {
 369                 let is_inline = !is_mod_decl(item);
 370                 self.format_missing_with_indent(source!(self, item.span).lo());
 371                 self.format_mod(module, &item.vis, item.span, item.ident, attrs, is_inline);
 372             }
 373             ast::ItemKind::Mac(ref mac) => {
 374                 self.visit_mac(mac, Some(item.ident), MacroPosition::Item);
 375             }
 376             ast::ItemKind::ForeignMod(ref foreign_mod) => {
 377                 self.format_missing_with_indent(source!(self, item.span).lo());
 378                 self.format_foreign_mod(foreign_mod, item.span);
 379             }
 380             ast::ItemKind::Static(..) | ast::ItemKind::Const(..) => {
 381                 self.visit_static(&StaticParts::from_item(item));
 382             }
 383             ast::ItemKind::Fn(ref decl, unsafety, constness, abi, ref generics, ref body) => {
 384                 self.visit_fn(
 385                     visit::FnKind::ItemFn(item.ident, unsafety, constness, abi, &item.vis, body),
 386                     generics,
 387                     decl,
 388                     item.span,
 389                     ast::Defaultness::Final,
 390                     Some(&item.attrs),
 391                 )
 392             }
 393             ast::ItemKind::Ty(ref ty, ref generics) => {
 394                 let rewrite = rewrite_type_alias(
 395                     &self.get_context(),
 396                     self.block_indent,
 397                     item.ident,
 398                     ty,
 399                     generics,
 400                     &item.vis,
 401                     item.span,
 402                 );
 403                 self.push_rewrite(item.span, rewrite);
 404             }
 405             ast::ItemKind::GlobalAsm(..) => {
 406                 let snippet = Some(self.snippet(item.span).to_owned());
 407                 self.push_rewrite(item.span, snippet);
 408             }
 409             ast::ItemKind::MacroDef(ref def) => {
 410                 let rewrite = rewrite_macro_def(
 411                     &self.get_context(),
 412                     self.shape(),
 413                     self.block_indent,
 414                     def,
 415                     item.ident,
 416                     &item.vis,
 417                     item.span,
 418                 );
 419                 self.push_rewrite(item.span, rewrite);
 420             }
 421         }
 422     }
 423
 424     pub fn visit_trait_item(&mut self, ti: &ast::TraitItem) {
 425         skip_out_of_file_lines_range_visitor!(self, ti.span);
 426
 427         if self.visit_attrs(&ti.attrs, ast::AttrStyle::Outer) {
 428             self.push_skipped_with_span(ti.span());
 429             return;
 430         }
 431
 432         match ti.node {
 433             ast::TraitItemKind::Const(..) => self.visit_static(&StaticParts::from_trait_item(ti)),
 434             ast::TraitItemKind::Method(ref sig, None) => {
 435                 let indent = self.block_indent;
 436                 let rewrite =
 437                     self.rewrite_required_fn(indent, ti.ident, sig, &ti.generics, ti.span);
 438                 self.push_rewrite(ti.span, rewrite);
 439             }
 440             ast::TraitItemKind::Method(ref sig, Some(ref body)) => {
 441                 self.visit_fn(
 442                     visit::FnKind::Method(ti.ident, sig, None, body),
 443                     &ti.generics,
 444                     &sig.decl,
 445                     ti.span,
 446                     ast::Defaultness::Final,
 447                     Some(&ti.attrs),
 448                 );
 449             }
 450             ast::TraitItemKind::Type(ref type_param_bounds, ref type_default) => {
 451                 let rewrite = rewrite_associated_type(
 452                     ti.ident,
 453                     type_default.as_ref(),
 454                     Some(type_param_bounds),
 455                     &self.get_context(),
 456                     self.block_indent,
 457                 );
 458                 self.push_rewrite(ti.span, rewrite);
 459             }
 460             ast::TraitItemKind::Macro(ref mac) => {
 461                 self.visit_mac(mac, Some(ti.ident), MacroPosition::Item);
 462             }
 463         }
 464     }
 465
 466     pub fn visit_impl_item(&mut self, ii: &ast::ImplItem) {
 467         skip_out_of_file_lines_range_visitor!(self, ii.span);
 468
 469         if self.visit_attrs(&ii.attrs, ast::AttrStyle::Outer) {
 470             self.push_skipped_with_span(ii.span());
 471             return;
 472         }
 473
 474         match ii.node {
 475             ast::ImplItemKind::Method(ref sig, ref body) => {
 476                 self.visit_fn(
 477                     visit::FnKind::Method(ii.ident, sig, Some(&ii.vis), body),
 478                     &ii.generics,
 479                     &sig.decl,
 480                     ii.span,
 481                     ii.defaultness,
 482                     Some(&ii.attrs),
 483                 );
 484             }
 485             ast::ImplItemKind::Const(..) => self.visit_static(&StaticParts::from_impl_item(ii)),
 486             ast::ImplItemKind::Type(ref ty) => {
 487                 let rewrite = rewrite_associated_impl_type(
 488                     ii.ident,
 489                     ii.defaultness,
 490                     Some(ty),
 491                     None,
 492                     &self.get_context(),
 493                     self.block_indent,
 494                 );
 495                 self.push_rewrite(ii.span, rewrite);
 496             }
 497             ast::ImplItemKind::Macro(ref mac) => {
 498                 self.visit_mac(mac, Some(ii.ident), MacroPosition::Item);
 499             }
 500         }
 501     }
 502
 503     fn visit_mac(&mut self, mac: &ast::Mac, ident: Option<ast::Ident>, pos: MacroPosition) {
 504         skip_out_of_file_lines_range_visitor!(self, mac.span);
 505
 506         // 1 = ;
 507         let shape = self.shape().sub_width(1).unwrap();
 508         let rewrite = rewrite_macro(mac, ident, &self.get_context(), shape, pos);
 509         self.push_rewrite(mac.span, rewrite);
 510     }
 511
 512     pub fn push_str(&mut self, s: &str) {
 513         self.line_number += count_newlines(s);
 514         self.buffer.push_str(s);
 515     }
 516
 517     #[cfg_attr(feature = "cargo-clippy", allow(needless_pass_by_value))]
 518     fn push_rewrite_inner(&mut self, span: Span, rewrite: Option<String>) {
 519         if let Some(ref s) = rewrite {
 520             self.push_str(s);
 521         } else {
 522             let snippet = self.snippet(span);
 523             self.push_str(snippet);
 524         }
 525         self.last_pos = source!(self, span).hi();
 526     }
 527
 528     pub fn push_rewrite(&mut self, span: Span, rewrite: Option<String>) {
 529         self.format_missing_with_indent(source!(self, span).lo());
 530         self.push_rewrite_inner(span, rewrite);
 531     }
 532
 533     pub fn push_skipped_with_span(&mut self, span: Span) {
 534         self.format_missing_with_indent(source!(self, span).lo());
 535         let lo = self.line_number + 1;
 536         self.push_rewrite_inner(span, None);
 537         let hi = self.line_number + 1;
 538         self.skipped_range.push((lo, hi));
 539     }
 540
 541     pub fn from_context(ctx: &'a RewriteContext) -> FmtVisitor<'a> {
 542         FmtVisitor::from_codemap(ctx.parse_session, ctx.config, ctx.snippet_provider)
 543     }
 544
 545     pub fn from_codemap(
 546         parse_session: &'a ParseSess,
 547         config: &'a Config,
 548         snippet_provider: &'a SnippetProvider,
 549     ) -> FmtVisitor<'a> {
 550         FmtVisitor {
 551             parse_session,
 552             codemap: parse_session.codemap(),
 553             buffer: String::with_capacity(snippet_provider.big_snippet.len() * 2),
 554             last_pos: BytePos(0),
 555             block_indent: Indent::empty(),
 556             config,
 557             is_if_else_block: false,
 558             snippet_provider,
 559             line_number: 0,
 560             skipped_range: vec![],
 561         }
 562     }
 563
 564     pub fn opt_snippet(&'b self, span: Span) -> Option<&'a str> {
 565         self.snippet_provider.span_to_snippet(span)
 566     }
 567
 568     pub fn snippet(&'b self, span: Span) -> &'a str {
 569         self.opt_snippet(span).unwrap()
 570     }
 571
 572     // Returns true if we should skip the following item.
 573     pub fn visit_attrs(&mut self, attrs: &[ast::Attribute], style: ast::AttrStyle) -> bool {
 574         if contains_skip(attrs) {
 575             return true;
 576         }
 577
 578         let attrs: Vec<_> = attrs.iter().filter(|a| a.style == style).cloned().collect();
 579         if attrs.is_empty() {
 580             return false;
 581         }
 582
 583         let rewrite = attrs.rewrite(&self.get_context(), self.shape());
 584         let span = mk_sp(attrs[0].span.lo(), attrs[attrs.len() - 1].span.hi());
 585         self.push_rewrite(span, rewrite);
 586
 587         false
 588     }
 589
 590     fn walk_mod_items(&mut self, m: &ast::Mod) {
 591         self.visit_items_with_reordering(&ptr_vec_to_ref_vec(&m.items));
 592     }
 593
 594     fn walk_stmts(&mut self, stmts: &[ast::Stmt]) {
 595         fn to_stmt_item(stmt: &ast::Stmt) -> Option<&ast::Item> {
 596             match stmt.node {
 597                 ast::StmtKind::Item(ref item) => Some(&**item),
 598                 _ => None,
 599             }
 600         }
 601
 602         if stmts.is_empty() {
 603             return;
 604         }
 605
 606         // Extract leading `use ...;`.
 607         let items: Vec<_> = stmts
 608             .iter()
 609             .take_while(|stmt| to_stmt_item(stmt).map_or(false, is_use_item))
 610             .filter_map(|stmt| to_stmt_item(stmt))
 611             .collect();
 612
 613         if items.is_empty() {
 614             self.visit_stmt(&stmts[0]);
 615             self.walk_stmts(&stmts[1..]);
 616         } else {
 617             self.visit_items_with_reordering(&items);
 618             self.walk_stmts(&stmts[items.len()..]);
 619         }
 620     }
 621
 622     fn walk_block_stmts(&mut self, b: &ast::Block) {
 623         self.walk_stmts(&b.stmts)
 624     }
 625
 626     fn format_mod(
 627         &mut self,
 628         m: &ast::Mod,
 629         vis: &ast::Visibility,
 630         s: Span,
 631         ident: ast::Ident,
 632         attrs: &[ast::Attribute],
 633         is_internal: bool,
 634     ) {
 635         self.push_str(&*utils::format_visibility(vis));
 636         self.push_str("mod ");
 637         self.push_str(&ident.to_string());
 638
 639         if is_internal {
 640             match self.config.brace_style() {
 641                 BraceStyle::AlwaysNextLine => {
 642                     let indent_str = self.block_indent.to_string_with_newline(self.config);
 643                     self.push_str(&indent_str);
 644                     self.push_str("{");
 645                 }
 646                 _ => self.push_str(" {"),
 647             }
 648             // Hackery to account for the closing }.
 649             let mod_lo = self.snippet_provider.span_after(source!(self, s), "{");
 650             let body_snippet =
 651                 self.snippet(mk_sp(mod_lo, source!(self, m.inner).hi() - BytePos(1)));
 652             let body_snippet = body_snippet.trim();
 653             if body_snippet.is_empty() {
 654                 self.push_str("}");
 655             } else {
 656                 self.last_pos = mod_lo;
 657                 self.block_indent = self.block_indent.block_indent(self.config);
 658                 self.visit_attrs(attrs, ast::AttrStyle::Inner);
 659                 self.walk_mod_items(m);
 660                 self.format_missing_with_indent(source!(self, m.inner).hi() - BytePos(1));
 661                 self.close_block(false);
 662             }
 663             self.last_pos = source!(self, m.inner).hi();
 664         } else {
 665             self.push_str(";");
 666             self.last_pos = source!(self, s).hi();
 667         }
 668     }
 669
 670     pub fn format_separate_mod(&mut self, m: &ast::Mod, filemap: &codemap::FileMap) {
 671         self.block_indent = Indent::empty();
 672         self.walk_mod_items(m);
 673         self.format_missing_with_indent(filemap.end_pos);
 674     }
 675
 676     pub fn skip_empty_lines(&mut self, end_pos: BytePos) {
 677         while let Some(pos) = self.snippet_provider
 678             .opt_span_after(mk_sp(self.last_pos, end_pos), "\n")
 679         {
 680             if let Some(snippet) = self.opt_snippet(mk_sp(self.last_pos, pos)) {
 681                 if snippet.trim().is_empty() {
 682                     self.last_pos = pos;
 683                 } else {
 684                     return;
 685                 }
 686             }
 687         }
 688     }
 689
 690     pub fn get_context(&self) -> RewriteContext {
 691         RewriteContext {
 692             parse_session: self.parse_session,
 693             codemap: self.codemap,
 694             config: self.config,
 695             inside_macro: false,
 696             use_block: RefCell::new(false),
 697             is_if_else_block: false,
 698             force_one_line_chain: RefCell::new(false),
 699             snippet_provider: self.snippet_provider,
 700         }
 701     }
 702 }