// 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
-// reformated.
+// reformatted.
// List-like invocations with parentheses will be formatted as function calls,
// and those with brackets will be formatted as array literals.
use syntax::ast;
use syntax::codemap::BytePos;
-use syntax::parse::token::Token;
use syntax::parse::new_parser_from_tts;
-use syntax::tokenstream::TokenStream;
+use syntax::parse::parser::Parser;
+use syntax::parse::token::Token;
use syntax::symbol;
+use syntax::tokenstream::TokenStream;
use syntax::util::ThinVec;
-use Shape;
use codemap::SpanUtils;
+use comment::{contains_comment, FindUncommented};
+use expr::{rewrite_array, rewrite_call_inner};
use rewrite::{Rewrite, RewriteContext};
-use expr::{rewrite_call, rewrite_array, rewrite_pair};
-use comment::{FindUncommented, contains_comment};
+use shape::{Indent, Shape};
use utils::mk_sp;
-const FORCED_BRACKET_MACROS: &'static [&'static str] = &["vec!"];
+const FORCED_BRACKET_MACROS: &[&str] = &["vec!"];
// FIXME: use the enum from libsyntax?
#[derive(Clone, Copy, PartialEq, Eq)]
Item,
Statement,
Expression,
+ Pat,
}
impl MacroStyle {
}
}
-pub fn rewrite_macro(mac: &ast::Mac,
- extra_ident: Option<ast::Ident>,
- context: &RewriteContext,
- shape: Shape,
- position: MacroPosition)
- -> Option<String> {
- let mut context = &mut context.clone();
+pub enum MacroArg {
+ Expr(ast::Expr),
+ Ty(ast::Ty),
+ Pat(ast::Pat),
+}
+
+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),
+ }
+ }
+}
+
+fn parse_macro_arg(parser: &mut Parser) -> Option<MacroArg> {
+ macro_rules! parse_macro_arg {
+ ($target:tt, $macro_arg:ident, $parser:ident) => {
+ let mut cloned_parser = (*parser).clone();
+ match cloned_parser.$parser() {
+ Ok($target) => {
+ if parser.sess.span_diagnostic.has_errors() {
+ parser.sess.span_diagnostic.reset_err_count();
+ } else {
+ // Parsing succeeded.
+ *parser = cloned_parser;
+ return Some(MacroArg::$macro_arg((*$target).clone()));
+ }
+ }
+ Err(mut e) => {
+ e.cancel();
+ parser.sess.span_diagnostic.reset_err_count();
+ }
+ }
+ }
+ }
+
+ parse_macro_arg!(expr, Expr, parse_expr);
+ parse_macro_arg!(ty, Ty, parse_ty);
+ parse_macro_arg!(pat, Pat, parse_pat);
+
+ None
+}
+
+pub fn rewrite_macro(
+ mac: &ast::Mac,
+ extra_ident: Option<ast::Ident>,
+ context: &RewriteContext,
+ shape: Shape,
+ position: MacroPosition,
+) -> Option<String> {
+ let context = &mut context.clone();
context.inside_macro = true;
if context.config.use_try_shorthand() {
if let Some(expr) = convert_try_mac(mac, context) {
+ context.inside_macro = false;
return expr.rewrite(context, shape);
}
}
original_style
};
- let ts: TokenStream = mac.node.tts.clone().into();
- if ts.is_empty() && !contains_comment(&context.snippet(mac.span)) {
+ let ts: TokenStream = mac.node.stream();
+ if ts.is_empty() && !contains_comment(context.snippet(mac.span)) {
return match style {
MacroStyle::Parens if position == MacroPosition::Item => {
Some(format!("{}();", macro_name))
}
let mut parser = new_parser_from_tts(context.parse_session, ts.trees().collect());
- let mut expr_vec = Vec::new();
+ let mut arg_vec = Vec::new();
let mut vec_with_semi = false;
+ let mut trailing_comma = false;
if MacroStyle::Braces != style {
loop {
- let expr = match parser.parse_expr() {
- Ok(expr) => {
- // Recovered errors.
- if context.parse_session.span_diagnostic.has_errors() {
- return Some(context.snippet(mac.span));
- }
-
- expr
- }
- Err(mut e) => {
- e.cancel();
- return Some(context.snippet(mac.span));
- }
- };
-
- expr_vec.push(expr);
+ match parse_macro_arg(&mut parser) {
+ Some(arg) => arg_vec.push(arg),
+ None => return Some(context.snippet(mac.span).to_owned()),
+ }
match parser.token {
Token::Eof => break,
if FORCED_BRACKET_MACROS.contains(&¯o_name[..]) {
parser.bump();
if parser.token != Token::Eof {
- match parser.parse_expr() {
- Ok(expr) => {
- if context.parse_session.span_diagnostic.has_errors() {
- return None;
- }
- expr_vec.push(expr);
+ match parse_macro_arg(&mut parser) {
+ Some(arg) => {
+ arg_vec.push(arg);
parser.bump();
- if parser.token == Token::Eof && expr_vec.len() == 2 {
+ if parser.token == Token::Eof && arg_vec.len() == 2 {
vec_with_semi = true;
break;
}
}
- Err(mut e) => e.cancel(),
+ None => return Some(context.snippet(mac.span).to_owned()),
}
}
}
- return None;
+ return Some(context.snippet(mac.span).to_owned());
}
- _ => return None,
+ _ => return Some(context.snippet(mac.span).to_owned()),
}
parser.bump();
if parser.token == Token::Eof {
- // vec! is a special case of bracket macro which should be formated as an array.
- if macro_name == "vec!" {
- break;
- } else {
- return None;
- }
+ trailing_comma = true;
+ break;
}
}
}
MacroStyle::Parens => {
// Format macro invocation as function call, forcing no trailing
// comma because not all macros support them.
- rewrite_call(context, ¯o_name, &expr_vec, mac.span, shape).map(
- |rw| match position {
- MacroPosition::Item => format!("{};", rw),
- _ => rw,
- },
- )
+ rewrite_call_inner(
+ context,
+ ¯o_name,
+ &arg_vec.iter().map(|e| &*e).collect::<Vec<_>>()[..],
+ mac.span,
+ shape,
+ context.config.width_heuristics().fn_call_width,
+ trailing_comma,
+ ).map(|rw| match position {
+ MacroPosition::Item => format!("{};", rw),
+ _ => rw,
+ })
}
MacroStyle::Brackets => {
- let mac_shape = try_opt!(shape.shrink_left(macro_name.len()));
+ let mac_shape = shape.offset_left(macro_name.len())?;
// Handle special case: `vec![expr; expr]`
if vec_with_semi {
- let (lbr, rbr) = if context.config.spaces_within_square_brackets() {
+ let (lbr, rbr) = if context.config.spaces_within_parens_and_brackets() {
("[ ", " ]")
} else {
("[", "]")
};
- rewrite_pair(&*expr_vec[0],
- &*expr_vec[1],
- lbr,
- "; ",
- rbr,
- context,
- mac_shape)
- .map(|s| format!("{}{}", macro_name, s))
+ // 6 = `vec!` + `; `
+ let total_overhead = lbr.len() + rbr.len() + 6;
+ 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
+ {
+ Some(format!("{}{}{}; {}{}", macro_name, lbr, lhs, rhs, rbr))
+ } else {
+ Some(format!(
+ "{}{}\n{}{};\n{}{}\n{}{}",
+ macro_name,
+ lbr,
+ nested_shape.indent.to_string(context.config),
+ lhs,
+ nested_shape.indent.to_string(context.config),
+ rhs,
+ shape.indent.to_string(context.config),
+ rbr
+ ))
+ }
} else {
- // Format macro invocation as array literal.
- let rewrite =
- try_opt!(rewrite_array(expr_vec.iter().map(|x| &**x),
- mk_sp(context
- .codemap
- .span_after(mac.span, original_style.opener()),
- mac.span.hi - BytePos(1)),
- context,
- mac_shape));
+ // 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.
+ if FORCED_BRACKET_MACROS.contains(¯o_name.as_str()) {
+ context.inside_macro = false;
+ trailing_comma = false;
+ }
+ // Convert `MacroArg` into `ast::Expr`, as `rewrite_array` only accepts the latter.
+ let sp = mk_sp(
+ context
+ .codemap
+ .span_after(mac.span, original_style.opener()),
+ mac.span.hi() - BytePos(1),
+ );
+ let arg_vec = &arg_vec.iter().map(|e| &*e).collect::<Vec<_>>()[..];
+ let rewrite = rewrite_array(arg_vec, sp, context, mac_shape, trailing_comma)?;
Some(format!("{}{}", macro_name, rewrite))
}
}
MacroStyle::Braces => {
// Skip macro invocations with braces, for now.
- None
+ indent_macro_snippet(context, context.snippet(mac.span), shape.indent)
}
}
}
let mut parser = new_parser_from_tts(context.parse_session, ts.trees().collect());
Some(ast::Expr {
- id: ast::NodeId::new(0), // dummy value
- node: ast::ExprKind::Try(try_opt!(parser.parse_expr().ok())),
- span: mac.span, // incorrect span, but shouldn't matter too much
- attrs: ThinVec::new(),
- })
+ id: ast::NodeId::new(0), // dummy value
+ node: ast::ExprKind::Try(parser.parse_expr().ok()?),
+ span: mac.span, // incorrect span, but shouldn't matter too much
+ attrs: ThinVec::new(),
+ })
} else {
None
}
MacroStyle::Braces
}
}
+
+/// Indent each line according to the specified `indent`.
+/// e.g.
+/// ```rust
+/// foo!{
+/// x,
+/// y,
+/// foo(
+/// a,
+/// b,
+/// c,
+/// ),
+/// }
+/// ```
+/// will become
+/// ```rust
+/// foo!{
+/// x,
+/// y,
+/// foo(
+/// a,
+/// b,
+/// c,
+// ),
+/// }
+/// ```
+fn indent_macro_snippet(
+ context: &RewriteContext,
+ macro_str: &str,
+ indent: Indent,
+) -> Option<String> {
+ let mut lines = macro_str.lines();
+ let first_line = lines.next().map(|s| s.trim_right())?;
+ let mut trimmed_lines = Vec::with_capacity(16);
+
+ let min_prefix_space_width = lines
+ .filter_map(|line| {
+ let prefix_space_width = if is_empty_line(line) {
+ None
+ } else {
+ Some(get_prefix_space_width(context, line))
+ };
+ trimmed_lines.push((line.trim(), prefix_space_width));
+ prefix_space_width
+ })
+ .min()?;
+
+ Some(
+ String::from(first_line) + "\n"
+ + &trimmed_lines
+ .iter()
+ .map(|&(line, prefix_space_width)| match prefix_space_width {
+ Some(original_indent_width) => {
+ let new_indent_width = indent.width()
+ + original_indent_width
+ .checked_sub(min_prefix_space_width)
+ .unwrap_or(0);
+ let new_indent = Indent::from_width(context.config, new_indent_width);
+ format!("{}{}", new_indent.to_string(context.config), line.trim())
+ }
+ None => String::new(),
+ })
+ .collect::<Vec<_>>()
+ .join("\n"),
+ )
+}
+
+fn get_prefix_space_width(context: &RewriteContext, s: &str) -> usize {
+ let mut width = 0;
+ for c in s.chars() {
+ match c {
+ ' ' => width += 1,
+ '\t' => width += context.config.tab_spaces(),
+ _ => return width,
+ }
+ }
+ width
+}
+
+fn is_empty_line(s: &str) -> bool {
+ s.is_empty() || s.chars().all(char::is_whitespace)
+}
projects / rust.git / blobdiff