rust-analyzer/crates/ra_analysis/src/completion.rs
2018-12-08 19:30:35 +03:00

443 lines
16 KiB
Rust

mod reference_completion;
use ra_editor::find_node_at_offset;
use ra_syntax::{
algo::visit::{visitor_ctx, VisitorCtx},
ast,
AstNode, AtomEdit,
SyntaxNodeRef,
};
use ra_db::SyntaxDatabase;
use rustc_hash::{FxHashMap};
use hir::source_binder;
use crate::{
db,
Cancelable, FilePosition
};
#[derive(Debug)]
pub struct CompletionItem {
/// What user sees in pop-up
pub label: String,
/// What string is used for filtering, defaults to label
pub lookup: Option<String>,
/// What is inserted, defaults to label
pub snippet: Option<String>,
}
pub(crate) fn completions(
db: &db::RootDatabase,
position: FilePosition,
) -> Cancelable<Option<Vec<CompletionItem>>> {
let original_file = db.source_file(position.file_id);
// Insert a fake ident to get a valid parse tree
let file = {
let edit = AtomEdit::insert(position.offset, "intellijRulezz".to_string());
original_file.reparse(&edit)
};
let module = ctry!(source_binder::module_from_position(db, position)?);
let mut res = Vec::new();
let mut has_completions = false;
// First, let's try to complete a reference to some declaration.
if let Some(name_ref) = find_node_at_offset::<ast::NameRef>(file.syntax(), position.offset) {
has_completions = true;
reference_completion::completions(&mut res, db, &module, &file, name_ref)?;
// special case, `trait T { fn foo(i_am_a_name_ref) {} }`
if is_node::<ast::Param>(name_ref.syntax()) {
param_completions(name_ref.syntax(), &mut res);
}
}
// Otherwise, if this is a declaration, use heuristics to suggest a name.
if let Some(name) = find_node_at_offset::<ast::Name>(file.syntax(), position.offset) {
if is_node::<ast::Param>(name.syntax()) {
has_completions = true;
param_completions(name.syntax(), &mut res);
}
}
let res = if has_completions { Some(res) } else { None };
Ok(res)
}
fn param_completions(ctx: SyntaxNodeRef, acc: &mut Vec<CompletionItem>) {
let mut params = FxHashMap::default();
for node in ctx.ancestors() {
let _ = visitor_ctx(&mut params)
.visit::<ast::SourceFile, _>(process)
.visit::<ast::ItemList, _>(process)
.accept(node);
}
params
.into_iter()
.filter_map(|(label, (count, param))| {
let lookup = param.pat()?.syntax().text().to_string();
if count < 2 {
None
} else {
Some((label, lookup))
}
})
.for_each(|(label, lookup)| {
acc.push(CompletionItem {
label,
lookup: Some(lookup),
snippet: None,
})
});
fn process<'a, N: ast::FnDefOwner<'a>>(
node: N,
params: &mut FxHashMap<String, (u32, ast::Param<'a>)>,
) {
node.functions()
.filter_map(|it| it.param_list())
.flat_map(|it| it.params())
.for_each(|param| {
let text = param.syntax().text().to_string();
params.entry(text).or_insert((0, param)).0 += 1;
})
}
}
fn is_node<'a, N: AstNode<'a>>(node: SyntaxNodeRef<'a>) -> bool {
match node.ancestors().filter_map(N::cast).next() {
None => false,
Some(n) => n.syntax().range() == node.range(),
}
}
#[cfg(test)]
mod tests {
use test_utils::assert_eq_dbg;
use crate::mock_analysis::single_file_with_position;
use super::*;
fn check_scope_completion(code: &str, expected_completions: &str) {
let (analysis, position) = single_file_with_position(code);
let completions = completions(&analysis.imp.db, position)
.unwrap()
.unwrap()
.into_iter()
.filter(|c| c.snippet.is_none())
.collect::<Vec<_>>();
assert_eq_dbg(expected_completions, &completions);
}
fn check_snippet_completion(code: &str, expected_completions: &str) {
let (analysis, position) = single_file_with_position(code);
let completions = completions(&analysis.imp.db, position)
.unwrap()
.unwrap()
.into_iter()
.filter(|c| c.snippet.is_some())
.collect::<Vec<_>>();
assert_eq_dbg(expected_completions, &completions);
}
#[test]
fn test_completion_let_scope() {
check_scope_completion(
r"
fn quux(x: i32) {
let y = 92;
1 + <|>;
let z = ();
}
",
r#"[CompletionItem { label: "y", lookup: None, snippet: None },
CompletionItem { label: "x", lookup: None, snippet: None },
CompletionItem { label: "quux", lookup: None, snippet: None }]"#,
);
}
#[test]
fn test_completion_if_let_scope() {
check_scope_completion(
r"
fn quux() {
if let Some(x) = foo() {
let y = 92;
};
if let Some(a) = bar() {
let b = 62;
1 + <|>
}
}
",
r#"[CompletionItem { label: "b", lookup: None, snippet: None },
CompletionItem { label: "a", lookup: None, snippet: None },
CompletionItem { label: "quux", lookup: None, snippet: None }]"#,
);
}
#[test]
fn test_completion_for_scope() {
check_scope_completion(
r"
fn quux() {
for x in &[1, 2, 3] {
<|>
}
}
",
r#"[CompletionItem { label: "x", lookup: None, snippet: None },
CompletionItem { label: "quux", lookup: None, snippet: None }]"#,
);
}
#[test]
fn test_completion_mod_scope() {
check_scope_completion(
r"
struct Foo;
enum Baz {}
fn quux() {
<|>
}
",
r#"[CompletionItem { label: "quux", lookup: None, snippet: None },
CompletionItem { label: "Foo", lookup: None, snippet: None },
CompletionItem { label: "Baz", lookup: None, snippet: None }]"#,
);
}
#[test]
fn test_completion_mod_scope_no_self_use() {
check_scope_completion(
r"
use foo<|>;
",
r#"[]"#,
);
}
#[test]
fn test_completion_self_path() {
check_scope_completion(
r"
use self::m::<|>;
mod m {
struct Bar;
}
",
r#"[CompletionItem { label: "Bar", lookup: None, snippet: None }]"#,
);
}
#[test]
fn test_completion_mod_scope_nested() {
check_scope_completion(
r"
struct Foo;
mod m {
struct Bar;
fn quux() { <|> }
}
",
r#"[CompletionItem { label: "quux", lookup: None, snippet: None },
CompletionItem { label: "Bar", lookup: None, snippet: None }]"#,
);
}
#[test]
fn test_complete_type() {
check_scope_completion(
r"
struct Foo;
fn x() -> <|>
",
r#"[CompletionItem { label: "Foo", lookup: None, snippet: None },
CompletionItem { label: "x", lookup: None, snippet: None }]"#,
)
}
#[test]
fn test_complete_shadowing() {
check_scope_completion(
r"
fn foo() -> {
let bar = 92;
{
let bar = 62;
<|>
}
}
",
r#"[CompletionItem { label: "bar", lookup: None, snippet: None },
CompletionItem { label: "foo", lookup: None, snippet: None }]"#,
)
}
#[test]
fn test_complete_self() {
check_scope_completion(
r"
impl S { fn foo(&self) { <|> } }
",
r#"[CompletionItem { label: "self", lookup: None, snippet: None }]"#,
)
}
#[test]
fn test_completion_kewords() {
check_snippet_completion(r"
fn quux() {
<|>
}
", r#"[CompletionItem { label: "if", lookup: None, snippet: Some("if $0 {}") },
CompletionItem { label: "match", lookup: None, snippet: Some("match $0 {}") },
CompletionItem { label: "while", lookup: None, snippet: Some("while $0 {}") },
CompletionItem { label: "loop", lookup: None, snippet: Some("loop {$0}") },
CompletionItem { label: "return", lookup: None, snippet: Some("return") },
CompletionItem { label: "pd", lookup: None, snippet: Some("eprintln!(\"$0 = {:?}\", $0);") },
CompletionItem { label: "ppd", lookup: None, snippet: Some("eprintln!(\"$0 = {:#?}\", $0);") }]"#);
}
#[test]
fn test_completion_else() {
check_snippet_completion(r"
fn quux() {
if true {
()
} <|>
}
", r#"[CompletionItem { label: "if", lookup: None, snippet: Some("if $0 {}") },
CompletionItem { label: "match", lookup: None, snippet: Some("match $0 {}") },
CompletionItem { label: "while", lookup: None, snippet: Some("while $0 {}") },
CompletionItem { label: "loop", lookup: None, snippet: Some("loop {$0}") },
CompletionItem { label: "else", lookup: None, snippet: Some("else {$0}") },
CompletionItem { label: "else if", lookup: None, snippet: Some("else if $0 {}") },
CompletionItem { label: "return", lookup: None, snippet: Some("return") },
CompletionItem { label: "pd", lookup: None, snippet: Some("eprintln!(\"$0 = {:?}\", $0);") },
CompletionItem { label: "ppd", lookup: None, snippet: Some("eprintln!(\"$0 = {:#?}\", $0);") }]"#);
}
#[test]
fn test_completion_return_value() {
check_snippet_completion(r"
fn quux() -> i32 {
<|>
92
}
", r#"[CompletionItem { label: "if", lookup: None, snippet: Some("if $0 {}") },
CompletionItem { label: "match", lookup: None, snippet: Some("match $0 {}") },
CompletionItem { label: "while", lookup: None, snippet: Some("while $0 {}") },
CompletionItem { label: "loop", lookup: None, snippet: Some("loop {$0}") },
CompletionItem { label: "return", lookup: None, snippet: Some("return $0;") },
CompletionItem { label: "pd", lookup: None, snippet: Some("eprintln!(\"$0 = {:?}\", $0);") },
CompletionItem { label: "ppd", lookup: None, snippet: Some("eprintln!(\"$0 = {:#?}\", $0);") }]"#);
check_snippet_completion(r"
fn quux() {
<|>
92
}
", r#"[CompletionItem { label: "if", lookup: None, snippet: Some("if $0 {}") },
CompletionItem { label: "match", lookup: None, snippet: Some("match $0 {}") },
CompletionItem { label: "while", lookup: None, snippet: Some("while $0 {}") },
CompletionItem { label: "loop", lookup: None, snippet: Some("loop {$0}") },
CompletionItem { label: "return", lookup: None, snippet: Some("return;") },
CompletionItem { label: "pd", lookup: None, snippet: Some("eprintln!(\"$0 = {:?}\", $0);") },
CompletionItem { label: "ppd", lookup: None, snippet: Some("eprintln!(\"$0 = {:#?}\", $0);") }]"#);
}
#[test]
fn test_completion_return_no_stmt() {
check_snippet_completion(r"
fn quux() -> i32 {
match () {
() => <|>
}
}
", r#"[CompletionItem { label: "if", lookup: None, snippet: Some("if $0 {}") },
CompletionItem { label: "match", lookup: None, snippet: Some("match $0 {}") },
CompletionItem { label: "while", lookup: None, snippet: Some("while $0 {}") },
CompletionItem { label: "loop", lookup: None, snippet: Some("loop {$0}") },
CompletionItem { label: "return", lookup: None, snippet: Some("return $0") },
CompletionItem { label: "pd", lookup: None, snippet: Some("eprintln!(\"$0 = {:?}\", $0);") },
CompletionItem { label: "ppd", lookup: None, snippet: Some("eprintln!(\"$0 = {:#?}\", $0);") }]"#);
}
#[test]
fn test_continue_break_completion() {
check_snippet_completion(r"
fn quux() -> i32 {
loop { <|> }
}
", r#"[CompletionItem { label: "if", lookup: None, snippet: Some("if $0 {}") },
CompletionItem { label: "match", lookup: None, snippet: Some("match $0 {}") },
CompletionItem { label: "while", lookup: None, snippet: Some("while $0 {}") },
CompletionItem { label: "loop", lookup: None, snippet: Some("loop {$0}") },
CompletionItem { label: "continue", lookup: None, snippet: Some("continue") },
CompletionItem { label: "break", lookup: None, snippet: Some("break") },
CompletionItem { label: "return", lookup: None, snippet: Some("return $0") },
CompletionItem { label: "pd", lookup: None, snippet: Some("eprintln!(\"$0 = {:?}\", $0);") },
CompletionItem { label: "ppd", lookup: None, snippet: Some("eprintln!(\"$0 = {:#?}\", $0);") }]"#);
check_snippet_completion(r"
fn quux() -> i32 {
loop { || { <|> } }
}
", r#"[CompletionItem { label: "if", lookup: None, snippet: Some("if $0 {}") },
CompletionItem { label: "match", lookup: None, snippet: Some("match $0 {}") },
CompletionItem { label: "while", lookup: None, snippet: Some("while $0 {}") },
CompletionItem { label: "loop", lookup: None, snippet: Some("loop {$0}") },
CompletionItem { label: "return", lookup: None, snippet: Some("return $0") },
CompletionItem { label: "pd", lookup: None, snippet: Some("eprintln!(\"$0 = {:?}\", $0);") },
CompletionItem { label: "ppd", lookup: None, snippet: Some("eprintln!(\"$0 = {:#?}\", $0);") }]"#);
}
#[test]
fn test_param_completion_last_param() {
check_scope_completion(r"
fn foo(file_id: FileId) {}
fn bar(file_id: FileId) {}
fn baz(file<|>) {}
", r#"[CompletionItem { label: "file_id: FileId", lookup: Some("file_id"), snippet: None }]"#);
}
#[test]
fn test_param_completion_nth_param() {
check_scope_completion(r"
fn foo(file_id: FileId) {}
fn bar(file_id: FileId) {}
fn baz(file<|>, x: i32) {}
", r#"[CompletionItem { label: "file_id: FileId", lookup: Some("file_id"), snippet: None }]"#);
}
#[test]
fn test_param_completion_trait_param() {
check_scope_completion(r"
pub(crate) trait SourceRoot {
pub fn contains(&self, file_id: FileId) -> bool;
pub fn module_map(&self) -> &ModuleMap;
pub fn lines(&self, file_id: FileId) -> &LineIndex;
pub fn syntax(&self, file<|>)
}
", r#"[CompletionItem { label: "self", lookup: None, snippet: None },
CompletionItem { label: "SourceRoot", lookup: None, snippet: None },
CompletionItem { label: "file_id: FileId", lookup: Some("file_id"), snippet: None }]"#);
}
#[test]
fn test_item_snippets() {
// check_snippet_completion(r"
// <|>
// ",
// r##"[CompletionItem { label: "Test function", lookup: None, snippet: Some("#[test]\nfn test_${1:feature}() {\n$0\n}"##,
// );
check_snippet_completion(r"
#[cfg(test)]
mod tests {
<|>
}
",
r##"[CompletionItem { label: "Test function", lookup: Some("tfn"), snippet: Some("#[test]\nfn ${1:feature}() {\n$0\n}") },
CompletionItem { label: "pub(crate)", lookup: None, snippet: Some("pub(crate) $0") }]"##,
);
}
}