rust/crates/ide_assists/src/handlers/auto_import.rs
2021-07-06 20:30:26 +02:00

1002 lines
24 KiB
Rust

use ide_db::helpers::{
import_assets::{ImportAssets, ImportCandidate},
insert_use::{insert_use, ImportScope},
mod_path_to_ast,
};
use syntax::{ast, AstNode, SyntaxNode};
use crate::{AssistContext, AssistId, AssistKind, Assists, GroupLabel};
// Feature: Auto Import
//
// Using the `auto-import` assist it is possible to insert missing imports for unresolved items.
// When inserting an import it will do so in a structured manner by keeping imports grouped,
// separated by a newline in the following order:
//
// - `std` and `core`
// - External Crates
// - Current Crate, paths prefixed by `crate`
// - Current Module, paths prefixed by `self`
// - Super Module, paths prefixed by `super`
//
// Example:
// ```rust
// use std::fs::File;
//
// use itertools::Itertools;
// use syntax::ast;
//
// use crate::utils::insert_use;
//
// use self::auto_import;
//
// use super::AssistContext;
// ```
//
// .Import Granularity
//
// It is possible to configure how use-trees are merged with the `importGranularity` setting.
// It has the following configurations:
//
// - `crate`: Merge imports from the same crate into a single use statement. This kind of
// nesting is only supported in Rust versions later than 1.24.
// - `module`: Merge imports from the same module into a single use statement.
// - `item`: Don't merge imports at all, creating one import per item.
// - `preserve`: Do not change the granularity of any imports. For auto-import this has the same
// effect as `item`.
//
// In `VS Code` the configuration for this is `rust-analyzer.assist.importGranularity`.
//
// .Import Prefix
//
// The style of imports in the same crate is configurable through the `importPrefix` setting.
// It has the following configurations:
//
// - `by_crate`: This setting will force paths to be always absolute, starting with the `crate`
// prefix, unless the item is defined outside of the current crate.
// - `by_self`: This setting will force paths that are relative to the current module to always
// start with `self`. This will result in paths that always start with either `crate`, `self`,
// `super` or an extern crate identifier.
// - `plain`: This setting does not impose any restrictions in imports.
//
// In `VS Code` the configuration for this is `rust-analyzer.assist.importPrefix`.
//
// image::https://user-images.githubusercontent.com/48062697/113020673-b85be580-917a-11eb-9022-59585f35d4f8.gif[]
// Assist: auto_import
//
// If the name is unresolved, provides all possible imports for it.
//
// ```
// fn main() {
// let map = HashMap$0::new();
// }
// # pub mod std { pub mod collections { pub struct HashMap { } } }
// ```
// ->
// ```
// use std::collections::HashMap;
//
// fn main() {
// let map = HashMap::new();
// }
// # pub mod std { pub mod collections { pub struct HashMap { } } }
// ```
pub(crate) fn auto_import(acc: &mut Assists, ctx: &AssistContext) -> Option<()> {
let (import_assets, syntax_under_caret) = find_importable_node(ctx)?;
let mut proposed_imports =
import_assets.search_for_imports(&ctx.sema, ctx.config.insert_use.prefix_kind);
if proposed_imports.is_empty() {
return None;
}
// we aren't interested in different namespaces
proposed_imports.dedup_by(|a, b| a.import_path == b.import_path);
let range = ctx.sema.original_range(&syntax_under_caret).range;
let group_label = group_label(import_assets.import_candidate());
let scope = ImportScope::find_insert_use_container_with_macros(&syntax_under_caret, &ctx.sema)?;
for import in proposed_imports {
acc.add_group(
&group_label,
AssistId("auto_import", AssistKind::QuickFix),
format!("Import `{}`", import.import_path),
range,
|builder| {
let scope = match scope.clone() {
ImportScope::File(it) => ImportScope::File(builder.make_mut(it)),
ImportScope::Module(it) => ImportScope::Module(builder.make_mut(it)),
ImportScope::Block(it) => ImportScope::Block(builder.make_mut(it)),
};
insert_use(&scope, mod_path_to_ast(&import.import_path), &ctx.config.insert_use);
},
);
}
Some(())
}
pub(super) fn find_importable_node(ctx: &AssistContext) -> Option<(ImportAssets, SyntaxNode)> {
if let Some(path_under_caret) = ctx.find_node_at_offset_with_descend::<ast::Path>() {
ImportAssets::for_exact_path(&path_under_caret, &ctx.sema)
.zip(Some(path_under_caret.syntax().clone()))
} else if let Some(method_under_caret) =
ctx.find_node_at_offset_with_descend::<ast::MethodCallExpr>()
{
ImportAssets::for_method_call(&method_under_caret, &ctx.sema)
.zip(Some(method_under_caret.syntax().clone()))
} else {
None
}
}
fn group_label(import_candidate: &ImportCandidate) -> GroupLabel {
let name = match import_candidate {
ImportCandidate::Path(candidate) => format!("Import {}", candidate.name.text()),
ImportCandidate::TraitAssocItem(candidate) => {
format!("Import a trait for item {}", candidate.assoc_item_name.text())
}
ImportCandidate::TraitMethod(candidate) => {
format!("Import a trait for method {}", candidate.assoc_item_name.text())
}
};
GroupLabel(name)
}
#[cfg(test)]
mod tests {
use super::*;
use crate::tests::{check_assist, check_assist_not_applicable, check_assist_target};
#[test]
fn applicable_when_found_an_import_partial() {
check_assist(
auto_import,
r"
mod std {
pub mod fmt {
pub struct Formatter;
}
}
use std::fmt;
$0Formatter
",
r"
mod std {
pub mod fmt {
pub struct Formatter;
}
}
use std::fmt::{self, Formatter};
Formatter
",
);
}
#[test]
fn applicable_when_found_an_import() {
check_assist(
auto_import,
r"
$0PubStruct
pub mod PubMod {
pub struct PubStruct;
}
",
r"
use PubMod::PubStruct;
PubStruct
pub mod PubMod {
pub struct PubStruct;
}
",
);
}
#[test]
fn applicable_when_found_an_import_in_macros() {
check_assist(
auto_import,
r"
macro_rules! foo {
($i:ident) => { fn foo(a: $i) {} }
}
foo!(Pub$0Struct);
pub mod PubMod {
pub struct PubStruct;
}
",
r"
use PubMod::PubStruct;
macro_rules! foo {
($i:ident) => { fn foo(a: $i) {} }
}
foo!(PubStruct);
pub mod PubMod {
pub struct PubStruct;
}
",
);
}
#[test]
fn applicable_when_found_multiple_imports() {
check_assist(
auto_import,
r"
PubSt$0ruct
pub mod PubMod1 {
pub struct PubStruct;
}
pub mod PubMod2 {
pub struct PubStruct;
}
pub mod PubMod3 {
pub struct PubStruct;
}
",
r"
use PubMod3::PubStruct;
PubStruct
pub mod PubMod1 {
pub struct PubStruct;
}
pub mod PubMod2 {
pub struct PubStruct;
}
pub mod PubMod3 {
pub struct PubStruct;
}
",
);
}
#[test]
fn not_applicable_for_already_imported_types() {
check_assist_not_applicable(
auto_import,
r"
use PubMod::PubStruct;
PubStruct$0
pub mod PubMod {
pub struct PubStruct;
}
",
);
}
#[test]
fn not_applicable_for_types_with_private_paths() {
check_assist_not_applicable(
auto_import,
r"
PrivateStruct$0
pub mod PubMod {
struct PrivateStruct;
}
",
);
}
#[test]
fn not_applicable_when_no_imports_found() {
check_assist_not_applicable(
auto_import,
"
PubStruct$0",
);
}
#[test]
fn not_applicable_in_import_statements() {
check_assist_not_applicable(
auto_import,
r"
use PubStruct$0;
pub mod PubMod {
pub struct PubStruct;
}",
);
}
#[test]
fn function_import() {
check_assist(
auto_import,
r"
test_function$0
pub mod PubMod {
pub fn test_function() {};
}
",
r"
use PubMod::test_function;
test_function
pub mod PubMod {
pub fn test_function() {};
}
",
);
}
#[test]
fn macro_import() {
check_assist(
auto_import,
r"
//- /lib.rs crate:crate_with_macro
#[macro_export]
macro_rules! foo {
() => ()
}
//- /main.rs crate:main deps:crate_with_macro
fn main() {
foo$0
}
",
r"use crate_with_macro::foo;
fn main() {
foo
}
",
);
}
#[test]
fn auto_import_target() {
check_assist_target(
auto_import,
r"
struct AssistInfo {
group_label: Option<$0GroupLabel>,
}
mod m { pub struct GroupLabel; }
",
"GroupLabel",
)
}
#[test]
fn not_applicable_when_path_start_is_imported() {
check_assist_not_applicable(
auto_import,
r"
pub mod mod1 {
pub mod mod2 {
pub mod mod3 {
pub struct TestStruct;
}
}
}
use mod1::mod2;
fn main() {
mod2::mod3::TestStruct$0
}
",
);
}
#[test]
fn not_applicable_for_imported_function() {
check_assist_not_applicable(
auto_import,
r"
pub mod test_mod {
pub fn test_function() {}
}
use test_mod::test_function;
fn main() {
test_function$0
}
",
);
}
#[test]
fn associated_struct_function() {
check_assist(
auto_import,
r"
mod test_mod {
pub struct TestStruct {}
impl TestStruct {
pub fn test_function() {}
}
}
fn main() {
TestStruct::test_function$0
}
",
r"
use test_mod::TestStruct;
mod test_mod {
pub struct TestStruct {}
impl TestStruct {
pub fn test_function() {}
}
}
fn main() {
TestStruct::test_function
}
",
);
}
#[test]
fn associated_struct_const() {
check_assist(
auto_import,
r"
mod test_mod {
pub struct TestStruct {}
impl TestStruct {
const TEST_CONST: u8 = 42;
}
}
fn main() {
TestStruct::TEST_CONST$0
}
",
r"
use test_mod::TestStruct;
mod test_mod {
pub struct TestStruct {}
impl TestStruct {
const TEST_CONST: u8 = 42;
}
}
fn main() {
TestStruct::TEST_CONST
}
",
);
}
#[test]
fn associated_trait_function() {
check_assist(
auto_import,
r"
mod test_mod {
pub trait TestTrait {
fn test_function();
}
pub struct TestStruct {}
impl TestTrait for TestStruct {
fn test_function() {}
}
}
fn main() {
test_mod::TestStruct::test_function$0
}
",
r"
use test_mod::TestTrait;
mod test_mod {
pub trait TestTrait {
fn test_function();
}
pub struct TestStruct {}
impl TestTrait for TestStruct {
fn test_function() {}
}
}
fn main() {
test_mod::TestStruct::test_function
}
",
);
}
#[test]
fn not_applicable_for_imported_trait_for_function() {
check_assist_not_applicable(
auto_import,
r"
mod test_mod {
pub trait TestTrait {
fn test_function();
}
pub trait TestTrait2 {
fn test_function();
}
pub enum TestEnum {
One,
Two,
}
impl TestTrait2 for TestEnum {
fn test_function() {}
}
impl TestTrait for TestEnum {
fn test_function() {}
}
}
use test_mod::TestTrait2;
fn main() {
test_mod::TestEnum::test_function$0;
}
",
)
}
#[test]
fn associated_trait_const() {
check_assist(
auto_import,
r"
mod test_mod {
pub trait TestTrait {
const TEST_CONST: u8;
}
pub struct TestStruct {}
impl TestTrait for TestStruct {
const TEST_CONST: u8 = 42;
}
}
fn main() {
test_mod::TestStruct::TEST_CONST$0
}
",
r"
use test_mod::TestTrait;
mod test_mod {
pub trait TestTrait {
const TEST_CONST: u8;
}
pub struct TestStruct {}
impl TestTrait for TestStruct {
const TEST_CONST: u8 = 42;
}
}
fn main() {
test_mod::TestStruct::TEST_CONST
}
",
);
}
#[test]
fn not_applicable_for_imported_trait_for_const() {
check_assist_not_applicable(
auto_import,
r"
mod test_mod {
pub trait TestTrait {
const TEST_CONST: u8;
}
pub trait TestTrait2 {
const TEST_CONST: f64;
}
pub enum TestEnum {
One,
Two,
}
impl TestTrait2 for TestEnum {
const TEST_CONST: f64 = 42.0;
}
impl TestTrait for TestEnum {
const TEST_CONST: u8 = 42;
}
}
use test_mod::TestTrait2;
fn main() {
test_mod::TestEnum::TEST_CONST$0;
}
",
)
}
#[test]
fn trait_method() {
check_assist(
auto_import,
r"
mod test_mod {
pub trait TestTrait {
fn test_method(&self);
}
pub struct TestStruct {}
impl TestTrait for TestStruct {
fn test_method(&self) {}
}
}
fn main() {
let test_struct = test_mod::TestStruct {};
test_struct.test_meth$0od()
}
",
r"
use test_mod::TestTrait;
mod test_mod {
pub trait TestTrait {
fn test_method(&self);
}
pub struct TestStruct {}
impl TestTrait for TestStruct {
fn test_method(&self) {}
}
}
fn main() {
let test_struct = test_mod::TestStruct {};
test_struct.test_method()
}
",
);
}
#[test]
fn trait_method_cross_crate() {
check_assist(
auto_import,
r"
//- /main.rs crate:main deps:dep
fn main() {
let test_struct = dep::test_mod::TestStruct {};
test_struct.test_meth$0od()
}
//- /dep.rs crate:dep
pub mod test_mod {
pub trait TestTrait {
fn test_method(&self);
}
pub struct TestStruct {}
impl TestTrait for TestStruct {
fn test_method(&self) {}
}
}
",
r"
use dep::test_mod::TestTrait;
fn main() {
let test_struct = dep::test_mod::TestStruct {};
test_struct.test_method()
}
",
);
}
#[test]
fn assoc_fn_cross_crate() {
check_assist(
auto_import,
r"
//- /main.rs crate:main deps:dep
fn main() {
dep::test_mod::TestStruct::test_func$0tion
}
//- /dep.rs crate:dep
pub mod test_mod {
pub trait TestTrait {
fn test_function();
}
pub struct TestStruct {}
impl TestTrait for TestStruct {
fn test_function() {}
}
}
",
r"
use dep::test_mod::TestTrait;
fn main() {
dep::test_mod::TestStruct::test_function
}
",
);
}
#[test]
fn assoc_const_cross_crate() {
check_assist(
auto_import,
r"
//- /main.rs crate:main deps:dep
fn main() {
dep::test_mod::TestStruct::CONST$0
}
//- /dep.rs crate:dep
pub mod test_mod {
pub trait TestTrait {
const CONST: bool;
}
pub struct TestStruct {}
impl TestTrait for TestStruct {
const CONST: bool = true;
}
}
",
r"
use dep::test_mod::TestTrait;
fn main() {
dep::test_mod::TestStruct::CONST
}
",
);
}
#[test]
fn assoc_fn_as_method_cross_crate() {
check_assist_not_applicable(
auto_import,
r"
//- /main.rs crate:main deps:dep
fn main() {
let test_struct = dep::test_mod::TestStruct {};
test_struct.test_func$0tion()
}
//- /dep.rs crate:dep
pub mod test_mod {
pub trait TestTrait {
fn test_function();
}
pub struct TestStruct {}
impl TestTrait for TestStruct {
fn test_function() {}
}
}
",
);
}
#[test]
fn private_trait_cross_crate() {
check_assist_not_applicable(
auto_import,
r"
//- /main.rs crate:main deps:dep
fn main() {
let test_struct = dep::test_mod::TestStruct {};
test_struct.test_meth$0od()
}
//- /dep.rs crate:dep
pub mod test_mod {
trait TestTrait {
fn test_method(&self);
}
pub struct TestStruct {}
impl TestTrait for TestStruct {
fn test_method(&self) {}
}
}
",
);
}
#[test]
fn not_applicable_for_imported_trait_for_method() {
check_assist_not_applicable(
auto_import,
r"
mod test_mod {
pub trait TestTrait {
fn test_method(&self);
}
pub trait TestTrait2 {
fn test_method(&self);
}
pub enum TestEnum {
One,
Two,
}
impl TestTrait2 for TestEnum {
fn test_method(&self) {}
}
impl TestTrait for TestEnum {
fn test_method(&self) {}
}
}
use test_mod::TestTrait2;
fn main() {
let one = test_mod::TestEnum::One;
one.test$0_method();
}
",
)
}
#[test]
fn dep_import() {
check_assist(
auto_import,
r"
//- /lib.rs crate:dep
pub struct Struct;
//- /main.rs crate:main deps:dep
fn main() {
Struct$0
}
",
r"use dep::Struct;
fn main() {
Struct
}
",
);
}
#[test]
fn whole_segment() {
// Tests that only imports whose last segment matches the identifier get suggested.
check_assist(
auto_import,
r"
//- /lib.rs crate:dep
pub mod fmt {
pub trait Display {}
}
pub fn panic_fmt() {}
//- /main.rs crate:main deps:dep
struct S;
impl f$0mt::Display for S {}
",
r"use dep::fmt;
struct S;
impl fmt::Display for S {}
",
);
}
#[test]
fn macro_generated() {
// Tests that macro-generated items are suggested from external crates.
check_assist(
auto_import,
r"
//- /lib.rs crate:dep
macro_rules! mac {
() => {
pub struct Cheese;
};
}
mac!();
//- /main.rs crate:main deps:dep
fn main() {
Cheese$0;
}
",
r"use dep::Cheese;
fn main() {
Cheese;
}
",
);
}
#[test]
fn casing() {
// Tests that differently cased names don't interfere and we only suggest the matching one.
check_assist(
auto_import,
r"
//- /lib.rs crate:dep
pub struct FMT;
pub struct fmt;
//- /main.rs crate:main deps:dep
fn main() {
FMT$0;
}
",
r"use dep::FMT;
fn main() {
FMT;
}
",
);
}
#[test]
fn inner_items() {
check_assist(
auto_import,
r#"
mod baz {
pub struct Foo {}
}
mod bar {
fn bar() {
Foo$0;
println!("Hallo");
}
}
"#,
r#"
mod baz {
pub struct Foo {}
}
mod bar {
use crate::baz::Foo;
fn bar() {
Foo;
println!("Hallo");
}
}
"#,
);
}
#[test]
fn uses_abs_path_with_extern_crate_clash() {
check_assist(
auto_import,
r#"
//- /main.rs crate:main deps:foo
mod foo {}
const _: () = {
Foo$0
};
//- /foo.rs crate:foo
pub struct Foo
"#,
r#"
use ::foo::Foo;
mod foo {}
const _: () = {
Foo
};
"#,
);
}
}