bendns' repos / rust-analyzer
Unnamed repository; edit this file 'description' to name the repository.
Diffstat (limited to 'crates/parser/src/grammar/items/use_item.rs')
-rw-r--r--crates/parser/src/grammar/items/use_item.rs93
1 files changed, 28 insertions, 65 deletions
diff --git a/crates/parser/src/grammar/items/use_item.rs b/crates/parser/src/grammar/items/use_item.rs
index 2339d0c69c..ffb147b1fd 100644
--- a/crates/parser/src/grammar/items/use_item.rs
+++ b/crates/parser/src/grammar/items/use_item.rs
@@ -1,99 +1,60 @@
use super::*;
+// test use_item
+// use std::collections;
pub(super) fn use_(p: &mut Parser, m: Marker) {
- assert!(p.at(T![use]));
p.bump(T![use]);
use_tree(p, true);
p.expect(T![;]);
m.complete(p, USE);
}
-/// Parse a use 'tree', such as `some::path` in `use some::path;`
-/// Note that this is called both by `use_item` and `use_tree_list`,
-/// so handles both `some::path::{inner::path}` and `inner::path` in
-/// `use some::path::{inner::path};`
+// test use_tree
+// use outer::tree::{inner::tree};
fn use_tree(p: &mut Parser, top_level: bool) {
let m = p.start();
match p.current() {
- // Finish the use_tree for cases of e.g.
- // `use some::path::{self, *};` or `use *;`
- // This does not handle cases such as `use some::path::*`
- // N.B. in Rust 2015 `use *;` imports all from crate root
- // however in Rust 2018 `use *;` errors: ('cannot glob-import all possible crates')
- // FIXME: Add this error (if not out of scope)
-
- // test use_star
+ // test use_tree_star
// use *;
- // use ::*;
- // use some::path::{*};
- // use some::path::{::*};
+ // use std::{*};
T![*] => p.bump(T![*]),
+ // test use_tree_abs_star
+ // use ::*;
+ // use std::{::*};
T![:] if p.at(T![::]) && p.nth(2) == T![*] => {
- // Parse `use ::*;`, which imports all from the crate root in Rust 2015
- // This is invalid inside a use_tree_list, (e.g. `use some::path::{::*}`)
- // but still parses and errors later: ('crate root in paths can only be used in start position')
- // FIXME: Add this error (if not out of scope)
- // In Rust 2018, it is always invalid (see above)
p.bump(T![::]);
p.bump(T![*]);
}
- // Open a use tree list
- // Handles cases such as `use {some::path};` or `{inner::path}` in
- // `use some::path::{{inner::path}, other::path}`
-
- // test use_tree_list
- // use {crate::path::from::root, or::path::from::crate_name}; // Rust 2018 (with a crate named `or`)
- // use {path::from::root}; // Rust 2015
- // use ::{some::arbitrary::path}; // Rust 2015
- // use ::{{{root::export}}}; // Nonsensical but perfectly legal nesting
- T!['{'] => {
- use_tree_list(p);
- }
+ T!['{'] => use_tree_list(p),
T![:] if p.at(T![::]) && p.nth(2) == T!['{'] => {
p.bump(T![::]);
use_tree_list(p);
}
- // Parse a 'standard' path.
- // Also handles aliases (e.g. `use something as something_else`)
- // test use_path
- // use ::crate_name; // Rust 2018 - All flavours
- // use crate_name; // Rust 2018 - Anchored paths
- // use item_in_scope_or_crate_name; // Rust 2018 - Uniform Paths
+ // test use_tree_path
+ // use ::std;
+ // use std::collections;
//
- // use self::module::Item;
- // use crate::Item;
- // use self::some::Struct;
- // use crate_name::some_item;
+ // use self::m;
+ // use super::m;
+ // use crate::m;
_ if paths::is_use_path_start(p) => {
paths::use_path(p);
match p.current() {
- T![as] => {
- // test use_alias
- // use some::path as some_name;
- // use some::{
- // other::path as some_other_name,
- // different::path as different_name,
- // yet::another::path,
- // running::out::of::synonyms::for_::different::*
- // };
- // use Trait as _;
- opt_rename(p);
- }
+ // test use_tree_alias
+ // use std as stdlib;
+ // use Trait as _;
+ T![as] => opt_rename(p),
T![:] if p.at(T![::]) => {
p.bump(T![::]);
match p.current() {
- T![*] => {
- p.bump(T![*]);
- }
- // test use_tree_list_after_path
- // use crate::{Item};
- // use self::{Item};
+ // test use_tree_path_star
+ // use std::*;
+ T![*] => p.bump(T![*]),
+ // test use_tree_path_use_tree
+ // use std::{collections};
T!['{'] => use_tree_list(p),
- _ => {
- // is this unreachable?
- p.error("expected `{` or `*`");
- }
+ _ => p.error("expected `{` or `*`"),
}
}
_ => (),
@@ -115,6 +76,8 @@ fn use_tree(p: &mut Parser, top_level: bool) {
m.complete(p, USE_TREE);
}
+// test use_tree_list
+// use {a, b, c};
pub(crate) fn use_tree_list(p: &mut Parser) {
assert!(p.at(T!['{']));
let m = p.start();