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|
use super::*;
mod consts;
mod structs;
mod traits;
mod use_item;
// test mod_contents
// fn foo() {}
// macro_rules! foo {}
// foo::bar!();
// super::baz! {}
// struct S;
pub(super) fn mod_contents(p: &mut Parser, stop_on_r_curly: bool) {
attributes::inner_attributes(p);
while !p.at(EOF) && !(stop_on_r_curly && p.at(R_CURLY)) {
item_or_macro(p, stop_on_r_curly)
}
}
pub(super) fn item_or_macro(p: &mut Parser, stop_on_r_curly: bool) {
let m = p.start();
match maybe_item(p) {
MaybeItem::Item(kind) => {
m.complete(p, kind);
}
MaybeItem::None => {
if paths::is_path_start(p) {
match macro_call(p) {
MacroFlavor::Curly => (),
MacroFlavor::NonCurly => {
p.expect(SEMI);
}
}
m.complete(p, MACRO_CALL);
} else {
m.abandon(p);
if p.at(L_CURLY) {
error_block(p, "expected an item");
} else if !p.at(EOF) && !(stop_on_r_curly && p.at(R_CURLY)) {
p.err_and_bump("expected an item");
} else {
p.error("expected an item");
}
}
}
MaybeItem::Modifiers => {
p.error("expected fn, trait or impl");
m.complete(p, ERROR);
}
}
}
pub(super) const ITEM_FIRST: TokenSet =
token_set![EXTERN_KW, MOD_KW, USE_KW, STRUCT_KW, ENUM_KW, FN_KW, PUB_KW, POUND];
pub(super) enum MaybeItem {
None,
Item(SyntaxKind),
Modifiers,
}
pub(super) fn maybe_item(p: &mut Parser) -> MaybeItem {
attributes::outer_attributes(p);
visibility(p);
if let Some(kind) = items_without_modifiers(p) {
return MaybeItem::Item(kind);
}
let mut has_mods = false;
// modifiers
has_mods |= p.eat(CONST_KW);
// test unsafe_block_in_mod
// fn foo(){} unsafe { } fn bar(){}
if p.at(UNSAFE_KW) && p.nth(1) != L_CURLY {
p.eat(UNSAFE_KW);
has_mods = true;
}
if p.at(EXTERN_KW) {
has_mods = true;
abi(p);
}
if p.at(IDENT) && p.at_contextual_kw("auto") && p.nth(1) == TRAIT_KW {
p.bump_remap(AUTO_KW);
has_mods = true;
}
if p.at(IDENT) && p.at_contextual_kw("default") && p.nth(1) == IMPL_KW {
p.bump_remap(DEFAULT_KW);
has_mods = true;
}
// items
let kind = match p.current() {
// test extern_fn
// extern fn foo() {}
// test const_fn
// const fn foo() {}
// test const_unsafe_fn
// const unsafe fn foo() {}
// test unsafe_extern_fn
// unsafe extern "C" fn foo() {}
// test unsafe_fn
// unsafe fn foo() {}
FN_KW => {
fn_item(p);
FN_ITEM
}
// test unsafe_trait
// unsafe trait T {}
// test auto_trait
// auto trait T {}
// test unsafe_auto_trait
// unsafe auto trait T {}
TRAIT_KW => {
traits::trait_item(p);
TRAIT_ITEM
}
// test unsafe_impl
// unsafe impl Foo {}
// test default_impl
// default impl Foo {}
// test unsafe_default_impl
// unsafe default impl Foo {}
IMPL_KW => {
traits::impl_item(p);
IMPL_ITEM
}
_ => return if has_mods {
MaybeItem::Modifiers
} else {
MaybeItem::None
}
};
MaybeItem::Item(kind)
}
fn items_without_modifiers(p: &mut Parser) -> Option<SyntaxKind> {
let la = p.nth(1);
let kind = match p.current() {
// test extern_crate
// extern crate foo;
EXTERN_KW if la == CRATE_KW => {
extern_crate_item(p);
EXTERN_CRATE_ITEM
}
TYPE_KW => {
type_item(p);
TYPE_ITEM
}
MOD_KW => {
mod_item(p);
MOD_ITEM
}
STRUCT_KW => {
structs::struct_item(p);
if p.at(SEMI) {
p.err_and_bump(
"expected item, found `;`\n\
consider removing this semicolon"
);
}
STRUCT_ITEM
}
ENUM_KW => {
structs::enum_item(p);
ENUM_ITEM
}
USE_KW => {
use_item::use_item(p);
USE_ITEM
}
CONST_KW if (la == IDENT || la == MUT_KW) => {
consts::const_item(p);
CONST_ITEM
}
STATIC_KW => {
consts::static_item(p);
STATIC_ITEM
}
// test extern_block
// extern {}
EXTERN_KW if la == L_CURLY || ((la == STRING || la == RAW_STRING) && p.nth(2) == L_CURLY) => {
abi(p);
extern_block(p);
EXTERN_BLOCK_EXPR
}
_ => return None,
};
Some(kind)
}
fn extern_crate_item(p: &mut Parser) {
assert!(p.at(EXTERN_KW));
p.bump();
assert!(p.at(CRATE_KW));
p.bump();
name(p);
alias(p);
p.expect(SEMI);
}
fn extern_block(p: &mut Parser) {
assert!(p.at(L_CURLY));
p.bump();
p.expect(R_CURLY);
}
fn fn_item(p: &mut Parser) {
assert!(p.at(FN_KW));
p.bump();
name(p);
// test fn_item_type_params
// fn foo<T: Clone + Copy>(){}
type_params::type_param_list(p);
if p.at(L_PAREN) {
params::param_list(p);
} else {
p.error("expected function arguments");
}
// test fn_item_ret_type
// fn foo() {}
// fn bar() -> () {}
fn_ret_type(p);
// test fn_item_where_clause
// fn foo<T>() where T: Copy {}
type_params::where_clause(p);
expressions::block(p);
}
// test type_item
// type Foo = Bar;
fn type_item(p: &mut Parser) {
assert!(p.at(TYPE_KW));
p.bump();
name(p);
// test type_item_type_params
// type Result<T> = ();
type_params::type_param_list(p);
// test type_item_where_clause
// type Foo where Foo: Copy = ();
type_params::where_clause(p);
p.expect(EQ);
types::type_(p);
p.expect(SEMI);
}
fn mod_item(p: &mut Parser) {
assert!(p.at(MOD_KW));
p.bump();
name(p);
if !p.eat(SEMI) {
if p.expect(L_CURLY) {
mod_contents(p, true);
p.expect(R_CURLY);
}
}
}
enum MacroFlavor {
Curly,
NonCurly,
}
fn macro_call(p: &mut Parser) -> MacroFlavor {
assert!(paths::is_path_start(p));
paths::use_path(p);
p.expect(EXCL);
p.eat(IDENT);
let flavor = match p.current() {
L_CURLY => {
token_tree(p);
MacroFlavor::Curly
}
L_PAREN | L_BRACK => {
token_tree(p);
MacroFlavor::NonCurly
}
_ => {
p.error("expected `{`, `[`, `(`");
MacroFlavor::NonCurly
},
};
flavor
}
fn token_tree(p: &mut Parser) {
let closing_paren_kind = match p.current() {
L_CURLY => R_CURLY,
L_PAREN => R_PAREN,
L_BRACK => R_BRACK,
_ => unreachable!(),
};
p.bump();
while !p.at(EOF) && !p.at(closing_paren_kind) {
match p.current() {
L_CURLY | L_PAREN | L_BRACK => token_tree(p),
R_CURLY | R_PAREN | R_BRACK => p.err_and_bump("unmatched brace"),
_ => p.bump()
}
};
p.expect(closing_paren_kind);
}
|