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|
mod completion_item;
mod reference_completion;
use ra_editor::find_node_at_offset;
use ra_text_edit::AtomTextEdit;
use ra_syntax::{
algo::visit::{visitor_ctx, VisitorCtx},
ast,
AstNode,
SyntaxNodeRef,
};
use ra_db::SyntaxDatabase;
use rustc_hash::{FxHashMap};
use hir::source_binder;
use crate::{
db,
Cancelable, FilePosition,
completion::completion_item::{Completions, CompletionKind},
};
pub use crate::completion::completion_item::{CompletionItem, InsertText};
pub(crate) fn completions(
db: &db::RootDatabase,
position: FilePosition,
) -> Cancelable<Option<Completions>> {
let original_file = db.source_file(position.file_id);
// Insert a fake ident to get a valid parse tree
let file = {
let edit = AtomTextEdit::insert(position.offset, "intellijRulezz".to_string());
original_file.reparse(&edit)
};
let module = ctry!(source_binder::module_from_position(db, position)?);
let mut acc = Completions::default();
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 acc, 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(&mut acc, name_ref.syntax());
}
}
// 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(&mut acc, name.syntax());
}
}
if !has_completions {
return Ok(None);
}
Ok(Some(acc))
}
/// Complete repeated parametes, both name and type. For example, if all
/// functions in a file have a `spam: &mut Spam` parameter, a completion with
/// `spam: &mut Spam` insert text/label and `spam` lookup string will be
/// suggested.
fn param_completions(acc: &mut Completions, ctx: SyntaxNodeRef) {
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)| {
CompletionItem::new(label)
.lookup_by(lookup)
.kind(CompletionKind::Magic)
.add_to(acc)
});
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)]
fn check_completion(code: &str, expected_completions: &str, kind: CompletionKind) {
use crate::mock_analysis::{single_file_with_position, analysis_and_position};
let (analysis, position) = if code.contains("//-") {
analysis_and_position(code)
} else {
single_file_with_position(code)
};
let completions = completions(&analysis.imp.db, position).unwrap().unwrap();
completions.assert_match(expected_completions, kind);
}
#[cfg(test)]
mod tests {
use super::*;
fn check_magic_completion(code: &str, expected_completions: &str) {
check_completion(code, expected_completions, CompletionKind::Magic);
}
#[test]
fn test_param_completion_last_param() {
check_magic_completion(
r"
fn foo(file_id: FileId) {}
fn bar(file_id: FileId) {}
fn baz(file<|>) {}
",
r#"file_id "file_id: FileId""#,
);
}
#[test]
fn test_param_completion_nth_param() {
check_magic_completion(
r"
fn foo(file_id: FileId) {}
fn bar(file_id: FileId) {}
fn baz(file<|>, x: i32) {}
",
r#"file_id "file_id: FileId""#,
);
}
#[test]
fn test_param_completion_trait_param() {
check_magic_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#"file_id "file_id: FileId""#,
);
}
}
|
