use crate::pp::Breaks::Inconsistent;
use crate::pprust::state::{AnnNode, IterDelimited, PrintState, State, INDENT_UNIT};
use rustc_ast::ptr::P;
use rustc_ast::token;
use rustc_ast::util::literal::escape_byte_str_symbol;
use rustc_ast::util::parser::{self, AssocOp, Fixity};
use rustc_ast::{self as ast, BlockCheckMode};
use rustc_ast::{
FormatAlignment, FormatArgPosition, FormatArgsPiece, FormatCount, FormatDebugHex, FormatSign,
FormatTrait,
};
use std::fmt::Write;
impl<'a> State<'a> {
fn print_else(&mut self, els: Option<&ast::Expr>) {
if let Some(_else) = els {
match &_else.kind {
ast::ExprKind::If(i, then, e) => {
self.cbox(INDENT_UNIT - 1);
self.ibox(0);
self.word(" else if ");
self.print_expr_as_cond(i);
self.space();
self.print_block(then);
self.print_else(e.as_deref())
}
ast::ExprKind::Block(b, _) => {
self.cbox(INDENT_UNIT - 1);
self.ibox(0);
self.word(" else ");
self.print_block(b)
}
_ => {
panic!("print_if saw if with weird alternative");
}
}
}
}
fn print_if(&mut self, test: &ast::Expr, blk: &ast::Block, elseopt: Option<&ast::Expr>) {
self.head("if");
self.print_expr_as_cond(test);
self.space();
self.print_block(blk);
self.print_else(elseopt)
}
fn print_call_post(&mut self, args: &[P<ast::Expr>]) {
self.popen();
self.commasep_exprs(Inconsistent, args);
self.pclose()
}
fn print_expr_maybe_paren(&mut self, expr: &ast::Expr, prec: i8) {
self.print_expr_cond_paren(expr, expr.precedence().order() < prec)
}
fn print_expr_as_cond(&mut self, expr: &ast::Expr) {
self.print_expr_cond_paren(expr, Self::cond_needs_par(expr))
}
pub(super) fn cond_needs_par(expr: &ast::Expr) -> bool {
match expr.kind {
ast::ExprKind::Break(..)
| ast::ExprKind::Closure(..)
| ast::ExprKind::Ret(..)
| ast::ExprKind::Yeet(..) => true,
_ => parser::contains_exterior_struct_lit(expr),
}
}
pub(super) fn print_expr_cond_paren(&mut self, expr: &ast::Expr, needs_par: bool) {
if needs_par {
self.popen();
}
self.print_expr(expr);
if needs_par {
self.pclose();
}
}
fn print_expr_vec(&mut self, exprs: &[P<ast::Expr>]) {
self.ibox(INDENT_UNIT);
self.word("[");
self.commasep_exprs(Inconsistent, exprs);
self.word("]");
self.end();
}
pub(super) fn print_expr_anon_const(
&mut self,
expr: &ast::AnonConst,
attrs: &[ast::Attribute],
) {
self.ibox(INDENT_UNIT);
self.word("const");
self.nbsp();
if let ast::ExprKind::Block(block, None) = &expr.value.kind {
self.cbox(0);
self.ibox(0);
self.print_block_with_attrs(block, attrs);
} else {
self.print_expr(&expr.value);
}
self.end();
}
fn print_expr_repeat(&mut self, element: &ast::Expr, count: &ast::AnonConst) {
self.ibox(INDENT_UNIT);
self.word("[");
self.print_expr(element);
self.word_space(";");
self.print_expr(&count.value);
self.word("]");
self.end();
}
fn print_expr_struct(
&mut self,
qself: &Option<P<ast::QSelf>>,
path: &ast::Path,
fields: &[ast::ExprField],
rest: &ast::StructRest,
) {
if let Some(qself) = qself {
self.print_qpath(path, qself, true);
} else {
self.print_path(path, true, 0);
}
self.nbsp();
self.word("{");
let has_rest = match rest {
ast::StructRest::Base(_) | ast::StructRest::Rest(_) => true,
ast::StructRest::None => false,
};
if fields.is_empty() && !has_rest {
self.word("}");
return;
}
self.cbox(0);
for field in fields.iter().delimited() {
self.maybe_print_comment(field.span.hi());
self.print_outer_attributes(&field.attrs);
if field.is_first {
self.space_if_not_bol();
}
if !field.is_shorthand {
self.print_ident(field.ident);
self.word_nbsp(":");
}
self.print_expr(&field.expr);
if !field.is_last || has_rest {
self.word_space(",");
} else {
self.trailing_comma_or_space();
}
}
if has_rest {
if fields.is_empty() {
self.space();
}
self.word("..");
if let ast::StructRest::Base(expr) = rest {
self.print_expr(expr);
}
self.space();
}
self.offset(-INDENT_UNIT);
self.end();
self.word("}");
}
fn print_expr_tup(&mut self, exprs: &[P<ast::Expr>]) {
self.popen();
self.commasep_exprs(Inconsistent, exprs);
if exprs.len() == 1 {
self.word(",");
}
self.pclose()
}
fn print_expr_call(&mut self, func: &ast::Expr, args: &[P<ast::Expr>]) {
let prec = match func.kind {
ast::ExprKind::Field(..) => parser::PREC_FORCE_PAREN,
_ => parser::PREC_POSTFIX,
};
self.print_expr_maybe_paren(func, prec);
self.print_call_post(args)
}
fn print_expr_method_call(
&mut self,
segment: &ast::PathSegment,
receiver: &ast::Expr,
base_args: &[P<ast::Expr>],
) {
self.print_expr_maybe_paren(receiver, parser::PREC_POSTFIX);
self.word(".");
self.print_ident(segment.ident);
if let Some(args) = &segment.args {
self.print_generic_args(args, true);
}
self.print_call_post(base_args)
}
fn print_expr_binary(&mut self, op: ast::BinOp, lhs: &ast::Expr, rhs: &ast::Expr) {
let assoc_op = AssocOp::from_ast_binop(op.node);
let prec = assoc_op.precedence() as i8;
let fixity = assoc_op.fixity();
let (left_prec, right_prec) = match fixity {
Fixity::Left => (prec, prec + 1),
Fixity::Right => (prec + 1, prec),
Fixity::None => (prec + 1, prec + 1),
};
let left_prec = match (&lhs.kind, op.node) {
(&ast::ExprKind::Cast { .. }, ast::BinOpKind::Lt | ast::BinOpKind::Shl) => {
parser::PREC_FORCE_PAREN
}
(&ast::ExprKind::Let { .. }, _) if !parser::needs_par_as_let_scrutinee(prec) => {
parser::PREC_FORCE_PAREN
}
(&ast::ExprKind::Match(..), _) => parser::PREC_FORCE_PAREN,
_ => left_prec,
};
self.print_expr_maybe_paren(lhs, left_prec);
self.space();
self.word_space(op.node.to_string());
self.print_expr_maybe_paren(rhs, right_prec)
}
fn print_expr_unary(&mut self, op: ast::UnOp, expr: &ast::Expr) {
self.word(ast::UnOp::to_string(op));
self.print_expr_maybe_paren(expr, parser::PREC_PREFIX)
}
fn print_expr_addr_of(
&mut self,
kind: ast::BorrowKind,
mutability: ast::Mutability,
expr: &ast::Expr,
) {
self.word("&");
match kind {
ast::BorrowKind::Ref => self.print_mutability(mutability, false),
ast::BorrowKind::Raw => {
self.word_nbsp("raw");
self.print_mutability(mutability, true);
}
}
self.print_expr_maybe_paren(expr, parser::PREC_PREFIX)
}
pub fn print_expr(&mut self, expr: &ast::Expr) {
self.print_expr_outer_attr_style(expr, true)
}
pub(super) fn print_expr_outer_attr_style(&mut self, expr: &ast::Expr, is_inline: bool) {
self.maybe_print_comment(expr.span.lo());
let attrs = &expr.attrs;
if is_inline {
self.print_outer_attributes_inline(attrs);
} else {
self.print_outer_attributes(attrs);
}
self.ibox(INDENT_UNIT);
self.ann.pre(self, AnnNode::Expr(expr));
match &expr.kind {
ast::ExprKind::Array(exprs) => {
self.print_expr_vec(exprs);
}
ast::ExprKind::ConstBlock(anon_const) => {
self.print_expr_anon_const(anon_const, attrs);
}
ast::ExprKind::Repeat(element, count) => {
self.print_expr_repeat(element, count);
}
ast::ExprKind::Struct(se) => {
self.print_expr_struct(&se.qself, &se.path, &se.fields, &se.rest);
}
ast::ExprKind::Tup(exprs) => {
self.print_expr_tup(exprs);
}
ast::ExprKind::Call(func, args) => {
self.print_expr_call(func, args);
}
ast::ExprKind::MethodCall(box ast::MethodCall { seg, receiver, args, .. }) => {
self.print_expr_method_call(seg, receiver, args);
}
ast::ExprKind::Binary(op, lhs, rhs) => {
self.print_expr_binary(*op, lhs, rhs);
}
ast::ExprKind::Unary(op, expr) => {
self.print_expr_unary(*op, expr);
}
ast::ExprKind::AddrOf(k, m, expr) => {
self.print_expr_addr_of(*k, *m, expr);
}
ast::ExprKind::Lit(token_lit) => {
self.print_token_literal(*token_lit, expr.span);
}
ast::ExprKind::IncludedBytes(bytes) => {
let lit = token::Lit::new(token::ByteStr, escape_byte_str_symbol(bytes), None);
self.print_token_literal(lit, expr.span)
}
ast::ExprKind::Cast(expr, ty) => {
let prec = AssocOp::As.precedence() as i8;
self.print_expr_maybe_paren(expr, prec);
self.space();
self.word_space("as");
self.print_type(ty);
}
ast::ExprKind::Type(expr, ty) => {
self.word("type_ascribe!(");
self.ibox(0);
self.print_expr(expr);
self.word(",");
self.space_if_not_bol();
self.print_type(ty);
self.end();
self.word(")");
}
ast::ExprKind::Let(pat, scrutinee, _, _) => {
self.print_let(pat, scrutinee);
}
ast::ExprKind::If(test, blk, elseopt) => self.print_if(test, blk, elseopt.as_deref()),
ast::ExprKind::While(test, blk, opt_label) => {
if let Some(label) = opt_label {
self.print_ident(label.ident);
self.word_space(":");
}
self.cbox(0);
self.ibox(0);
self.word_nbsp("while");
self.print_expr_as_cond(test);
self.space();
self.print_block_with_attrs(blk, attrs);
}
ast::ExprKind::ForLoop(pat, iter, blk, opt_label) => {
if let Some(label) = opt_label {
self.print_ident(label.ident);
self.word_space(":");
}
self.cbox(0);
self.ibox(0);
self.word_nbsp("for");
self.print_pat(pat);
self.space();
self.word_space("in");
self.print_expr_as_cond(iter);
self.space();
self.print_block_with_attrs(blk, attrs);
}
ast::ExprKind::Loop(blk, opt_label, _) => {
if let Some(label) = opt_label {
self.print_ident(label.ident);
self.word_space(":");
}
self.cbox(0);
self.ibox(0);
self.word_nbsp("loop");
self.print_block_with_attrs(blk, attrs);
}
ast::ExprKind::Match(expr, arms) => {
self.cbox(0);
self.ibox(0);
self.word_nbsp("match");
self.print_expr_as_cond(expr);
self.space();
self.bopen();
self.print_inner_attributes_no_trailing_hardbreak(attrs);
for arm in arms {
self.print_arm(arm);
}
let empty = attrs.is_empty() && arms.is_empty();
self.bclose(expr.span, empty);
}
ast::ExprKind::Closure(box ast::Closure {
binder,
capture_clause,
constness,
asyncness,
movability,
fn_decl,
body,
fn_decl_span: _,
fn_arg_span: _,
}) => {
self.print_closure_binder(binder);
self.print_constness(*constness);
self.print_movability(*movability);
self.print_asyncness(*asyncness);
self.print_capture_clause(*capture_clause);
self.print_fn_params_and_ret(fn_decl, true);
self.space();
self.print_expr(body);
self.end(); self.ibox(0);
}
ast::ExprKind::Block(blk, opt_label) => {
if let Some(label) = opt_label {
self.print_ident(label.ident);
self.word_space(":");
}
self.cbox(0);
self.ibox(0);
self.print_block_with_attrs(blk, attrs);
}
ast::ExprKind::Async(capture_clause, blk) => {
self.word_nbsp("async");
self.print_capture_clause(*capture_clause);
self.cbox(0);
self.ibox(0);
self.print_block_with_attrs(blk, attrs);
}
ast::ExprKind::Await(expr, _) => {
self.print_expr_maybe_paren(expr, parser::PREC_POSTFIX);
self.word(".await");
}
ast::ExprKind::Assign(lhs, rhs, _) => {
let prec = AssocOp::Assign.precedence() as i8;
self.print_expr_maybe_paren(lhs, prec + 1);
self.space();
self.word_space("=");
self.print_expr_maybe_paren(rhs, prec);
}
ast::ExprKind::AssignOp(op, lhs, rhs) => {
let prec = AssocOp::Assign.precedence() as i8;
self.print_expr_maybe_paren(lhs, prec + 1);
self.space();
self.word(op.node.to_string());
self.word_space("=");
self.print_expr_maybe_paren(rhs, prec);
}
ast::ExprKind::Field(expr, ident) => {
self.print_expr_maybe_paren(expr, parser::PREC_POSTFIX);
self.word(".");
self.print_ident(*ident);
}
ast::ExprKind::Index(expr, index, _) => {
self.print_expr_maybe_paren(expr, parser::PREC_POSTFIX);
self.word("[");
self.print_expr(index);
self.word("]");
}
ast::ExprKind::Range(start, end, limits) => {
let fake_prec = AssocOp::LOr.precedence() as i8;
if let Some(e) = start {
self.print_expr_maybe_paren(e, fake_prec);
}
match limits {
ast::RangeLimits::HalfOpen => self.word(".."),
ast::RangeLimits::Closed => self.word("..="),
}
if let Some(e) = end {
self.print_expr_maybe_paren(e, fake_prec);
}
}
ast::ExprKind::Underscore => self.word("_"),
ast::ExprKind::Path(None, path) => self.print_path(path, true, 0),
ast::ExprKind::Path(Some(qself), path) => self.print_qpath(path, qself, true),
ast::ExprKind::Break(opt_label, opt_expr) => {
self.word("break");
if let Some(label) = opt_label {
self.space();
self.print_ident(label.ident);
}
if let Some(expr) = opt_expr {
self.space();
self.print_expr_maybe_paren(expr, parser::PREC_JUMP);
}
}
ast::ExprKind::Continue(opt_label) => {
self.word("continue");
if let Some(label) = opt_label {
self.space();
self.print_ident(label.ident);
}
}
ast::ExprKind::Ret(result) => {
self.word("return");
if let Some(expr) = result {
self.word(" ");
self.print_expr_maybe_paren(expr, parser::PREC_JUMP);
}
}
ast::ExprKind::Yeet(result) => {
self.word("do");
self.word(" ");
self.word("yeet");
if let Some(expr) = result {
self.word(" ");
self.print_expr_maybe_paren(expr, parser::PREC_JUMP);
}
}
ast::ExprKind::Become(result) => {
self.word("become");
self.word(" ");
self.print_expr_maybe_paren(result, parser::PREC_JUMP);
}
ast::ExprKind::InlineAsm(a) => {
self.word("asm!");
self.print_inline_asm(a);
}
ast::ExprKind::FormatArgs(fmt) => {
self.word("format_args!");
self.popen();
self.rbox(0, Inconsistent);
self.word(reconstruct_format_args_template_string(&fmt.template));
for arg in fmt.arguments.all_args() {
self.word_space(",");
self.print_expr(&arg.expr);
}
self.end();
self.pclose();
}
ast::ExprKind::OffsetOf(container, fields) => {
self.word("builtin # offset_of");
self.popen();
self.rbox(0, Inconsistent);
self.print_type(container);
self.word(",");
self.space();
if let Some((&first, rest)) = fields.split_first() {
self.print_ident(first);
for &field in rest {
self.word(".");
self.print_ident(field);
}
}
self.pclose();
self.end();
}
ast::ExprKind::MacCall(m) => self.print_mac(m),
ast::ExprKind::Paren(e) => {
self.popen();
self.print_expr(e);
self.pclose();
}
ast::ExprKind::Yield(e) => {
self.word("yield");
if let Some(expr) = e {
self.space();
self.print_expr_maybe_paren(expr, parser::PREC_JUMP);
}
}
ast::ExprKind::Try(e) => {
self.print_expr_maybe_paren(e, parser::PREC_POSTFIX);
self.word("?")
}
ast::ExprKind::TryBlock(blk) => {
self.cbox(0);
self.ibox(0);
self.word_nbsp("try");
self.print_block_with_attrs(blk, attrs)
}
ast::ExprKind::Err => {
self.popen();
self.word("/*ERROR*/");
self.pclose()
}
}
self.ann.post(self, AnnNode::Expr(expr));
self.end();
}
fn print_arm(&mut self, arm: &ast::Arm) {
if arm.attrs.is_empty() {
self.space();
}
self.cbox(INDENT_UNIT);
self.ibox(0);
self.maybe_print_comment(arm.pat.span.lo());
self.print_outer_attributes(&arm.attrs);
self.print_pat(&arm.pat);
self.space();
if let Some(e) = &arm.guard {
self.word_space("if");
self.print_expr(e);
self.space();
}
self.word_space("=>");
match &arm.body.kind {
ast::ExprKind::Block(blk, opt_label) => {
if let Some(label) = opt_label {
self.print_ident(label.ident);
self.word_space(":");
}
self.print_block_unclosed_indent(blk);
if let BlockCheckMode::Unsafe(ast::UserProvided) = blk.rules {
self.word(",");
}
}
_ => {
self.end(); self.print_expr(&arm.body);
self.word(",");
}
}
self.end(); }
fn print_closure_binder(&mut self, binder: &ast::ClosureBinder) {
match binder {
ast::ClosureBinder::NotPresent => {}
ast::ClosureBinder::For { generic_params, .. } => {
self.print_formal_generic_params(generic_params)
}
}
}
fn print_movability(&mut self, movability: ast::Movability) {
match movability {
ast::Movability::Static => self.word_space("static"),
ast::Movability::Movable => {}
}
}
fn print_capture_clause(&mut self, capture_clause: ast::CaptureBy) {
match capture_clause {
ast::CaptureBy::Value => self.word_space("move"),
ast::CaptureBy::Ref => {}
}
}
}
pub fn reconstruct_format_args_template_string(pieces: &[FormatArgsPiece]) -> String {
let mut template = "\"".to_string();
for piece in pieces {
match piece {
FormatArgsPiece::Literal(s) => {
for c in s.as_str().escape_debug() {
template.push(c);
if let '{' | '}' = c {
template.push(c);
}
}
}
FormatArgsPiece::Placeholder(p) => {
template.push('{');
let (Ok(n) | Err(n)) = p.argument.index;
write!(template, "{n}").unwrap();
if p.format_options != Default::default() || p.format_trait != FormatTrait::Display
{
template.push(':');
}
if let Some(fill) = p.format_options.fill {
template.push(fill);
}
match p.format_options.alignment {
Some(FormatAlignment::Left) => template.push('<'),
Some(FormatAlignment::Right) => template.push('>'),
Some(FormatAlignment::Center) => template.push('^'),
None => {}
}
match p.format_options.sign {
Some(FormatSign::Plus) => template.push('+'),
Some(FormatSign::Minus) => template.push('-'),
None => {}
}
if p.format_options.alternate {
template.push('#');
}
if p.format_options.zero_pad {
template.push('0');
}
if let Some(width) = &p.format_options.width {
match width {
FormatCount::Literal(n) => write!(template, "{n}").unwrap(),
FormatCount::Argument(FormatArgPosition {
index: Ok(n) | Err(n), ..
}) => {
write!(template, "{n}$").unwrap();
}
}
}
if let Some(precision) = &p.format_options.precision {
template.push('.');
match precision {
FormatCount::Literal(n) => write!(template, "{n}").unwrap(),
FormatCount::Argument(FormatArgPosition {
index: Ok(n) | Err(n), ..
}) => {
write!(template, "{n}$").unwrap();
}
}
}
match p.format_options.debug_hex {
Some(FormatDebugHex::Lower) => template.push('x'),
Some(FormatDebugHex::Upper) => template.push('X'),
None => {}
}
template.push_str(match p.format_trait {
FormatTrait::Display => "",
FormatTrait::Debug => "?",
FormatTrait::LowerExp => "e",
FormatTrait::UpperExp => "E",
FormatTrait::Octal => "o",
FormatTrait::Pointer => "p",
FormatTrait::Binary => "b",
FormatTrait::LowerHex => "x",
FormatTrait::UpperHex => "X",
});
template.push('}');
}
}
}
template.push('"');
template
}