--- /dev/null
+use std::cell::{Cell, RefCell};
+use std::rc::Rc;
+
+use rustc_ast::{ast, attr::HasAttrs, token::DelimToken, visit};
+use rustc_span::{symbol, BytePos, Pos, Span, DUMMY_SP};
+
+use crate::attr::*;
+use crate::comment::{contains_comment, rewrite_comment, CodeCharKind, CommentCodeSlices};
+use crate::config::Version;
+use crate::config::{BraceStyle, Config};
+use crate::coverage::transform_missing_snippet;
+use crate::items::{
+ format_impl, format_trait, format_trait_alias, is_mod_decl, is_use_item,
+ rewrite_associated_impl_type, rewrite_extern_crate, rewrite_opaque_impl_type,
+ rewrite_opaque_type, rewrite_type_alias, FnBraceStyle, FnSig, StaticParts, StructParts,
+};
+use crate::macros::{macro_style, rewrite_macro, rewrite_macro_def, MacroPosition};
+use crate::modules::Module;
+use crate::rewrite::{Rewrite, RewriteContext};
+use crate::shape::{Indent, Shape};
+use crate::skip::{is_skip_attr, SkipContext};
+use crate::source_map::{LineRangeUtils, SpanUtils};
+use crate::spanned::Spanned;
+use crate::stmt::Stmt;
+use crate::syntux::session::ParseSess;
+use crate::utils::{
+ self, contains_skip, count_newlines, depr_skip_annotation, format_unsafety, inner_attributes,
+ last_line_width, mk_sp, ptr_vec_to_ref_vec, rewrite_ident, starts_with_newline, stmt_expr,
+};
+use crate::{ErrorKind, FormatReport, FormattingError};
+
+/// Creates a string slice corresponding to the specified span.
+pub(crate) struct SnippetProvider {
+ /// A pointer to the content of the file we are formatting.
+ big_snippet: Rc<String>,
+ /// A position of the start of `big_snippet`, used as an offset.
+ start_pos: usize,
+ /// A end position of the file that this snippet lives.
+ end_pos: usize,
+}
+
+impl SnippetProvider {
+ pub(crate) fn span_to_snippet(&self, span: Span) -> Option<&str> {
+ let start_index = span.lo().to_usize().checked_sub(self.start_pos)?;
+ let end_index = span.hi().to_usize().checked_sub(self.start_pos)?;
+ Some(&self.big_snippet[start_index..end_index])
+ }
+
+ pub(crate) fn new(start_pos: BytePos, end_pos: BytePos, big_snippet: Rc<String>) -> Self {
+ let start_pos = start_pos.to_usize();
+ let end_pos = end_pos.to_usize();
+ SnippetProvider {
+ big_snippet,
+ start_pos,
+ end_pos,
+ }
+ }
+
+ pub(crate) fn entire_snippet(&self) -> &str {
+ self.big_snippet.as_str()
+ }
+
+ pub(crate) fn start_pos(&self) -> BytePos {
+ BytePos::from_usize(self.start_pos)
+ }
+
+ pub(crate) fn end_pos(&self) -> BytePos {
+ BytePos::from_usize(self.end_pos)
+ }
+}
+
+pub(crate) struct FmtVisitor<'a> {
+ parent_context: Option<&'a RewriteContext<'a>>,
+ pub(crate) parse_sess: &'a ParseSess,
+ pub(crate) buffer: String,
+ pub(crate) last_pos: BytePos,
+ // FIXME: use an RAII util or closure for indenting
+ pub(crate) block_indent: Indent,
+ pub(crate) config: &'a Config,
+ pub(crate) is_if_else_block: bool,
+ pub(crate) snippet_provider: &'a SnippetProvider,
+ pub(crate) line_number: usize,
+ /// List of 1-based line ranges which were annotated with skip
+ /// Both bounds are inclusifs.
+ pub(crate) skipped_range: Rc<RefCell<Vec<(usize, usize)>>>,
+ pub(crate) macro_rewrite_failure: bool,
+ pub(crate) report: FormatReport,
+ pub(crate) skip_context: SkipContext,
+ pub(crate) is_macro_def: bool,
+}
+
+impl<'a> Drop for FmtVisitor<'a> {
+ fn drop(&mut self) {
+ if let Some(ctx) = self.parent_context {
+ if self.macro_rewrite_failure {
+ ctx.macro_rewrite_failure.replace(true);
+ }
+ }
+ }
+}
+
+impl<'b, 'a: 'b> FmtVisitor<'a> {
+ fn set_parent_context(&mut self, context: &'a RewriteContext<'_>) {
+ self.parent_context = Some(context);
+ }
+
+ pub(crate) fn shape(&self) -> Shape {
+ Shape::indented(self.block_indent, self.config)
+ }
+
+ fn next_span(&self, hi: BytePos) -> Span {
+ mk_sp(self.last_pos, hi)
+ }
+
+ fn visit_stmt(&mut self, stmt: &Stmt<'_>, include_empty_semi: bool) {
+ debug!(
+ "visit_stmt: {}",
+ self.parse_sess.span_to_debug_info(stmt.span())
+ );
+
+ if stmt.is_empty() {
+ // If the statement is empty, just skip over it. Before that, make sure any comment
+ // snippet preceding the semicolon is picked up.
+ let snippet = self.snippet(mk_sp(self.last_pos, stmt.span().lo()));
+ let original_starts_with_newline = snippet
+ .find(|c| c != ' ')
+ .map_or(false, |i| starts_with_newline(&snippet[i..]));
+ let snippet = snippet.trim();
+ if !snippet.is_empty() {
+ // FIXME(calebcartwright 2021-01-03) - This exists strictly to maintain legacy
+ // formatting where rustfmt would preserve redundant semicolons on Items in a
+ // statement position.
+ // See comment within `walk_stmts` for more info
+ if include_empty_semi {
+ self.format_missing(stmt.span().hi());
+ } else {
+ if original_starts_with_newline {
+ self.push_str("\n");
+ }
+
+ self.push_str(&self.block_indent.to_string(self.config));
+ self.push_str(snippet);
+ }
+ } else if include_empty_semi {
+ self.push_str(";");
+ }
+ self.last_pos = stmt.span().hi();
+ return;
+ }
+
+ match stmt.as_ast_node().kind {
+ ast::StmtKind::Item(ref item) => {
+ self.visit_item(item);
+ self.last_pos = stmt.span().hi();
+ }
+ ast::StmtKind::Local(..) | ast::StmtKind::Expr(..) | ast::StmtKind::Semi(..) => {
+ let attrs = get_attrs_from_stmt(stmt.as_ast_node());
+ if contains_skip(attrs) {
+ self.push_skipped_with_span(
+ attrs,
+ stmt.span(),
+ get_span_without_attrs(stmt.as_ast_node()),
+ );
+ } else {
+ let shape = self.shape();
+ let rewrite = self.with_context(|ctx| stmt.rewrite(&ctx, shape));
+ self.push_rewrite(stmt.span(), rewrite)
+ }
+ }
+ ast::StmtKind::MacCall(ref mac_stmt) => {
+ if self.visit_attrs(&mac_stmt.attrs, ast::AttrStyle::Outer) {
+ self.push_skipped_with_span(
+ &mac_stmt.attrs,
+ stmt.span(),
+ get_span_without_attrs(stmt.as_ast_node()),
+ );
+ } else {
+ self.visit_mac(&mac_stmt.mac, None, MacroPosition::Statement);
+ }
+ self.format_missing(stmt.span().hi());
+ }
+ ast::StmtKind::Empty => (),
+ }
+ }
+
+ /// Remove spaces between the opening brace and the first statement or the inner attribute
+ /// of the block.
+ fn trim_spaces_after_opening_brace(
+ &mut self,
+ b: &ast::Block,
+ inner_attrs: Option<&[ast::Attribute]>,
+ ) {
+ if let Some(first_stmt) = b.stmts.first() {
+ let hi = inner_attrs
+ .and_then(|attrs| inner_attributes(attrs).first().map(|attr| attr.span.lo()))
+ .unwrap_or_else(|| first_stmt.span().lo());
+ let missing_span = self.next_span(hi);
+ let snippet = self.snippet(missing_span);
+ let len = CommentCodeSlices::new(snippet)
+ .nth(0)
+ .and_then(|(kind, _, s)| {
+ if kind == CodeCharKind::Normal {
+ s.rfind('\n')
+ } else {
+ None
+ }
+ });
+ if let Some(len) = len {
+ self.last_pos = self.last_pos + BytePos::from_usize(len);
+ }
+ }
+ }
+
+ pub(crate) fn visit_block(
+ &mut self,
+ b: &ast::Block,
+ inner_attrs: Option<&[ast::Attribute]>,
+ has_braces: bool,
+ ) {
+ debug!(
+ "visit_block: {}",
+ self.parse_sess.span_to_debug_info(b.span),
+ );
+
+ // Check if this block has braces.
+ let brace_compensation = BytePos(if has_braces { 1 } else { 0 });
+
+ self.last_pos = self.last_pos + brace_compensation;
+ self.block_indent = self.block_indent.block_indent(self.config);
+ self.push_str("{");
+ self.trim_spaces_after_opening_brace(b, inner_attrs);
+
+ // Format inner attributes if available.
+ if let Some(attrs) = inner_attrs {
+ self.visit_attrs(attrs, ast::AttrStyle::Inner);
+ }
+
+ self.walk_block_stmts(b);
+
+ if !b.stmts.is_empty() {
+ if let Some(expr) = stmt_expr(&b.stmts[b.stmts.len() - 1]) {
+ if utils::semicolon_for_expr(&self.get_context(), expr) {
+ self.push_str(";");
+ }
+ }
+ }
+
+ let rest_span = self.next_span(b.span.hi());
+ if out_of_file_lines_range!(self, rest_span) {
+ self.push_str(self.snippet(rest_span));
+ self.block_indent = self.block_indent.block_unindent(self.config);
+ } else {
+ // Ignore the closing brace.
+ let missing_span = self.next_span(b.span.hi() - brace_compensation);
+ self.close_block(missing_span, self.unindent_comment_on_closing_brace(b));
+ }
+ self.last_pos = source!(self, b.span).hi();
+ }
+
+ fn close_block(&mut self, span: Span, unindent_comment: bool) {
+ let config = self.config;
+
+ let mut last_hi = span.lo();
+ let mut unindented = false;
+ let mut prev_ends_with_newline = false;
+ let mut extra_newline = false;
+
+ let skip_normal = |s: &str| {
+ let trimmed = s.trim();
+ trimmed.is_empty() || trimmed.chars().all(|c| c == ';')
+ };
+
+ let comment_snippet = self.snippet(span);
+
+ let align_to_right = if unindent_comment && contains_comment(&comment_snippet) {
+ let first_lines = comment_snippet.splitn(2, '/').next().unwrap_or("");
+ last_line_width(first_lines) > last_line_width(&comment_snippet)
+ } else {
+ false
+ };
+
+ for (kind, offset, sub_slice) in CommentCodeSlices::new(comment_snippet) {
+ let sub_slice = transform_missing_snippet(config, sub_slice);
+
+ debug!("close_block: {:?} {:?} {:?}", kind, offset, sub_slice);
+
+ match kind {
+ CodeCharKind::Comment => {
+ if !unindented && unindent_comment && !align_to_right {
+ unindented = true;
+ self.block_indent = self.block_indent.block_unindent(config);
+ }
+ let span_in_between = mk_sp(last_hi, span.lo() + BytePos::from_usize(offset));
+ let snippet_in_between = self.snippet(span_in_between);
+ let mut comment_on_same_line = !snippet_in_between.contains("\n");
+
+ let mut comment_shape =
+ Shape::indented(self.block_indent, config).comment(config);
+ if self.config.version() == Version::Two && comment_on_same_line {
+ self.push_str(" ");
+ // put the first line of the comment on the same line as the
+ // block's last line
+ match sub_slice.find("\n") {
+ None => {
+ self.push_str(&sub_slice);
+ }
+ Some(offset) if offset + 1 == sub_slice.len() => {
+ self.push_str(&sub_slice[..offset]);
+ }
+ Some(offset) => {
+ let first_line = &sub_slice[..offset];
+ self.push_str(first_line);
+ self.push_str(&self.block_indent.to_string_with_newline(config));
+
+ // put the other lines below it, shaping it as needed
+ let other_lines = &sub_slice[offset + 1..];
+ let comment_str =
+ rewrite_comment(other_lines, false, comment_shape, config);
+ match comment_str {
+ Some(ref s) => self.push_str(s),
+ None => self.push_str(other_lines),
+ }
+ }
+ }
+ } else {
+ if comment_on_same_line {
+ // 1 = a space before `//`
+ let offset_len = 1 + last_line_width(&self.buffer)
+ .saturating_sub(self.block_indent.width());
+ match comment_shape
+ .visual_indent(offset_len)
+ .sub_width(offset_len)
+ {
+ Some(shp) => comment_shape = shp,
+ None => comment_on_same_line = false,
+ }
+ };
+
+ if comment_on_same_line {
+ self.push_str(" ");
+ } else {
+ if count_newlines(snippet_in_between) >= 2 || extra_newline {
+ self.push_str("\n");
+ }
+ self.push_str(&self.block_indent.to_string_with_newline(config));
+ }
+
+ let comment_str = rewrite_comment(&sub_slice, false, comment_shape, config);
+ match comment_str {
+ Some(ref s) => self.push_str(s),
+ None => self.push_str(&sub_slice),
+ }
+ }
+ }
+ CodeCharKind::Normal if skip_normal(&sub_slice) => {
+ extra_newline = prev_ends_with_newline && sub_slice.contains('\n');
+ continue;
+ }
+ CodeCharKind::Normal => {
+ self.push_str(&self.block_indent.to_string_with_newline(config));
+ self.push_str(sub_slice.trim());
+ }
+ }
+ prev_ends_with_newline = sub_slice.ends_with('\n');
+ extra_newline = false;
+ last_hi = span.lo() + BytePos::from_usize(offset + sub_slice.len());
+ }
+ if unindented {
+ self.block_indent = self.block_indent.block_indent(self.config);
+ }
+ self.block_indent = self.block_indent.block_unindent(self.config);
+ self.push_str(&self.block_indent.to_string_with_newline(config));
+ self.push_str("}");
+ }
+
+ fn unindent_comment_on_closing_brace(&self, b: &ast::Block) -> bool {
+ self.is_if_else_block && !b.stmts.is_empty()
+ }
+
+ // Note that this only gets called for function definitions. Required methods
+ // on traits do not get handled here.
+ pub(crate) fn visit_fn(
+ &mut self,
+ fk: visit::FnKind<'_>,
+ generics: &ast::Generics,
+ fd: &ast::FnDecl,
+ s: Span,
+ defaultness: ast::Defaultness,
+ inner_attrs: Option<&[ast::Attribute]>,
+ ) {
+ let indent = self.block_indent;
+ let block;
+ let rewrite = match fk {
+ visit::FnKind::Fn(_, ident, _, _, Some(ref b)) => {
+ block = b;
+ self.rewrite_fn_before_block(
+ indent,
+ ident,
+ &FnSig::from_fn_kind(&fk, generics, fd, defaultness),
+ mk_sp(s.lo(), b.span.lo()),
+ )
+ }
+ _ => unreachable!(),
+ };
+
+ if let Some((fn_str, fn_brace_style)) = rewrite {
+ self.format_missing_with_indent(source!(self, s).lo());
+
+ if let Some(rw) = self.single_line_fn(&fn_str, block, inner_attrs) {
+ self.push_str(&rw);
+ self.last_pos = s.hi();
+ return;
+ }
+
+ self.push_str(&fn_str);
+ match fn_brace_style {
+ FnBraceStyle::SameLine => self.push_str(" "),
+ FnBraceStyle::NextLine => {
+ self.push_str(&self.block_indent.to_string_with_newline(self.config))
+ }
+ _ => unreachable!(),
+ }
+ self.last_pos = source!(self, block.span).lo();
+ } else {
+ self.format_missing(source!(self, block.span).lo());
+ }
+
+ self.visit_block(block, inner_attrs, true)
+ }
+
+ pub(crate) fn visit_item(&mut self, item: &ast::Item) {
+ skip_out_of_file_lines_range_visitor!(self, item.span);
+
+ // This is where we bail out if there is a skip attribute. This is only
+ // complex in the module case. It is complex because the module could be
+ // in a separate file and there might be attributes in both files, but
+ // the AST lumps them all together.
+ let filtered_attrs;
+ let mut attrs = &item.attrs;
+ let skip_context_saved = self.skip_context.clone();
+ self.skip_context.update_with_attrs(&attrs);
+
+ let should_visit_node_again = match item.kind {
+ // For use/extern crate items, skip rewriting attributes but check for a skip attribute.
+ ast::ItemKind::Use(..) | ast::ItemKind::ExternCrate(_) => {
+ if contains_skip(attrs) {
+ self.push_skipped_with_span(attrs.as_slice(), item.span(), item.span());
+ false
+ } else {
+ true
+ }
+ }
+ // Module is inline, in this case we treat it like any other item.
+ _ if !is_mod_decl(item) => {
+ if self.visit_attrs(&item.attrs, ast::AttrStyle::Outer) {
+ self.push_skipped_with_span(item.attrs.as_slice(), item.span(), item.span());
+ false
+ } else {
+ true
+ }
+ }
+ // Module is not inline, but should be skipped.
+ ast::ItemKind::Mod(..) if contains_skip(&item.attrs) => false,
+ // Module is not inline and should not be skipped. We want
+ // to process only the attributes in the current file.
+ ast::ItemKind::Mod(..) => {
+ filtered_attrs = filter_inline_attrs(&item.attrs, item.span());
+ // Assert because if we should skip it should be caught by
+ // the above case.
+ assert!(!self.visit_attrs(&filtered_attrs, ast::AttrStyle::Outer));
+ attrs = &filtered_attrs;
+ true
+ }
+ _ => {
+ if self.visit_attrs(&item.attrs, ast::AttrStyle::Outer) {
+ self.push_skipped_with_span(item.attrs.as_slice(), item.span(), item.span());
+ false
+ } else {
+ true
+ }
+ }
+ };
+
+ // TODO(calebcartwright): consider enabling box_patterns feature gate
+ if should_visit_node_again {
+ match item.kind {
+ ast::ItemKind::Use(ref tree) => self.format_import(item, tree),
+ ast::ItemKind::Impl { .. } => {
+ let block_indent = self.block_indent;
+ let rw = self.with_context(|ctx| format_impl(&ctx, item, block_indent));
+ self.push_rewrite(item.span, rw);
+ }
+ ast::ItemKind::Trait(..) => {
+ let block_indent = self.block_indent;
+ let rw = self.with_context(|ctx| format_trait(&ctx, item, block_indent));
+ self.push_rewrite(item.span, rw);
+ }
+ ast::ItemKind::TraitAlias(ref generics, ref generic_bounds) => {
+ let shape = Shape::indented(self.block_indent, self.config);
+ let rw = format_trait_alias(
+ &self.get_context(),
+ item.ident,
+ &item.vis,
+ generics,
+ generic_bounds,
+ shape,
+ );
+ self.push_rewrite(item.span, rw);
+ }
+ ast::ItemKind::ExternCrate(_) => {
+ let rw = rewrite_extern_crate(&self.get_context(), item, self.shape());
+ let span = if attrs.is_empty() {
+ item.span
+ } else {
+ mk_sp(attrs[0].span.lo(), item.span.hi())
+ };
+ self.push_rewrite(span, rw);
+ }
+ ast::ItemKind::Struct(..) | ast::ItemKind::Union(..) => {
+ self.visit_struct(&StructParts::from_item(item));
+ }
+ ast::ItemKind::Enum(ref def, ref generics) => {
+ self.format_missing_with_indent(source!(self, item.span).lo());
+ self.visit_enum(item.ident, &item.vis, def, generics, item.span);
+ self.last_pos = source!(self, item.span).hi();
+ }
+ ast::ItemKind::Mod(ref module) => {
+ let is_inline = !is_mod_decl(item);
+ self.format_missing_with_indent(source!(self, item.span).lo());
+ self.format_mod(module, &item.vis, item.span, item.ident, attrs, is_inline);
+ }
+ ast::ItemKind::MacCall(ref mac) => {
+ self.visit_mac(mac, Some(item.ident), MacroPosition::Item);
+ }
+ ast::ItemKind::ForeignMod(ref foreign_mod) => {
+ self.format_missing_with_indent(source!(self, item.span).lo());
+ self.format_foreign_mod(foreign_mod, item.span);
+ }
+ ast::ItemKind::Static(..) | ast::ItemKind::Const(..) => {
+ self.visit_static(&StaticParts::from_item(item));
+ }
+ ast::ItemKind::Fn(ref fn_kind) => {
+ let ast::FnKind(defaultness, ref fn_signature, ref generics, ref block) =
+ **fn_kind;
+ if let Some(ref body) = block {
+ let inner_attrs = inner_attributes(&item.attrs);
+ let fn_ctxt = match fn_signature.header.ext {
+ ast::Extern::None => visit::FnCtxt::Free,
+ _ => visit::FnCtxt::Foreign,
+ };
+ self.visit_fn(
+ visit::FnKind::Fn(
+ fn_ctxt,
+ item.ident,
+ &fn_signature,
+ &item.vis,
+ Some(body),
+ ),
+ generics,
+ &fn_signature.decl,
+ item.span,
+ defaultness,
+ Some(&inner_attrs),
+ )
+ } else {
+ let indent = self.block_indent;
+ let rewrite = self.rewrite_required_fn(
+ indent,
+ item.ident,
+ &fn_signature,
+ generics,
+ item.span,
+ );
+ self.push_rewrite(item.span, rewrite);
+ }
+ }
+ ast::ItemKind::TyAlias(ref alias_kind) => {
+ let ast::TyAliasKind(_, ref generics, ref generic_bounds, ref ty) =
+ **alias_kind;
+ match ty {
+ Some(ty) => {
+ let rewrite = rewrite_type_alias(
+ item.ident,
+ Some(&*ty),
+ generics,
+ Some(generic_bounds),
+ &self.get_context(),
+ self.block_indent,
+ &item.vis,
+ item.span,
+ );
+ self.push_rewrite(item.span, rewrite);
+ }
+ None => {
+ let rewrite = rewrite_opaque_type(
+ &self.get_context(),
+ self.block_indent,
+ item.ident,
+ generic_bounds,
+ generics,
+ &item.vis,
+ item.span,
+ );
+ self.push_rewrite(item.span, rewrite);
+ }
+ }
+ }
+ ast::ItemKind::GlobalAsm(..) => {
+ let snippet = Some(self.snippet(item.span).to_owned());
+ self.push_rewrite(item.span, snippet);
+ }
+ ast::ItemKind::MacroDef(ref def) => {
+ let rewrite = rewrite_macro_def(
+ &self.get_context(),
+ self.shape(),
+ self.block_indent,
+ def,
+ item.ident,
+ &item.vis,
+ item.span,
+ );
+ self.push_rewrite(item.span, rewrite);
+ }
+ };
+ }
+ self.skip_context = skip_context_saved;
+ }
+
+ pub(crate) fn visit_trait_item(&mut self, ti: &ast::AssocItem) {
+ skip_out_of_file_lines_range_visitor!(self, ti.span);
+
+ if self.visit_attrs(&ti.attrs, ast::AttrStyle::Outer) {
+ self.push_skipped_with_span(ti.attrs.as_slice(), ti.span(), ti.span());
+ return;
+ }
+
+ // TODO(calebcartwright): consider enabling box_patterns feature gate
+ match ti.kind {
+ ast::AssocItemKind::Const(..) => self.visit_static(&StaticParts::from_trait_item(ti)),
+ ast::AssocItemKind::Fn(ref fn_kind) => {
+ let ast::FnKind(defaultness, ref sig, ref generics, ref block) = **fn_kind;
+ if let Some(ref body) = block {
+ let inner_attrs = inner_attributes(&ti.attrs);
+ let vis = ast::Visibility {
+ kind: ast::VisibilityKind::Inherited,
+ span: DUMMY_SP,
+ tokens: None,
+ };
+ let fn_ctxt = visit::FnCtxt::Assoc(visit::AssocCtxt::Trait);
+ self.visit_fn(
+ visit::FnKind::Fn(fn_ctxt, ti.ident, sig, &vis, Some(body)),
+ generics,
+ &sig.decl,
+ ti.span,
+ defaultness,
+ Some(&inner_attrs),
+ );
+ } else {
+ let indent = self.block_indent;
+ let rewrite =
+ self.rewrite_required_fn(indent, ti.ident, sig, generics, ti.span);
+ self.push_rewrite(ti.span, rewrite);
+ }
+ }
+ ast::AssocItemKind::TyAlias(ref ty_alias_kind) => {
+ let ast::TyAliasKind(_, ref generics, ref generic_bounds, ref type_default) =
+ **ty_alias_kind;
+ let rewrite = rewrite_type_alias(
+ ti.ident,
+ type_default.as_ref(),
+ generics,
+ Some(generic_bounds),
+ &self.get_context(),
+ self.block_indent,
+ &ti.vis,
+ ti.span,
+ );
+ self.push_rewrite(ti.span, rewrite);
+ }
+ ast::AssocItemKind::MacCall(ref mac) => {
+ self.visit_mac(mac, Some(ti.ident), MacroPosition::Item);
+ }
+ }
+ }
+
+ pub(crate) fn visit_impl_item(&mut self, ii: &ast::AssocItem) {
+ skip_out_of_file_lines_range_visitor!(self, ii.span);
+
+ if self.visit_attrs(&ii.attrs, ast::AttrStyle::Outer) {
+ self.push_skipped_with_span(ii.attrs.as_slice(), ii.span, ii.span);
+ return;
+ }
+
+ match ii.kind {
+ ast::AssocItemKind::Fn(ref fn_kind) => {
+ let ast::FnKind(defaultness, ref sig, ref generics, ref block) = **fn_kind;
+ if let Some(ref body) = block {
+ let inner_attrs = inner_attributes(&ii.attrs);
+ let fn_ctxt = visit::FnCtxt::Assoc(visit::AssocCtxt::Impl);
+ self.visit_fn(
+ visit::FnKind::Fn(fn_ctxt, ii.ident, sig, &ii.vis, Some(body)),
+ generics,
+ &sig.decl,
+ ii.span,
+ defaultness,
+ Some(&inner_attrs),
+ );
+ } else {
+ let indent = self.block_indent;
+ let rewrite =
+ self.rewrite_required_fn(indent, ii.ident, sig, generics, ii.span);
+ self.push_rewrite(ii.span, rewrite);
+ }
+ }
+ ast::AssocItemKind::Const(..) => self.visit_static(&StaticParts::from_impl_item(ii)),
+ ast::AssocItemKind::TyAlias(ref ty_alias_kind) => {
+ let ast::TyAliasKind(defaultness, ref generics, _, ref ty) = **ty_alias_kind;
+ let rewrite_associated = || {
+ rewrite_associated_impl_type(
+ ii.ident,
+ &ii.vis,
+ defaultness,
+ ty.as_ref(),
+ &generics,
+ &self.get_context(),
+ self.block_indent,
+ ii.span,
+ )
+ };
+ let rewrite = match ty {
+ None => rewrite_associated(),
+ Some(ty) => match ty.kind {
+ ast::TyKind::ImplTrait(_, ref bounds) => rewrite_opaque_impl_type(
+ &self.get_context(),
+ ii.ident,
+ generics,
+ bounds,
+ self.block_indent,
+ ),
+ _ => rewrite_associated(),
+ },
+ };
+ self.push_rewrite(ii.span, rewrite);
+ }
+ ast::AssocItemKind::MacCall(ref mac) => {
+ self.visit_mac(mac, Some(ii.ident), MacroPosition::Item);
+ }
+ }
+ }
+
+ fn visit_mac(&mut self, mac: &ast::MacCall, ident: Option<symbol::Ident>, pos: MacroPosition) {
+ skip_out_of_file_lines_range_visitor!(self, mac.span());
+
+ // 1 = ;
+ let shape = self.shape().saturating_sub_width(1);
+ let rewrite = self.with_context(|ctx| rewrite_macro(mac, ident, ctx, shape, pos));
+ // As of v638 of the rustc-ap-* crates, the associated span no longer includes
+ // the trailing semicolon. This determines the correct span to ensure scenarios
+ // with whitespace between the delimiters and trailing semi (i.e. `foo!(abc) ;`)
+ // are formatted correctly.
+ let (span, rewrite) = match macro_style(mac, &self.get_context()) {
+ DelimToken::Bracket | DelimToken::Paren if MacroPosition::Item == pos => {
+ let search_span = mk_sp(mac.span().hi(), self.snippet_provider.end_pos());
+ let hi = self.snippet_provider.span_before(search_span, ";");
+ let target_span = mk_sp(mac.span().lo(), hi + BytePos(1));
+ let rewrite = rewrite.map(|rw| {
+ if !rw.ends_with(";") {
+ format!("{};", rw)
+ } else {
+ rw
+ }
+ });
+ (target_span, rewrite)
+ }
+ _ => (mac.span(), rewrite),
+ };
+
+ self.push_rewrite(span, rewrite);
+ }
+
+ pub(crate) fn push_str(&mut self, s: &str) {
+ self.line_number += count_newlines(s);
+ self.buffer.push_str(s);
+ }
+
+ #[allow(clippy::needless_pass_by_value)]
+ fn push_rewrite_inner(&mut self, span: Span, rewrite: Option<String>) {
+ if let Some(ref s) = rewrite {
+ self.push_str(s);
+ } else {
+ let snippet = self.snippet(span);
+ self.push_str(snippet.trim());
+ }
+ self.last_pos = source!(self, span).hi();
+ }
+
+ pub(crate) fn push_rewrite(&mut self, span: Span, rewrite: Option<String>) {
+ self.format_missing_with_indent(source!(self, span).lo());
+ self.push_rewrite_inner(span, rewrite);
+ }
+
+ pub(crate) fn push_skipped_with_span(
+ &mut self,
+ attrs: &[ast::Attribute],
+ item_span: Span,
+ main_span: Span,
+ ) {
+ self.format_missing_with_indent(source!(self, item_span).lo());
+ // do not take into account the lines with attributes as part of the skipped range
+ let attrs_end = attrs
+ .iter()
+ .map(|attr| self.parse_sess.line_of_byte_pos(attr.span.hi()))
+ .max()
+ .unwrap_or(1);
+ let first_line = self.parse_sess.line_of_byte_pos(main_span.lo());
+ // Statement can start after some newlines and/or spaces
+ // or it can be on the same line as the last attribute.
+ // So here we need to take a minimum between the two.
+ let lo = std::cmp::min(attrs_end + 1, first_line);
+ self.push_rewrite_inner(item_span, None);
+ let hi = self.line_number + 1;
+ self.skipped_range.borrow_mut().push((lo, hi));
+ }
+
+ pub(crate) fn from_context(ctx: &'a RewriteContext<'_>) -> FmtVisitor<'a> {
+ let mut visitor = FmtVisitor::from_parse_sess(
+ ctx.parse_sess,
+ ctx.config,
+ ctx.snippet_provider,
+ ctx.report.clone(),
+ );
+ visitor.skip_context.update(ctx.skip_context.clone());
+ visitor.set_parent_context(ctx);
+ visitor
+ }
+
+ pub(crate) fn from_parse_sess(
+ parse_session: &'a ParseSess,
+ config: &'a Config,
+ snippet_provider: &'a SnippetProvider,
+ report: FormatReport,
+ ) -> FmtVisitor<'a> {
+ FmtVisitor {
+ parent_context: None,
+ parse_sess: parse_session,
+ buffer: String::with_capacity(snippet_provider.big_snippet.len() * 2),
+ last_pos: BytePos(0),
+ block_indent: Indent::empty(),
+ config,
+ is_if_else_block: false,
+ snippet_provider,
+ line_number: 0,
+ skipped_range: Rc::new(RefCell::new(vec![])),
+ is_macro_def: false,
+ macro_rewrite_failure: false,
+ report,
+ skip_context: Default::default(),
+ }
+ }
+
+ pub(crate) fn opt_snippet(&'b self, span: Span) -> Option<&'a str> {
+ self.snippet_provider.span_to_snippet(span)
+ }
+
+ pub(crate) fn snippet(&'b self, span: Span) -> &'a str {
+ self.opt_snippet(span).unwrap()
+ }
+
+ // Returns true if we should skip the following item.
+ pub(crate) fn visit_attrs(&mut self, attrs: &[ast::Attribute], style: ast::AttrStyle) -> bool {
+ for attr in attrs {
+ if attr.has_name(depr_skip_annotation()) {
+ let file_name = self.parse_sess.span_to_filename(attr.span);
+ self.report.append(
+ file_name,
+ vec![FormattingError::from_span(
+ attr.span,
+ self.parse_sess,
+ ErrorKind::DeprecatedAttr,
+ )],
+ );
+ } else {
+ match &attr.kind {
+ ast::AttrKind::Normal(ref attribute_item, _)
+ if self.is_unknown_rustfmt_attr(&attribute_item.path.segments) =>
+ {
+ let file_name = self.parse_sess.span_to_filename(attr.span);
+ self.report.append(
+ file_name,
+ vec![FormattingError::from_span(
+ attr.span,
+ self.parse_sess,
+ ErrorKind::BadAttr,
+ )],
+ );
+ }
+ _ => (),
+ }
+ }
+ }
+ if contains_skip(attrs) {
+ return true;
+ }
+
+ let attrs: Vec<_> = attrs.iter().filter(|a| a.style == style).cloned().collect();
+ if attrs.is_empty() {
+ return false;
+ }
+
+ let rewrite = attrs.rewrite(&self.get_context(), self.shape());
+ let span = mk_sp(attrs[0].span.lo(), attrs[attrs.len() - 1].span.hi());
+ self.push_rewrite(span, rewrite);
+
+ false
+ }
+
+ fn is_unknown_rustfmt_attr(&self, segments: &[ast::PathSegment]) -> bool {
+ if segments[0].ident.to_string() != "rustfmt" {
+ return false;
+ }
+ !is_skip_attr(segments)
+ }
+
+ fn walk_mod_items(&mut self, m: &ast::Mod) {
+ self.visit_items_with_reordering(&ptr_vec_to_ref_vec(&m.items));
+ }
+
+ fn walk_stmts(&mut self, stmts: &[Stmt<'_>], include_current_empty_semi: bool) {
+ if stmts.is_empty() {
+ return;
+ }
+
+ // Extract leading `use ...;`.
+ let items: Vec<_> = stmts
+ .iter()
+ .take_while(|stmt| stmt.to_item().map_or(false, is_use_item))
+ .filter_map(|stmt| stmt.to_item())
+ .collect();
+
+ if items.is_empty() {
+ self.visit_stmt(&stmts[0], include_current_empty_semi);
+
+ // FIXME(calebcartwright 2021-01-03) - This exists strictly to maintain legacy
+ // formatting where rustfmt would preserve redundant semicolons on Items in a
+ // statement position.
+ //
+ // Starting in rustc-ap-* v692 (~2020-12-01) the rustc parser now parses this as
+ // two separate statements (Item and Empty kinds), whereas before it was parsed as
+ // a single statement with the statement's span including the redundant semicolon.
+ //
+ // rustfmt typically tosses unnecessary/redundant semicolons, and eventually we
+ // should toss these as well, but doing so at this time would
+ // break the Stability Guarantee
+ // N.B. This could be updated to utilize the version gates.
+ let include_next_empty = if stmts.len() > 1 {
+ match (&stmts[0].as_ast_node().kind, &stmts[1].as_ast_node().kind) {
+ (ast::StmtKind::Item(_), ast::StmtKind::Empty) => true,
+ _ => false,
+ }
+ } else {
+ false
+ };
+
+ self.walk_stmts(&stmts[1..], include_next_empty);
+ } else {
+ self.visit_items_with_reordering(&items);
+ self.walk_stmts(&stmts[items.len()..], false);
+ }
+ }
+
+ fn walk_block_stmts(&mut self, b: &ast::Block) {
+ self.walk_stmts(&Stmt::from_ast_nodes(b.stmts.iter()), false)
+ }
+
+ fn format_mod(
+ &mut self,
+ m: &ast::Mod,
+ vis: &ast::Visibility,
+ s: Span,
+ ident: symbol::Ident,
+ attrs: &[ast::Attribute],
+ is_internal: bool,
+ ) {
+ let vis_str = utils::format_visibility(&self.get_context(), vis);
+ self.push_str(&*vis_str);
+ self.push_str(format_unsafety(m.unsafety));
+ self.push_str("mod ");
+ // Calling `to_owned()` to work around borrow checker.
+ let ident_str = rewrite_ident(&self.get_context(), ident).to_owned();
+ self.push_str(&ident_str);
+
+ if is_internal {
+ match self.config.brace_style() {
+ BraceStyle::AlwaysNextLine => {
+ let indent_str = self.block_indent.to_string_with_newline(self.config);
+ self.push_str(&indent_str);
+ self.push_str("{");
+ }
+ _ => self.push_str(" {"),
+ }
+ // Hackery to account for the closing }.
+ let mod_lo = self.snippet_provider.span_after(source!(self, s), "{");
+ let body_snippet =
+ self.snippet(mk_sp(mod_lo, source!(self, m.inner).hi() - BytePos(1)));
+ let body_snippet = body_snippet.trim();
+ if body_snippet.is_empty() {
+ self.push_str("}");
+ } else {
+ self.last_pos = mod_lo;
+ self.block_indent = self.block_indent.block_indent(self.config);
+ self.visit_attrs(attrs, ast::AttrStyle::Inner);
+ self.walk_mod_items(m);
+ let missing_span = self.next_span(m.inner.hi() - BytePos(1));
+ self.close_block(missing_span, false);
+ }
+ self.last_pos = source!(self, m.inner).hi();
+ } else {
+ self.push_str(";");
+ self.last_pos = source!(self, s).hi();
+ }
+ }
+
+ pub(crate) fn format_separate_mod(&mut self, m: &Module<'_>, end_pos: BytePos) {
+ self.block_indent = Indent::empty();
+ if self.visit_attrs(m.attrs(), ast::AttrStyle::Inner) {
+ self.push_skipped_with_span(m.attrs(), m.as_ref().inner, m.as_ref().inner);
+ } else {
+ self.walk_mod_items(m.as_ref());
+ self.format_missing_with_indent(end_pos);
+ }
+ }
+
+ pub(crate) fn skip_empty_lines(&mut self, end_pos: BytePos) {
+ while let Some(pos) = self
+ .snippet_provider
+ .opt_span_after(self.next_span(end_pos), "\n")
+ {
+ if let Some(snippet) = self.opt_snippet(self.next_span(pos)) {
+ if snippet.trim().is_empty() {
+ self.last_pos = pos;
+ } else {
+ return;
+ }
+ }
+ }
+ }
+
+ pub(crate) fn with_context<F>(&mut self, f: F) -> Option<String>
+ where
+ F: Fn(&RewriteContext<'_>) -> Option<String>,
+ {
+ let context = self.get_context();
+ let result = f(&context);
+
+ self.macro_rewrite_failure |= context.macro_rewrite_failure.get();
+ result
+ }
+
+ pub(crate) fn get_context(&self) -> RewriteContext<'_> {
+ RewriteContext {
+ parse_sess: self.parse_sess,
+ config: self.config,
+ inside_macro: Rc::new(Cell::new(false)),
+ use_block: Cell::new(false),
+ is_if_else_block: Cell::new(false),
+ force_one_line_chain: Cell::new(false),
+ snippet_provider: self.snippet_provider,
+ macro_rewrite_failure: Cell::new(false),
+ is_macro_def: self.is_macro_def,
+ report: self.report.clone(),
+ skip_context: self.skip_context.clone(),
+ skipped_range: self.skipped_range.clone(),
+ }
+ }
+}
projects / rustc.git / blobdiff