--- /dev/null
+// Format list-like macro invocations. These are invocations whose token trees
+// can be interpreted as expressions and separated by commas.
+// Note that these token trees do not actually have to be interpreted as
+// expressions by the compiler. An example of an invocation we would reformat is
+// foo!( x, y, z ). The token x may represent an identifier in the code, but we
+// interpreted as an expression.
+// Macro uses which are not-list like, such as bar!(key => val), will not be
+// reformatted.
+// List-like invocations with parentheses will be formatted as function calls,
+// and those with brackets will be formatted as array literals.
+
+use std::collections::HashMap;
+use std::panic::{catch_unwind, AssertUnwindSafe};
+
+use rustc_ast::token::{BinOpToken, DelimToken, Token, TokenKind};
+use rustc_ast::tokenstream::{Cursor, LazyTokenStream, TokenStream, TokenTree};
+use rustc_ast::{ast, ptr};
+use rustc_ast_pretty::pprust;
+use rustc_parse::parser::{ForceCollect, Parser};
+use rustc_parse::{stream_to_parser, MACRO_ARGUMENTS};
+use rustc_span::{
+ symbol::{self, kw},
+ BytePos, Span, Symbol, DUMMY_SP,
+};
+
+use crate::comment::{
+ contains_comment, CharClasses, FindUncommented, FullCodeCharKind, LineClasses,
+};
+use crate::config::lists::*;
+use crate::expr::rewrite_array;
+use crate::lists::{itemize_list, write_list, ListFormatting};
+use crate::overflow;
+use crate::rewrite::{Rewrite, RewriteContext};
+use crate::shape::{Indent, Shape};
+use crate::source_map::SpanUtils;
+use crate::spanned::Spanned;
+use crate::utils::{
+ format_visibility, indent_next_line, is_empty_line, mk_sp, remove_trailing_white_spaces,
+ rewrite_ident, trim_left_preserve_layout, wrap_str, NodeIdExt,
+};
+use crate::visitor::FmtVisitor;
+
+const FORCED_BRACKET_MACROS: &[&str] = &["vec!"];
+
+#[derive(Debug, Clone, Copy, PartialEq, Eq)]
+pub(crate) enum MacroPosition {
+ Item,
+ Statement,
+ Expression,
+ Pat,
+}
+
+#[derive(Debug)]
+pub(crate) enum MacroArg {
+ Expr(ptr::P<ast::Expr>),
+ Ty(ptr::P<ast::Ty>),
+ Pat(ptr::P<ast::Pat>),
+ Item(ptr::P<ast::Item>),
+ Keyword(symbol::Ident, Span),
+}
+
+impl MacroArg {
+ fn is_item(&self) -> bool {
+ match self {
+ MacroArg::Item(..) => true,
+ _ => false,
+ }
+ }
+}
+
+impl Rewrite for ast::Item {
+ fn rewrite(&self, context: &RewriteContext<'_>, shape: Shape) -> Option<String> {
+ let mut visitor = crate::visitor::FmtVisitor::from_context(context);
+ visitor.block_indent = shape.indent;
+ visitor.last_pos = self.span().lo();
+ visitor.visit_item(self);
+ Some(visitor.buffer.to_owned())
+ }
+}
+
+impl Rewrite for MacroArg {
+ fn rewrite(&self, context: &RewriteContext<'_>, shape: Shape) -> Option<String> {
+ match *self {
+ MacroArg::Expr(ref expr) => expr.rewrite(context, shape),
+ MacroArg::Ty(ref ty) => ty.rewrite(context, shape),
+ MacroArg::Pat(ref pat) => pat.rewrite(context, shape),
+ MacroArg::Item(ref item) => item.rewrite(context, shape),
+ MacroArg::Keyword(ident, _) => Some(ident.name.to_string()),
+ }
+ }
+}
+
+fn build_parser<'a>(context: &RewriteContext<'a>, cursor: Cursor) -> Parser<'a> {
+ stream_to_parser(
+ context.parse_sess.inner(),
+ cursor.collect(),
+ MACRO_ARGUMENTS,
+ )
+}
+
+fn parse_macro_arg<'a, 'b: 'a>(parser: &'a mut Parser<'b>) -> Option<MacroArg> {
+ macro_rules! parse_macro_arg {
+ ($macro_arg:ident, $parser:expr, $f:expr) => {
+ let mut cloned_parser = (*parser).clone();
+ match $parser(&mut cloned_parser) {
+ Ok(x) => {
+ if parser.sess.span_diagnostic.has_errors() {
+ parser.sess.span_diagnostic.reset_err_count();
+ } else {
+ // Parsing succeeded.
+ *parser = cloned_parser;
+ return Some(MacroArg::$macro_arg($f(x)?));
+ }
+ }
+ Err(mut e) => {
+ e.cancel();
+ parser.sess.span_diagnostic.reset_err_count();
+ }
+ }
+ };
+ }
+
+ parse_macro_arg!(
+ Expr,
+ |parser: &mut rustc_parse::parser::Parser<'b>| parser.parse_expr(),
+ |x: ptr::P<ast::Expr>| Some(x)
+ );
+ parse_macro_arg!(
+ Ty,
+ |parser: &mut rustc_parse::parser::Parser<'b>| parser.parse_ty(),
+ |x: ptr::P<ast::Ty>| Some(x)
+ );
+ parse_macro_arg!(
+ Pat,
+ |parser: &mut rustc_parse::parser::Parser<'b>| parser.parse_pat(None),
+ |x: ptr::P<ast::Pat>| Some(x)
+ );
+ // `parse_item` returns `Option<ptr::P<ast::Item>>`.
+ parse_macro_arg!(
+ Item,
+ |parser: &mut rustc_parse::parser::Parser<'b>| parser.parse_item(ForceCollect::No),
+ |x: Option<ptr::P<ast::Item>>| x
+ );
+
+ None
+}
+
+/// Rewrite macro name without using pretty-printer if possible.
+fn rewrite_macro_name(
+ context: &RewriteContext<'_>,
+ path: &ast::Path,
+ extra_ident: Option<symbol::Ident>,
+) -> String {
+ let name = if path.segments.len() == 1 {
+ // Avoid using pretty-printer in the common case.
+ format!("{}!", rewrite_ident(context, path.segments[0].ident))
+ } else {
+ format!("{}!", pprust::path_to_string(path))
+ };
+ match extra_ident {
+ Some(ident) if ident.name != kw::Empty => format!("{} {}", name, ident),
+ _ => name,
+ }
+}
+
+// Use this on failing to format the macro call.
+fn return_macro_parse_failure_fallback(
+ context: &RewriteContext<'_>,
+ indent: Indent,
+ span: Span,
+) -> Option<String> {
+ // Mark this as a failure however we format it
+ context.macro_rewrite_failure.replace(true);
+
+ // Heuristically determine whether the last line of the macro uses "Block" style
+ // rather than using "Visual" style, or another indentation style.
+ let is_like_block_indent_style = context
+ .snippet(span)
+ .lines()
+ .last()
+ .map(|closing_line| {
+ closing_line.trim().chars().all(|ch| match ch {
+ '}' | ')' | ']' => true,
+ _ => false,
+ })
+ })
+ .unwrap_or(false);
+ if is_like_block_indent_style {
+ return trim_left_preserve_layout(context.snippet(span), indent, &context.config);
+ }
+
+ context.skipped_range.borrow_mut().push((
+ context.parse_sess.line_of_byte_pos(span.lo()),
+ context.parse_sess.line_of_byte_pos(span.hi()),
+ ));
+
+ // Return the snippet unmodified if the macro is not block-like
+ Some(context.snippet(span).to_owned())
+}
+
+pub(crate) fn rewrite_macro(
+ mac: &ast::MacCall,
+ extra_ident: Option<symbol::Ident>,
+ context: &RewriteContext<'_>,
+ shape: Shape,
+ position: MacroPosition,
+) -> Option<String> {
+ let should_skip = context
+ .skip_context
+ .skip_macro(&context.snippet(mac.path.span).to_owned());
+ if should_skip {
+ None
+ } else {
+ let guard = context.enter_macro();
+ let result = catch_unwind(AssertUnwindSafe(|| {
+ rewrite_macro_inner(
+ mac,
+ extra_ident,
+ context,
+ shape,
+ position,
+ guard.is_nested(),
+ )
+ }));
+ match result {
+ Err(..) | Ok(None) => {
+ context.macro_rewrite_failure.replace(true);
+ None
+ }
+ Ok(rw) => rw,
+ }
+ }
+}
+
+fn check_keyword<'a, 'b: 'a>(parser: &'a mut Parser<'b>) -> Option<MacroArg> {
+ for &keyword in RUST_KW.iter() {
+ if parser.token.is_keyword(keyword)
+ && parser.look_ahead(1, |t| {
+ t.kind == TokenKind::Eof
+ || t.kind == TokenKind::Comma
+ || t.kind == TokenKind::CloseDelim(DelimToken::NoDelim)
+ })
+ {
+ parser.bump();
+ return Some(MacroArg::Keyword(
+ symbol::Ident::with_dummy_span(keyword),
+ parser.prev_token.span,
+ ));
+ }
+ }
+ None
+}
+
+fn rewrite_macro_inner(
+ mac: &ast::MacCall,
+ extra_ident: Option<symbol::Ident>,
+ context: &RewriteContext<'_>,
+ shape: Shape,
+ position: MacroPosition,
+ is_nested_macro: bool,
+) -> Option<String> {
+ if context.config.use_try_shorthand() {
+ if let Some(expr) = convert_try_mac(mac, context) {
+ context.leave_macro();
+ return expr.rewrite(context, shape);
+ }
+ }
+
+ let original_style = macro_style(mac, context);
+
+ let macro_name = rewrite_macro_name(context, &mac.path, extra_ident);
+
+ let style = if FORCED_BRACKET_MACROS.contains(&¯o_name[..]) && !is_nested_macro {
+ DelimToken::Bracket
+ } else {
+ original_style
+ };
+
+ let ts = mac.args.inner_tokens();
+ let has_comment = contains_comment(context.snippet(mac.span()));
+ if ts.is_empty() && !has_comment {
+ return match style {
+ DelimToken::Paren if position == MacroPosition::Item => {
+ Some(format!("{}();", macro_name))
+ }
+ DelimToken::Bracket if position == MacroPosition::Item => {
+ Some(format!("{}[];", macro_name))
+ }
+ DelimToken::Paren => Some(format!("{}()", macro_name)),
+ DelimToken::Bracket => Some(format!("{}[]", macro_name)),
+ DelimToken::Brace => Some(format!("{} {{}}", macro_name)),
+ _ => unreachable!(),
+ };
+ }
+ // Format well-known macros which cannot be parsed as a valid AST.
+ if macro_name == "lazy_static!" && !has_comment {
+ if let success @ Some(..) = format_lazy_static(context, shape, &ts) {
+ return success;
+ }
+ }
+
+ let mut parser = build_parser(context, ts.trees());
+ let mut arg_vec = Vec::new();
+ let mut vec_with_semi = false;
+ let mut trailing_comma = false;
+
+ if DelimToken::Brace != style {
+ loop {
+ if let Some(arg) = check_keyword(&mut parser) {
+ arg_vec.push(arg);
+ } else if let Some(arg) = parse_macro_arg(&mut parser) {
+ arg_vec.push(arg);
+ } else {
+ return return_macro_parse_failure_fallback(context, shape.indent, mac.span());
+ }
+
+ match parser.token.kind {
+ TokenKind::Eof => break,
+ TokenKind::Comma => (),
+ TokenKind::Semi => {
+ // Try to parse `vec![expr; expr]`
+ if FORCED_BRACKET_MACROS.contains(&¯o_name[..]) {
+ parser.bump();
+ if parser.token.kind != TokenKind::Eof {
+ match parse_macro_arg(&mut parser) {
+ Some(arg) => {
+ arg_vec.push(arg);
+ parser.bump();
+ if parser.token.kind == TokenKind::Eof && arg_vec.len() == 2 {
+ vec_with_semi = true;
+ break;
+ }
+ }
+ None => {
+ return return_macro_parse_failure_fallback(
+ context,
+ shape.indent,
+ mac.span(),
+ );
+ }
+ }
+ }
+ }
+ return return_macro_parse_failure_fallback(context, shape.indent, mac.span());
+ }
+ _ if arg_vec.last().map_or(false, MacroArg::is_item) => continue,
+ _ => return return_macro_parse_failure_fallback(context, shape.indent, mac.span()),
+ }
+
+ parser.bump();
+
+ if parser.token.kind == TokenKind::Eof {
+ trailing_comma = true;
+ break;
+ }
+ }
+ }
+
+ if !arg_vec.is_empty() && arg_vec.iter().all(MacroArg::is_item) {
+ return rewrite_macro_with_items(
+ context,
+ &arg_vec,
+ ¯o_name,
+ shape,
+ style,
+ position,
+ mac.span(),
+ );
+ }
+
+ match style {
+ DelimToken::Paren => {
+ // Handle special case: `vec!(expr; expr)`
+ if vec_with_semi {
+ handle_vec_semi(context, shape, arg_vec, macro_name, style)
+ } else {
+ // Format macro invocation as function call, preserve the trailing
+ // comma because not all macros support them.
+ overflow::rewrite_with_parens(
+ context,
+ ¯o_name,
+ arg_vec.iter(),
+ shape,
+ mac.span(),
+ context.config.width_heuristics().fn_call_width,
+ if trailing_comma {
+ Some(SeparatorTactic::Always)
+ } else {
+ Some(SeparatorTactic::Never)
+ },
+ )
+ .map(|rw| match position {
+ MacroPosition::Item => format!("{};", rw),
+ _ => rw,
+ })
+ }
+ }
+ DelimToken::Bracket => {
+ // Handle special case: `vec![expr; expr]`
+ if vec_with_semi {
+ handle_vec_semi(context, shape, arg_vec, macro_name, style)
+ } else {
+ // If we are rewriting `vec!` macro or other special macros,
+ // then we can rewrite this as an usual array literal.
+ // Otherwise, we must preserve the original existence of trailing comma.
+ let macro_name = ¯o_name.as_str();
+ let mut force_trailing_comma = if trailing_comma {
+ Some(SeparatorTactic::Always)
+ } else {
+ Some(SeparatorTactic::Never)
+ };
+ if FORCED_BRACKET_MACROS.contains(macro_name) && !is_nested_macro {
+ context.leave_macro();
+ if context.use_block_indent() {
+ force_trailing_comma = Some(SeparatorTactic::Vertical);
+ };
+ }
+ let rewrite = rewrite_array(
+ macro_name,
+ arg_vec.iter(),
+ mac.span(),
+ context,
+ shape,
+ force_trailing_comma,
+ Some(original_style),
+ )?;
+ let comma = match position {
+ MacroPosition::Item => ";",
+ _ => "",
+ };
+
+ Some(format!("{}{}", rewrite, comma))
+ }
+ }
+ DelimToken::Brace => {
+ // For macro invocations with braces, always put a space between
+ // the `macro_name!` and `{ /* macro_body */ }` but skip modifying
+ // anything in between the braces (for now).
+ let snippet = context.snippet(mac.span()).trim_start_matches(|c| c != '{');
+ match trim_left_preserve_layout(snippet, shape.indent, &context.config) {
+ Some(macro_body) => Some(format!("{} {}", macro_name, macro_body)),
+ None => Some(format!("{} {}", macro_name, snippet)),
+ }
+ }
+ _ => unreachable!(),
+ }
+}
+
+fn handle_vec_semi(
+ context: &RewriteContext<'_>,
+ shape: Shape,
+ arg_vec: Vec<MacroArg>,
+ macro_name: String,
+ delim_token: DelimToken,
+) -> Option<String> {
+ let (left, right) = match delim_token {
+ DelimToken::Paren => ("(", ")"),
+ DelimToken::Bracket => ("[", "]"),
+ _ => unreachable!(),
+ };
+
+ let mac_shape = shape.offset_left(macro_name.len())?;
+ // 8 = `vec![]` + `; ` or `vec!()` + `; `
+ let total_overhead = 8;
+ let nested_shape = mac_shape.block_indent(context.config.tab_spaces());
+ let lhs = arg_vec[0].rewrite(context, nested_shape)?;
+ let rhs = arg_vec[1].rewrite(context, nested_shape)?;
+ if !lhs.contains('\n')
+ && !rhs.contains('\n')
+ && lhs.len() + rhs.len() + total_overhead <= shape.width
+ {
+ // macro_name(lhs; rhs) or macro_name[lhs; rhs]
+ Some(format!("{}{}{}; {}{}", macro_name, left, lhs, rhs, right))
+ } else {
+ // macro_name(\nlhs;\nrhs\n) or macro_name[\nlhs;\nrhs\n]
+ Some(format!(
+ "{}{}{}{};{}{}{}{}",
+ macro_name,
+ left,
+ nested_shape.indent.to_string_with_newline(context.config),
+ lhs,
+ nested_shape.indent.to_string_with_newline(context.config),
+ rhs,
+ shape.indent.to_string_with_newline(context.config),
+ right
+ ))
+ }
+}
+
+pub(crate) fn rewrite_macro_def(
+ context: &RewriteContext<'_>,
+ shape: Shape,
+ indent: Indent,
+ def: &ast::MacroDef,
+ ident: symbol::Ident,
+ vis: &ast::Visibility,
+ span: Span,
+) -> Option<String> {
+ let snippet = Some(remove_trailing_white_spaces(context.snippet(span)));
+ if snippet.as_ref().map_or(true, |s| s.ends_with(';')) {
+ return snippet;
+ }
+
+ let ts = def.body.inner_tokens();
+ let mut parser = MacroParser::new(ts.into_trees());
+ let parsed_def = match parser.parse() {
+ Some(def) => def,
+ None => return snippet,
+ };
+
+ let mut result = if def.macro_rules {
+ String::from("macro_rules!")
+ } else {
+ format!("{}macro", format_visibility(context, vis))
+ };
+
+ result += " ";
+ result += rewrite_ident(context, ident);
+
+ let multi_branch_style = def.macro_rules || parsed_def.branches.len() != 1;
+
+ let arm_shape = if multi_branch_style {
+ shape
+ .block_indent(context.config.tab_spaces())
+ .with_max_width(context.config)
+ } else {
+ shape
+ };
+
+ let branch_items = itemize_list(
+ context.snippet_provider,
+ parsed_def.branches.iter(),
+ "}",
+ ";",
+ |branch| branch.span.lo(),
+ |branch| branch.span.hi(),
+ |branch| match branch.rewrite(context, arm_shape, multi_branch_style) {
+ Some(v) => Some(v),
+ // if the rewrite returned None because a macro could not be rewritten, then return the
+ // original body
+ None if context.macro_rewrite_failure.get() => {
+ Some(context.snippet(branch.body).trim().to_string())
+ }
+ None => None,
+ },
+ context.snippet_provider.span_after(span, "{"),
+ span.hi(),
+ false,
+ )
+ .collect::<Vec<_>>();
+
+ let fmt = ListFormatting::new(arm_shape, context.config)
+ .separator(if def.macro_rules { ";" } else { "" })
+ .trailing_separator(SeparatorTactic::Always)
+ .preserve_newline(true);
+
+ if multi_branch_style {
+ result += " {";
+ result += &arm_shape.indent.to_string_with_newline(context.config);
+ }
+
+ match write_list(&branch_items, &fmt) {
+ Some(ref s) => result += s,
+ None => return snippet,
+ }
+
+ if multi_branch_style {
+ result += &indent.to_string_with_newline(context.config);
+ result += "}";
+ }
+
+ Some(result)
+}
+
+fn register_metavariable(
+ map: &mut HashMap<String, String>,
+ result: &mut String,
+ name: &str,
+ dollar_count: usize,
+) {
+ let mut new_name = "$".repeat(dollar_count - 1);
+ let mut old_name = "$".repeat(dollar_count);
+
+ new_name.push('z');
+ new_name.push_str(name);
+ old_name.push_str(name);
+
+ result.push_str(&new_name);
+ map.insert(old_name, new_name);
+}
+
+// Replaces `$foo` with `zfoo`. We must check for name overlap to ensure we
+// aren't causing problems.
+// This should also work for escaped `$` variables, where we leave earlier `$`s.
+fn replace_names(input: &str) -> Option<(String, HashMap<String, String>)> {
+ // Each substitution will require five or six extra bytes.
+ let mut result = String::with_capacity(input.len() + 64);
+ let mut substs = HashMap::new();
+ let mut dollar_count = 0;
+ let mut cur_name = String::new();
+
+ for (kind, c) in CharClasses::new(input.chars()) {
+ if kind != FullCodeCharKind::Normal {
+ result.push(c);
+ } else if c == '$' {
+ dollar_count += 1;
+ } else if dollar_count == 0 {
+ result.push(c);
+ } else if !c.is_alphanumeric() && !cur_name.is_empty() {
+ // Terminates a name following one or more dollars.
+ register_metavariable(&mut substs, &mut result, &cur_name, dollar_count);
+
+ result.push(c);
+ dollar_count = 0;
+ cur_name.clear();
+ } else if c == '(' && cur_name.is_empty() {
+ // FIXME: Support macro def with repeat.
+ return None;
+ } else if c.is_alphanumeric() || c == '_' {
+ cur_name.push(c);
+ }
+ }
+
+ if !cur_name.is_empty() {
+ register_metavariable(&mut substs, &mut result, &cur_name, dollar_count);
+ }
+
+ debug!("replace_names `{}` {:?}", result, substs);
+
+ Some((result, substs))
+}
+
+#[derive(Debug, Clone)]
+enum MacroArgKind {
+ /// e.g., `$x: expr`.
+ MetaVariable(Symbol, String),
+ /// e.g., `$($foo: expr),*`
+ Repeat(
+ /// `()`, `[]` or `{}`.
+ DelimToken,
+ /// Inner arguments inside delimiters.
+ Vec<ParsedMacroArg>,
+ /// Something after the closing delimiter and the repeat token, if available.
+ Option<Box<ParsedMacroArg>>,
+ /// The repeat token. This could be one of `*`, `+` or `?`.
+ Token,
+ ),
+ /// e.g., `[derive(Debug)]`
+ Delimited(DelimToken, Vec<ParsedMacroArg>),
+ /// A possible separator. e.g., `,` or `;`.
+ Separator(String, String),
+ /// Other random stuff that does not fit to other kinds.
+ /// e.g., `== foo` in `($x: expr == foo)`.
+ Other(String, String),
+}
+
+fn delim_token_to_str(
+ context: &RewriteContext<'_>,
+ delim_token: DelimToken,
+ shape: Shape,
+ use_multiple_lines: bool,
+ inner_is_empty: bool,
+) -> (String, String) {
+ let (lhs, rhs) = match delim_token {
+ DelimToken::Paren => ("(", ")"),
+ DelimToken::Bracket => ("[", "]"),
+ DelimToken::Brace => {
+ if inner_is_empty || use_multiple_lines {
+ ("{", "}")
+ } else {
+ ("{ ", " }")
+ }
+ }
+ DelimToken::NoDelim => ("", ""),
+ };
+ if use_multiple_lines {
+ let indent_str = shape.indent.to_string_with_newline(context.config);
+ let nested_indent_str = shape
+ .indent
+ .block_indent(context.config)
+ .to_string_with_newline(context.config);
+ (
+ format!("{}{}", lhs, nested_indent_str),
+ format!("{}{}", indent_str, rhs),
+ )
+ } else {
+ (lhs.to_owned(), rhs.to_owned())
+ }
+}
+
+impl MacroArgKind {
+ fn starts_with_brace(&self) -> bool {
+ match *self {
+ MacroArgKind::Repeat(DelimToken::Brace, _, _, _)
+ | MacroArgKind::Delimited(DelimToken::Brace, _) => true,
+ _ => false,
+ }
+ }
+
+ fn starts_with_dollar(&self) -> bool {
+ match *self {
+ MacroArgKind::Repeat(..) | MacroArgKind::MetaVariable(..) => true,
+ _ => false,
+ }
+ }
+
+ fn ends_with_space(&self) -> bool {
+ match *self {
+ MacroArgKind::Separator(..) => true,
+ _ => false,
+ }
+ }
+
+ fn has_meta_var(&self) -> bool {
+ match *self {
+ MacroArgKind::MetaVariable(..) => true,
+ MacroArgKind::Repeat(_, ref args, _, _) => args.iter().any(|a| a.kind.has_meta_var()),
+ _ => false,
+ }
+ }
+
+ fn rewrite(
+ &self,
+ context: &RewriteContext<'_>,
+ shape: Shape,
+ use_multiple_lines: bool,
+ ) -> Option<String> {
+ let rewrite_delimited_inner = |delim_tok, args| -> Option<(String, String, String)> {
+ let inner = wrap_macro_args(context, args, shape)?;
+ let (lhs, rhs) = delim_token_to_str(context, delim_tok, shape, false, inner.is_empty());
+ if lhs.len() + inner.len() + rhs.len() <= shape.width {
+ return Some((lhs, inner, rhs));
+ }
+
+ let (lhs, rhs) = delim_token_to_str(context, delim_tok, shape, true, false);
+ let nested_shape = shape
+ .block_indent(context.config.tab_spaces())
+ .with_max_width(context.config);
+ let inner = wrap_macro_args(context, args, nested_shape)?;
+ Some((lhs, inner, rhs))
+ };
+
+ match *self {
+ MacroArgKind::MetaVariable(ty, ref name) => Some(format!("${}:{}", name, ty)),
+ MacroArgKind::Repeat(delim_tok, ref args, ref another, ref tok) => {
+ let (lhs, inner, rhs) = rewrite_delimited_inner(delim_tok, args)?;
+ let another = another
+ .as_ref()
+ .and_then(|a| a.rewrite(context, shape, use_multiple_lines))
+ .unwrap_or_else(|| "".to_owned());
+ let repeat_tok = pprust::token_to_string(tok);
+
+ Some(format!("${}{}{}{}{}", lhs, inner, rhs, another, repeat_tok))
+ }
+ MacroArgKind::Delimited(delim_tok, ref args) => {
+ rewrite_delimited_inner(delim_tok, args)
+ .map(|(lhs, inner, rhs)| format!("{}{}{}", lhs, inner, rhs))
+ }
+ MacroArgKind::Separator(ref sep, ref prefix) => Some(format!("{}{} ", prefix, sep)),
+ MacroArgKind::Other(ref inner, ref prefix) => Some(format!("{}{}", prefix, inner)),
+ }
+ }
+}
+
+#[derive(Debug, Clone)]
+struct ParsedMacroArg {
+ kind: MacroArgKind,
+ span: Span,
+}
+
+impl ParsedMacroArg {
+ fn rewrite(
+ &self,
+ context: &RewriteContext<'_>,
+ shape: Shape,
+ use_multiple_lines: bool,
+ ) -> Option<String> {
+ self.kind.rewrite(context, shape, use_multiple_lines)
+ }
+}
+
+/// Parses macro arguments on macro def.
+struct MacroArgParser {
+ /// Either a name of the next metavariable, a separator, or junk.
+ buf: String,
+ /// The start position on the current buffer.
+ lo: BytePos,
+ /// The first token of the current buffer.
+ start_tok: Token,
+ /// `true` if we are parsing a metavariable or a repeat.
+ is_meta_var: bool,
+ /// The position of the last token.
+ hi: BytePos,
+ /// The last token parsed.
+ last_tok: Token,
+ /// Holds the parsed arguments.
+ result: Vec<ParsedMacroArg>,
+}
+
+fn last_tok(tt: &TokenTree) -> Token {
+ match *tt {
+ TokenTree::Token(ref t) => t.clone(),
+ TokenTree::Delimited(delim_span, delim, _) => Token {
+ kind: TokenKind::CloseDelim(delim),
+ span: delim_span.close,
+ },
+ }
+}
+
+impl MacroArgParser {
+ fn new() -> MacroArgParser {
+ MacroArgParser {
+ lo: BytePos(0),
+ hi: BytePos(0),
+ buf: String::new(),
+ is_meta_var: false,
+ last_tok: Token {
+ kind: TokenKind::Eof,
+ span: DUMMY_SP,
+ },
+ start_tok: Token {
+ kind: TokenKind::Eof,
+ span: DUMMY_SP,
+ },
+ result: vec![],
+ }
+ }
+
+ fn set_last_tok(&mut self, tok: &TokenTree) {
+ self.hi = tok.span().hi();
+ self.last_tok = last_tok(tok);
+ }
+
+ fn add_separator(&mut self) {
+ let prefix = if self.need_space_prefix() {
+ " ".to_owned()
+ } else {
+ "".to_owned()
+ };
+ self.result.push(ParsedMacroArg {
+ kind: MacroArgKind::Separator(self.buf.clone(), prefix),
+ span: mk_sp(self.lo, self.hi),
+ });
+ self.buf.clear();
+ }
+
+ fn add_other(&mut self) {
+ let prefix = if self.need_space_prefix() {
+ " ".to_owned()
+ } else {
+ "".to_owned()
+ };
+ self.result.push(ParsedMacroArg {
+ kind: MacroArgKind::Other(self.buf.clone(), prefix),
+ span: mk_sp(self.lo, self.hi),
+ });
+ self.buf.clear();
+ }
+
+ fn add_meta_variable(&mut self, iter: &mut Cursor) -> Option<()> {
+ match iter.next() {
+ Some(TokenTree::Token(Token {
+ kind: TokenKind::Ident(name, _),
+ span,
+ })) => {
+ self.result.push(ParsedMacroArg {
+ kind: MacroArgKind::MetaVariable(name, self.buf.clone()),
+ span: mk_sp(self.lo, span.hi()),
+ });
+
+ self.buf.clear();
+ self.is_meta_var = false;
+ Some(())
+ }
+ _ => None,
+ }
+ }
+
+ fn add_delimited(&mut self, inner: Vec<ParsedMacroArg>, delim: DelimToken, span: Span) {
+ self.result.push(ParsedMacroArg {
+ kind: MacroArgKind::Delimited(delim, inner),
+ span,
+ });
+ }
+
+ // $($foo: expr),?
+ fn add_repeat(
+ &mut self,
+ inner: Vec<ParsedMacroArg>,
+ delim: DelimToken,
+ iter: &mut Cursor,
+ span: Span,
+ ) -> Option<()> {
+ let mut buffer = String::new();
+ let mut first = true;
+ let mut lo = span.lo();
+ let mut hi = span.hi();
+
+ // Parse '*', '+' or '?.
+ for tok in iter {
+ self.set_last_tok(&tok);
+ if first {
+ first = false;
+ lo = tok.span().lo();
+ }
+
+ match tok {
+ TokenTree::Token(Token {
+ kind: TokenKind::BinOp(BinOpToken::Plus),
+ ..
+ })
+ | TokenTree::Token(Token {
+ kind: TokenKind::Question,
+ ..
+ })
+ | TokenTree::Token(Token {
+ kind: TokenKind::BinOp(BinOpToken::Star),
+ ..
+ }) => {
+ break;
+ }
+ TokenTree::Token(ref t) => {
+ buffer.push_str(&pprust::token_to_string(&t));
+ hi = t.span.hi();
+ }
+ _ => return None,
+ }
+ }
+
+ // There could be some random stuff between ')' and '*', '+' or '?'.
+ let another = if buffer.trim().is_empty() {
+ None
+ } else {
+ Some(Box::new(ParsedMacroArg {
+ kind: MacroArgKind::Other(buffer, "".to_owned()),
+ span: mk_sp(lo, hi),
+ }))
+ };
+
+ self.result.push(ParsedMacroArg {
+ kind: MacroArgKind::Repeat(delim, inner, another, self.last_tok.clone()),
+ span: mk_sp(self.lo, self.hi),
+ });
+ Some(())
+ }
+
+ fn update_buffer(&mut self, t: &Token) {
+ if self.buf.is_empty() {
+ self.lo = t.span.lo();
+ self.start_tok = t.clone();
+ } else {
+ let needs_space = match next_space(&self.last_tok.kind) {
+ SpaceState::Ident => ident_like(t),
+ SpaceState::Punctuation => !ident_like(t),
+ SpaceState::Always => true,
+ SpaceState::Never => false,
+ };
+ if force_space_before(&t.kind) || needs_space {
+ self.buf.push(' ');
+ }
+ }
+
+ self.buf.push_str(&pprust::token_to_string(t));
+ }
+
+ fn need_space_prefix(&self) -> bool {
+ if self.result.is_empty() {
+ return false;
+ }
+
+ let last_arg = self.result.last().unwrap();
+ if let MacroArgKind::MetaVariable(..) = last_arg.kind {
+ if ident_like(&self.start_tok) {
+ return true;
+ }
+ if self.start_tok.kind == TokenKind::Colon {
+ return true;
+ }
+ }
+
+ if force_space_before(&self.start_tok.kind) {
+ return true;
+ }
+
+ false
+ }
+
+ /// Returns a collection of parsed macro def's arguments.
+ fn parse(mut self, tokens: TokenStream) -> Option<Vec<ParsedMacroArg>> {
+ let mut iter = tokens.trees();
+
+ while let Some(tok) = iter.next() {
+ match tok {
+ TokenTree::Token(Token {
+ kind: TokenKind::Dollar,
+ span,
+ }) => {
+ // We always want to add a separator before meta variables.
+ if !self.buf.is_empty() {
+ self.add_separator();
+ }
+
+ // Start keeping the name of this metavariable in the buffer.
+ self.is_meta_var = true;
+ self.lo = span.lo();
+ self.start_tok = Token {
+ kind: TokenKind::Dollar,
+ span,
+ };
+ }
+ TokenTree::Token(Token {
+ kind: TokenKind::Colon,
+ ..
+ }) if self.is_meta_var => {
+ self.add_meta_variable(&mut iter)?;
+ }
+ TokenTree::Token(ref t) => self.update_buffer(t),
+ TokenTree::Delimited(delimited_span, delimited, ref tts) => {
+ if !self.buf.is_empty() {
+ if next_space(&self.last_tok.kind) == SpaceState::Always {
+ self.add_separator();
+ } else {
+ self.add_other();
+ }
+ }
+
+ // Parse the stuff inside delimiters.
+ let mut parser = MacroArgParser::new();
+ parser.lo = delimited_span.open.lo();
+ let delimited_arg = parser.parse(tts.clone())?;
+
+ let span = delimited_span.entire();
+ if self.is_meta_var {
+ self.add_repeat(delimited_arg, delimited, &mut iter, span)?;
+ self.is_meta_var = false;
+ } else {
+ self.add_delimited(delimited_arg, delimited, span);
+ }
+ }
+ }
+
+ self.set_last_tok(&tok);
+ }
+
+ // We are left with some stuff in the buffer. Since there is nothing
+ // left to separate, add this as `Other`.
+ if !self.buf.is_empty() {
+ self.add_other();
+ }
+
+ Some(self.result)
+ }
+}
+
+fn wrap_macro_args(
+ context: &RewriteContext<'_>,
+ args: &[ParsedMacroArg],
+ shape: Shape,
+) -> Option<String> {
+ wrap_macro_args_inner(context, args, shape, false)
+ .or_else(|| wrap_macro_args_inner(context, args, shape, true))
+}
+
+fn wrap_macro_args_inner(
+ context: &RewriteContext<'_>,
+ args: &[ParsedMacroArg],
+ shape: Shape,
+ use_multiple_lines: bool,
+) -> Option<String> {
+ let mut result = String::with_capacity(128);
+ let mut iter = args.iter().peekable();
+ let indent_str = shape.indent.to_string_with_newline(context.config);
+
+ while let Some(ref arg) = iter.next() {
+ result.push_str(&arg.rewrite(context, shape, use_multiple_lines)?);
+
+ if use_multiple_lines
+ && (arg.kind.ends_with_space() || iter.peek().map_or(false, |a| a.kind.has_meta_var()))
+ {
+ if arg.kind.ends_with_space() {
+ result.pop();
+ }
+ result.push_str(&indent_str);
+ } else if let Some(ref next_arg) = iter.peek() {
+ let space_before_dollar =
+ !arg.kind.ends_with_space() && next_arg.kind.starts_with_dollar();
+ let space_before_brace = next_arg.kind.starts_with_brace();
+ if space_before_dollar || space_before_brace {
+ result.push(' ');
+ }
+ }
+ }
+
+ if !use_multiple_lines && result.len() >= shape.width {
+ None
+ } else {
+ Some(result)
+ }
+}
+
+// This is a bit sketchy. The token rules probably need tweaking, but it works
+// for some common cases. I hope the basic logic is sufficient. Note that the
+// meaning of some tokens is a bit different here from usual Rust, e.g., `*`
+// and `(`/`)` have special meaning.
+//
+// We always try and format on one line.
+// FIXME: Use multi-line when every thing does not fit on one line.
+fn format_macro_args(
+ context: &RewriteContext<'_>,
+ token_stream: TokenStream,
+ shape: Shape,
+) -> Option<String> {
+ if !context.config.format_macro_matchers() {
+ let span = span_for_token_stream(&token_stream);
+ return Some(match span {
+ Some(span) => context.snippet(span).to_owned(),
+ None => String::new(),
+ });
+ }
+ let parsed_args = MacroArgParser::new().parse(token_stream)?;
+ wrap_macro_args(context, &parsed_args, shape)
+}
+
+fn span_for_token_stream(token_stream: &TokenStream) -> Option<Span> {
+ token_stream.trees().next().map(|tt| tt.span())
+}
+
+// We should insert a space if the next token is a:
+#[derive(Copy, Clone, PartialEq)]
+enum SpaceState {
+ Never,
+ Punctuation,
+ Ident, // Or ident/literal-like thing.
+ Always,
+}
+
+fn force_space_before(tok: &TokenKind) -> bool {
+ debug!("tok: force_space_before {:?}", tok);
+
+ match tok {
+ TokenKind::Eq
+ | TokenKind::Lt
+ | TokenKind::Le
+ | TokenKind::EqEq
+ | TokenKind::Ne
+ | TokenKind::Ge
+ | TokenKind::Gt
+ | TokenKind::AndAnd
+ | TokenKind::OrOr
+ | TokenKind::Not
+ | TokenKind::Tilde
+ | TokenKind::BinOpEq(_)
+ | TokenKind::At
+ | TokenKind::RArrow
+ | TokenKind::LArrow
+ | TokenKind::FatArrow
+ | TokenKind::BinOp(_)
+ | TokenKind::Pound
+ | TokenKind::Dollar => true,
+ _ => false,
+ }
+}
+
+fn ident_like(tok: &Token) -> bool {
+ match tok.kind {
+ TokenKind::Ident(..) | TokenKind::Literal(..) | TokenKind::Lifetime(_) => true,
+ _ => false,
+ }
+}
+
+fn next_space(tok: &TokenKind) -> SpaceState {
+ debug!("next_space: {:?}", tok);
+
+ match tok {
+ TokenKind::Not
+ | TokenKind::BinOp(BinOpToken::And)
+ | TokenKind::Tilde
+ | TokenKind::At
+ | TokenKind::Comma
+ | TokenKind::Dot
+ | TokenKind::DotDot
+ | TokenKind::DotDotDot
+ | TokenKind::DotDotEq
+ | TokenKind::Question => SpaceState::Punctuation,
+
+ TokenKind::ModSep
+ | TokenKind::Pound
+ | TokenKind::Dollar
+ | TokenKind::OpenDelim(_)
+ | TokenKind::CloseDelim(_) => SpaceState::Never,
+
+ TokenKind::Literal(..) | TokenKind::Ident(..) | TokenKind::Lifetime(_) => SpaceState::Ident,
+
+ _ => SpaceState::Always,
+ }
+}
+
+/// Tries to convert a macro use into a short hand try expression. Returns `None`
+/// when the macro is not an instance of `try!` (or parsing the inner expression
+/// failed).
+pub(crate) fn convert_try_mac(
+ mac: &ast::MacCall,
+ context: &RewriteContext<'_>,
+) -> Option<ast::Expr> {
+ let path = &pprust::path_to_string(&mac.path);
+ if path == "try" || path == "r#try" {
+ let ts = mac.args.inner_tokens();
+ let mut parser = build_parser(context, ts.trees());
+
+ Some(ast::Expr {
+ id: ast::NodeId::root(), // dummy value
+ kind: ast::ExprKind::Try(parser.parse_expr().ok()?),
+ span: mac.span(), // incorrect span, but shouldn't matter too much
+ attrs: ast::AttrVec::new(),
+ tokens: Some(LazyTokenStream::new(ts)),
+ })
+ } else {
+ None
+ }
+}
+
+pub(crate) fn macro_style(mac: &ast::MacCall, context: &RewriteContext<'_>) -> DelimToken {
+ let snippet = context.snippet(mac.span());
+ let paren_pos = snippet.find_uncommented("(").unwrap_or(usize::max_value());
+ let bracket_pos = snippet.find_uncommented("[").unwrap_or(usize::max_value());
+ let brace_pos = snippet.find_uncommented("{").unwrap_or(usize::max_value());
+
+ if paren_pos < bracket_pos && paren_pos < brace_pos {
+ DelimToken::Paren
+ } else if bracket_pos < brace_pos {
+ DelimToken::Bracket
+ } else {
+ DelimToken::Brace
+ }
+}
+
+// A very simple parser that just parses a macros 2.0 definition into its branches.
+// Currently we do not attempt to parse any further than that.
+#[derive(new)]
+struct MacroParser {
+ toks: Cursor,
+}
+
+impl MacroParser {
+ // (`(` ... `)` `=>` `{` ... `}`)*
+ fn parse(&mut self) -> Option<Macro> {
+ let mut branches = vec![];
+ while self.toks.look_ahead(1).is_some() {
+ branches.push(self.parse_branch()?);
+ }
+
+ Some(Macro { branches })
+ }
+
+ // `(` ... `)` `=>` `{` ... `}`
+ fn parse_branch(&mut self) -> Option<MacroBranch> {
+ let tok = self.toks.next()?;
+ let (lo, args_paren_kind) = match tok {
+ TokenTree::Token(..) => return None,
+ TokenTree::Delimited(delimited_span, d, _) => (delimited_span.open.lo(), d),
+ };
+ let args = tok.joint();
+ match self.toks.next()? {
+ TokenTree::Token(Token {
+ kind: TokenKind::FatArrow,
+ ..
+ }) => {}
+ _ => return None,
+ }
+ let (mut hi, body, whole_body) = match self.toks.next()? {
+ TokenTree::Token(..) => return None,
+ TokenTree::Delimited(delimited_span, ..) => {
+ let data = delimited_span.entire().data();
+ (
+ data.hi,
+ Span::new(data.lo + BytePos(1), data.hi - BytePos(1), data.ctxt),
+ delimited_span.entire(),
+ )
+ }
+ };
+ if let Some(TokenTree::Token(Token {
+ kind: TokenKind::Semi,
+ span,
+ })) = self.toks.look_ahead(0)
+ {
+ hi = span.hi();
+ self.toks.next();
+ }
+ Some(MacroBranch {
+ span: mk_sp(lo, hi),
+ args_paren_kind,
+ args,
+ body,
+ whole_body,
+ })
+ }
+}
+
+// A parsed macros 2.0 macro definition.
+struct Macro {
+ branches: Vec<MacroBranch>,
+}
+
+// FIXME: it would be more efficient to use references to the token streams
+// rather than clone them, if we can make the borrowing work out.
+struct MacroBranch {
+ span: Span,
+ args_paren_kind: DelimToken,
+ args: TokenStream,
+ body: Span,
+ whole_body: Span,
+}
+
+impl MacroBranch {
+ fn rewrite(
+ &self,
+ context: &RewriteContext<'_>,
+ shape: Shape,
+ multi_branch_style: bool,
+ ) -> Option<String> {
+ // Only attempt to format function-like macros.
+ if self.args_paren_kind != DelimToken::Paren {
+ // FIXME(#1539): implement for non-sugared macros.
+ return None;
+ }
+
+ // 5 = " => {"
+ let mut result = format_macro_args(context, self.args.clone(), shape.sub_width(5)?)?;
+
+ if multi_branch_style {
+ result += " =>";
+ }
+
+ if !context.config.format_macro_bodies() {
+ result += " ";
+ result += context.snippet(self.whole_body);
+ return Some(result);
+ }
+
+ // The macro body is the most interesting part. It might end up as various
+ // AST nodes, but also has special variables (e.g, `$foo`) which can't be
+ // parsed as regular Rust code (and note that these can be escaped using
+ // `$$`). We'll try and format like an AST node, but we'll substitute
+ // variables for new names with the same length first.
+
+ let old_body = context.snippet(self.body).trim();
+ let (body_str, substs) = replace_names(old_body)?;
+ let has_block_body = old_body.starts_with('{');
+
+ let mut config = context.config.clone();
+ config.set().hide_parse_errors(true);
+
+ result += " {";
+
+ let body_indent = if has_block_body {
+ shape.indent
+ } else {
+ shape.indent.block_indent(&config)
+ };
+ let new_width = config.max_width() - body_indent.width();
+ config.set().max_width(new_width);
+
+ // First try to format as items, then as statements.
+ let new_body_snippet = match crate::format_snippet(&body_str, &config, true) {
+ Some(new_body) => new_body,
+ None => {
+ let new_width = new_width + config.tab_spaces();
+ config.set().max_width(new_width);
+ match crate::format_code_block(&body_str, &config, true) {
+ Some(new_body) => new_body,
+ None => return None,
+ }
+ }
+ };
+ let new_body = wrap_str(
+ new_body_snippet.snippet.to_string(),
+ config.max_width(),
+ shape,
+ )?;
+
+ // Indent the body since it is in a block.
+ let indent_str = body_indent.to_string(&config);
+ let mut new_body = LineClasses::new(new_body.trim_end())
+ .enumerate()
+ .fold(
+ (String::new(), true),
+ |(mut s, need_indent), (i, (kind, ref l))| {
+ if !is_empty_line(l)
+ && need_indent
+ && !new_body_snippet.is_line_non_formatted(i + 1)
+ {
+ s += &indent_str;
+ }
+ (s + l + "\n", indent_next_line(kind, &l, &config))
+ },
+ )
+ .0;
+
+ // Undo our replacement of macro variables.
+ // FIXME: this could be *much* more efficient.
+ for (old, new) in &substs {
+ if old_body.find(new).is_some() {
+ debug!("rewrite_macro_def: bailing matching variable: `{}`", new);
+ return None;
+ }
+ new_body = new_body.replace(new, old);
+ }
+
+ if has_block_body {
+ result += new_body.trim();
+ } else if !new_body.is_empty() {
+ result += "\n";
+ result += &new_body;
+ result += &shape.indent.to_string(&config);
+ }
+
+ result += "}";
+
+ Some(result)
+ }
+}
+
+/// Format `lazy_static!` from https://crates.io/crates/lazy_static.
+///
+/// # Expected syntax
+///
+/// ```text
+/// lazy_static! {
+/// [pub] static ref NAME_1: TYPE_1 = EXPR_1;
+/// [pub] static ref NAME_2: TYPE_2 = EXPR_2;
+/// ...
+/// [pub] static ref NAME_N: TYPE_N = EXPR_N;
+/// }
+/// ```
+fn format_lazy_static(
+ context: &RewriteContext<'_>,
+ shape: Shape,
+ ts: &TokenStream,
+) -> Option<String> {
+ let mut result = String::with_capacity(1024);
+ let mut parser = build_parser(context, ts.trees());
+ let nested_shape = shape
+ .block_indent(context.config.tab_spaces())
+ .with_max_width(context.config);
+
+ result.push_str("lazy_static! {");
+ result.push_str(&nested_shape.indent.to_string_with_newline(context.config));
+
+ macro_rules! parse_or {
+ ($method:ident $(,)* $($arg:expr),* $(,)*) => {
+ match parser.$method($($arg,)*) {
+ Ok(val) => {
+ if parser.sess.span_diagnostic.has_errors() {
+ parser.sess.span_diagnostic.reset_err_count();
+ return None;
+ } else {
+ val
+ }
+ }
+ Err(mut err) => {
+ err.cancel();
+ parser.sess.span_diagnostic.reset_err_count();
+ return None;
+ }
+ }
+ }
+ }
+
+ while parser.token.kind != TokenKind::Eof {
+ // Parse a `lazy_static!` item.
+ let vis = crate::utils::format_visibility(
+ context,
+ &parse_or!(parse_visibility, rustc_parse::parser::FollowedByType::No),
+ );
+ parser.eat_keyword(kw::Static);
+ parser.eat_keyword(kw::Ref);
+ let id = parse_or!(parse_ident);
+ parser.eat(&TokenKind::Colon);
+ let ty = parse_or!(parse_ty);
+ parser.eat(&TokenKind::Eq);
+ let expr = parse_or!(parse_expr);
+ parser.eat(&TokenKind::Semi);
+
+ // Rewrite as a static item.
+ let mut stmt = String::with_capacity(128);
+ stmt.push_str(&format!(
+ "{}static ref {}: {} =",
+ vis,
+ id,
+ ty.rewrite(context, nested_shape)?
+ ));
+ result.push_str(&crate::expr::rewrite_assign_rhs(
+ context,
+ stmt,
+ &*expr,
+ nested_shape.sub_width(1)?,
+ )?);
+ result.push(';');
+ if parser.token.kind != TokenKind::Eof {
+ result.push_str(&nested_shape.indent.to_string_with_newline(context.config));
+ }
+ }
+
+ result.push_str(&shape.indent.to_string_with_newline(context.config));
+ result.push('}');
+
+ Some(result)
+}
+
+fn rewrite_macro_with_items(
+ context: &RewriteContext<'_>,
+ items: &[MacroArg],
+ macro_name: &str,
+ shape: Shape,
+ style: DelimToken,
+ position: MacroPosition,
+ span: Span,
+) -> Option<String> {
+ let (opener, closer) = match style {
+ DelimToken::Paren => ("(", ")"),
+ DelimToken::Bracket => ("[", "]"),
+ DelimToken::Brace => (" {", "}"),
+ _ => return None,
+ };
+ let trailing_semicolon = match style {
+ DelimToken::Paren | DelimToken::Bracket if position == MacroPosition::Item => ";",
+ _ => "",
+ };
+
+ let mut visitor = FmtVisitor::from_context(context);
+ visitor.block_indent = shape.indent.block_indent(context.config);
+ visitor.last_pos = context.snippet_provider.span_after(span, opener.trim());
+ for item in items {
+ let item = match item {
+ MacroArg::Item(item) => item,
+ _ => return None,
+ };
+ visitor.visit_item(&item);
+ }
+
+ let mut result = String::with_capacity(256);
+ result.push_str(¯o_name);
+ result.push_str(opener);
+ result.push_str(&visitor.block_indent.to_string_with_newline(context.config));
+ result.push_str(visitor.buffer.trim());
+ result.push_str(&shape.indent.to_string_with_newline(context.config));
+ result.push_str(closer);
+ result.push_str(trailing_semicolon);
+ Some(result)
+}
+
+const RUST_KW: [Symbol; 59] = [
+ kw::PathRoot,
+ kw::DollarCrate,
+ kw::Underscore,
+ kw::As,
+ kw::Box,
+ kw::Break,
+ kw::Const,
+ kw::Continue,
+ kw::Crate,
+ kw::Else,
+ kw::Enum,
+ kw::Extern,
+ kw::False,
+ kw::Fn,
+ kw::For,
+ kw::If,
+ kw::Impl,
+ kw::In,
+ kw::Let,
+ kw::Loop,
+ kw::Match,
+ kw::Mod,
+ kw::Move,
+ kw::Mut,
+ kw::Pub,
+ kw::Ref,
+ kw::Return,
+ kw::SelfLower,
+ kw::SelfUpper,
+ kw::Static,
+ kw::Struct,
+ kw::Super,
+ kw::Trait,
+ kw::True,
+ kw::Type,
+ kw::Unsafe,
+ kw::Use,
+ kw::Where,
+ kw::While,
+ kw::Abstract,
+ kw::Become,
+ kw::Do,
+ kw::Final,
+ kw::Macro,
+ kw::Override,
+ kw::Priv,
+ kw::Typeof,
+ kw::Unsized,
+ kw::Virtual,
+ kw::Yield,
+ kw::Dyn,
+ kw::Async,
+ kw::Try,
+ kw::UnderscoreLifetime,
+ kw::StaticLifetime,
+ kw::Auto,
+ kw::Catch,
+ kw::Default,
+ kw::Union,
+];
projects / rustc.git / blobdiff