rust-lang/rust
1
0
Fork 0
Code Issues Pull Requests Actions 1 Packages Projects Releases Wiki Activity

Do not parenthesize exterior struct lit inside match guards

Browse Source
This commit is contained in:
David Tolnay
2023-11-29 21:32:32 -08:00
parent 7f314acc34
commit 6f1d7631fb
4 changed files with 150 additions and 75 deletions
Download Patch File Download Diff File Expand all files Collapse all files

68
compiler/rustc_ast_pretty/src/pprust/state.rs
View File

@@ -7,6 +7,7 @@ mod item;
use crate::pp::Breaks::{Consistent, Inconsistent};
use crate::pp::{self, Breaks};
use crate::pprust::state::expr::FixupContext;
use rustc_ast::attr::AttrIdGenerator;
use rustc_ast::ptr::P;
use rustc_ast::token::{self, BinOpToken, CommentKind, Delimiter, Nonterminal, Token, TokenKind};
@@ -798,7 +799,7 @@ pub trait PrintState<'a>: std::ops::Deref<Target = pp::Printer> + std::ops::Dere
}
fn expr_to_string(&self, e: &ast::Expr) -> String {
Self::to_string(|s| s.print_expr(e))
Self::to_string(|s| s.print_expr(e, FixupContext::default()))
}
fn meta_item_lit_to_string(&self, lit: &ast::MetaItemLit) -> String {
@@ -903,7 +904,7 @@ impl<'a> State<'a> {
}
fn commasep_exprs(&mut self, b: Breaks, exprs: &[P<ast::Expr>]) {
self.commasep_cmnt(b, exprs, |s, e| s.print_expr(e), |e| e.span)
self.commasep_cmnt(b, exprs, |s, e| s.print_expr(e, FixupContext::default()), |e| e.span)
}
pub fn print_opt_lifetime(&mut self, lifetime: &Option<ast::Lifetime>) {
@@ -940,7 +941,7 @@ impl<'a> State<'a> {
match generic_arg {
GenericArg::Lifetime(lt) => self.print_lifetime(*lt),
GenericArg::Type(ty) => self.print_type(ty),
GenericArg::Const(ct) => self.print_expr(&ct.value),
GenericArg::Const(ct) => self.print_expr(&ct.value, FixupContext::default()),
}
}
@@ -1007,12 +1008,12 @@ impl<'a> State<'a> {
self.word("[");
self.print_type(ty);
self.word("; ");
self.print_expr(&length.value);
self.print_expr(&length.value, FixupContext::default());
self.word("]");
}
ast::TyKind::Typeof(e) => {
self.word("typeof(");
self.print_expr(&e.value);
self.print_expr(&e.value, FixupContext::default());
self.word(")");
}
ast::TyKind::Infer => {
@@ -1068,7 +1069,7 @@ impl<'a> State<'a> {
if let Some((init, els)) = loc.kind.init_else_opt() {
self.nbsp();
self.word_space("=");
self.print_expr(init);
self.print_expr(init, FixupContext::default());
if let Some(els) = els {
self.cbox(INDENT_UNIT);
self.ibox(INDENT_UNIT);
@@ -1082,14 +1083,14 @@ impl<'a> State<'a> {
ast::StmtKind::Item(item) => self.print_item(item),
ast::StmtKind::Expr(expr) => {
self.space_if_not_bol();
self.print_expr_outer_attr_style(expr, false);
self.print_expr_outer_attr_style(expr, false, FixupContext::default());
if classify::expr_requires_semi_to_be_stmt(expr) {
self.word(";");
}
}
ast::StmtKind::Semi(expr) => {
self.space_if_not_bol();
self.print_expr_outer_attr_style(expr, false);
self.print_expr_outer_attr_style(expr, false, FixupContext::default());
self.word(";");
}
ast::StmtKind::Empty => {
@@ -1141,7 +1142,7 @@ impl<'a> State<'a> {
ast::StmtKind::Expr(expr) if i == blk.stmts.len() - 1 => {
self.maybe_print_comment(st.span.lo());
self.space_if_not_bol();
self.print_expr_outer_attr_style(expr, false);
self.print_expr_outer_attr_style(expr, false, FixupContext::default());
self.maybe_print_trailing_comment(expr.span, Some(blk.span.hi()));
}
_ => self.print_stmt(st),
@@ -1154,15 +1155,40 @@ impl<'a> State<'a> {
}
/// Print a `let pat = expr` expression.
fn print_let(&mut self, pat: &ast::Pat, expr: &ast::Expr) {
///
/// Parentheses are inserted surrounding `expr` if a round-trip through the
/// parser would otherwise work out the wrong way in a condition position.
///
/// For example each of the following would mean the wrong thing without
/// parentheses.
///
/// ```ignore
/// if let _ = (Struct {}) {}
///
/// if let _ = (true && false) {}
/// ```
///
/// In a match guard, the second case still requires parens, but the first
/// case no longer does because anything until `=>` is considered part of
/// the match guard expression. Parsing of the expression is not terminated
/// by `{` in that position.
///
/// ```ignore
/// match () {
/// () if let _ = Struct {} => {}
/// () if let _ = (true && false) => {}
/// }
/// ```
fn print_let(&mut self, pat: &ast::Pat, expr: &ast::Expr, fixup: FixupContext) {
self.word("let ");
self.print_pat(pat);
self.space();
self.word_space("=");
self.print_expr_cond_paren(
expr,
parser::contains_exterior_struct_lit(expr)
fixup.parenthesize_exterior_struct_lit && parser::contains_exterior_struct_lit(expr)
|| parser::needs_par_as_let_scrutinee(expr.precedence().order()),
FixupContext::default(),
);
}
@@ -1210,7 +1236,7 @@ impl<'a> State<'a> {
print_reg_or_class(s, reg);
s.pclose();
s.space();
s.print_expr(expr);
s.print_expr(expr, FixupContext::default());
}
InlineAsmOperand::Out { reg, late, expr } => {
s.word(if *late { "lateout" } else { "out" });
@@ -1219,7 +1245,7 @@ impl<'a> State<'a> {
s.pclose();
s.space();
match expr {
Some(expr) => s.print_expr(expr),
Some(expr) => s.print_expr(expr, FixupContext::default()),
None => s.word("_"),
}
}
@@ -1229,7 +1255,7 @@ impl<'a> State<'a> {
print_reg_or_class(s, reg);
s.pclose();
s.space();
s.print_expr(expr);
s.print_expr(expr, FixupContext::default());
}
InlineAsmOperand::SplitInOut { reg, late, in_expr, out_expr } => {
s.word(if *late { "inlateout" } else { "inout" });
@@ -1237,18 +1263,18 @@ impl<'a> State<'a> {
print_reg_or_class(s, reg);
s.pclose();
s.space();
s.print_expr(in_expr);
s.print_expr(in_expr, FixupContext::default());
s.space();
s.word_space("=>");
match out_expr {
Some(out_expr) => s.print_expr(out_expr),
Some(out_expr) => s.print_expr(out_expr, FixupContext::default()),
None => s.word("_"),
}
}
InlineAsmOperand::Const { anon_const } => {
s.word("const");
s.space();
s.print_expr(&anon_const.value);
s.print_expr(&anon_const.value, FixupContext::default());
}
InlineAsmOperand::Sym { sym } => {
s.word("sym");
@@ -1442,10 +1468,10 @@ impl<'a> State<'a> {
self.print_pat(inner);
}
}
PatKind::Lit(e) => self.print_expr(e),
PatKind::Lit(e) => self.print_expr(e, FixupContext::default()),
PatKind::Range(begin, end, Spanned { node: end_kind, .. }) => {
if let Some(e) = begin {
self.print_expr(e);
self.print_expr(e, FixupContext::default());
}
match end_kind {
RangeEnd::Included(RangeSyntax::DotDotDot) => self.word("..."),
@@ -1453,7 +1479,7 @@ impl<'a> State<'a> {
RangeEnd::Excluded => self.word(".."),
}
if let Some(e) = end {
self.print_expr(e);
self.print_expr(e, FixupContext::default());
}
}
PatKind::Slice(elts) => {
@@ -1607,7 +1633,7 @@ impl<'a> State<'a> {
if let Some(default) = default {
s.space();
s.word_space("=");
s.print_expr(&default.value);
s.print_expr(&default.value, FixupContext::default());
}
}
}