From 3db64a400c78bbd2708e67ddc07df1001fff3f29 Mon Sep 17 00:00:00 2001 From: Aleksey Kladov Date: Wed, 17 Feb 2021 17:53:31 +0300 Subject: rename completion -> ide_completion We don't have completion-related PRs in flight, so lets do it --- crates/ide_completion/src/lib.rs | 275 +++++++++++++++++++++++++++++++++++++++ 1 file changed, 275 insertions(+) create mode 100644 crates/ide_completion/src/lib.rs (limited to 'crates/ide_completion/src/lib.rs') diff --git a/crates/ide_completion/src/lib.rs b/crates/ide_completion/src/lib.rs new file mode 100644 index 000000000..db8bfbbc3 --- /dev/null +++ b/crates/ide_completion/src/lib.rs @@ -0,0 +1,275 @@ +//! `completions` crate provides utilities for generating completions of user input. + +mod config; +mod item; +mod context; +mod patterns; +mod generated_lint_completions; +#[cfg(test)] +mod test_utils; +mod render; + +mod completions; + +use completions::flyimport::position_for_import; +use ide_db::{ + base_db::FilePosition, helpers::insert_use::ImportScope, imports_locator, RootDatabase, +}; +use text_edit::TextEdit; + +use crate::{completions::Completions, context::CompletionContext, item::CompletionKind}; + +pub use crate::{ + config::CompletionConfig, + item::{CompletionItem, CompletionItemKind, CompletionScore, ImportEdit, InsertTextFormat}, +}; + +//FIXME: split the following feature into fine-grained features. + +// Feature: Magic Completions +// +// In addition to usual reference completion, rust-analyzer provides some ✨magic✨ +// completions as well: +// +// Keywords like `if`, `else` `while`, `loop` are completed with braces, and cursor +// is placed at the appropriate position. Even though `if` is easy to type, you +// still want to complete it, to get ` { }` for free! `return` is inserted with a +// space or `;` depending on the return type of the function. +// +// When completing a function call, `()` are automatically inserted. If a function +// takes arguments, the cursor is positioned inside the parenthesis. +// +// There are postfix completions, which can be triggered by typing something like +// `foo().if`. The word after `.` determines postfix completion. Possible variants are: +// +// - `expr.if` -> `if expr {}` or `if let ... {}` for `Option` or `Result` +// - `expr.match` -> `match expr {}` +// - `expr.while` -> `while expr {}` or `while let ... {}` for `Option` or `Result` +// - `expr.ref` -> `&expr` +// - `expr.refm` -> `&mut expr` +// - `expr.let` -> `let $0 = expr;` +// - `expr.letm` -> `let mut $0 = expr;` +// - `expr.not` -> `!expr` +// - `expr.dbg` -> `dbg!(expr)` +// - `expr.dbgr` -> `dbg!(&expr)` +// - `expr.call` -> `(expr)` +// +// There also snippet completions: +// +// .Expressions +// - `pd` -> `eprintln!(" = {:?}", );` +// - `ppd` -> `eprintln!(" = {:#?}", );` +// +// .Items +// - `tfn` -> `#[test] fn feature(){}` +// - `tmod` -> +// ```rust +// #[cfg(test)] +// mod tests { +// use super::*; +// +// #[test] +// fn test_name() {} +// } +// ``` +// +// And the auto import completions, enabled with the `rust-analyzer.completion.autoimport.enable` setting and the corresponding LSP client capabilities. +// Those are the additional completion options with automatic `use` import and options from all project importable items, +// fuzzy matched agains the completion imput. + +/// Main entry point for completion. We run completion as a two-phase process. +/// +/// First, we look at the position and collect a so-called `CompletionContext. +/// This is a somewhat messy process, because, during completion, syntax tree is +/// incomplete and can look really weird. +/// +/// Once the context is collected, we run a series of completion routines which +/// look at the context and produce completion items. One subtlety about this +/// phase is that completion engine should not filter by the substring which is +/// already present, it should give all possible variants for the identifier at +/// the caret. In other words, for +/// +/// ```no_run +/// fn f() { +/// let foo = 92; +/// let _ = bar$0 +/// } +/// ``` +/// +/// `foo` *should* be present among the completion variants. Filtering by +/// identifier prefix/fuzzy match should be done higher in the stack, together +/// with ordering of completions (currently this is done by the client). +pub fn completions( + db: &RootDatabase, + config: &CompletionConfig, + position: FilePosition, +) -> Option { + let ctx = CompletionContext::new(db, position, config)?; + + if ctx.no_completion_required() { + // No work required here. + return None; + } + + let mut acc = Completions::default(); + completions::attribute::complete_attribute(&mut acc, &ctx); + completions::fn_param::complete_fn_param(&mut acc, &ctx); + completions::keyword::complete_expr_keyword(&mut acc, &ctx); + completions::keyword::complete_use_tree_keyword(&mut acc, &ctx); + completions::snippet::complete_expr_snippet(&mut acc, &ctx); + completions::snippet::complete_item_snippet(&mut acc, &ctx); + completions::qualified_path::complete_qualified_path(&mut acc, &ctx); + completions::unqualified_path::complete_unqualified_path(&mut acc, &ctx); + completions::dot::complete_dot(&mut acc, &ctx); + completions::record::complete_record(&mut acc, &ctx); + completions::pattern::complete_pattern(&mut acc, &ctx); + completions::postfix::complete_postfix(&mut acc, &ctx); + completions::macro_in_item_position::complete_macro_in_item_position(&mut acc, &ctx); + completions::trait_impl::complete_trait_impl(&mut acc, &ctx); + completions::mod_::complete_mod(&mut acc, &ctx); + completions::flyimport::import_on_the_fly(&mut acc, &ctx); + + Some(acc) +} + +/// Resolves additional completion data at the position given. +pub fn resolve_completion_edits( + db: &RootDatabase, + config: &CompletionConfig, + position: FilePosition, + full_import_path: &str, + imported_name: String, + import_for_trait_assoc_item: bool, +) -> Option> { + let ctx = CompletionContext::new(db, position, config)?; + let position_for_import = position_for_import(&ctx, None)?; + let import_scope = ImportScope::find_insert_use_container(position_for_import, &ctx.sema)?; + + let current_module = ctx.sema.scope(position_for_import).module()?; + let current_crate = current_module.krate(); + + let import_path = imports_locator::find_exact_imports(&ctx.sema, current_crate, imported_name) + .filter_map(|candidate| { + let item: hir::ItemInNs = candidate.either(Into::into, Into::into); + current_module.find_use_path(db, item) + }) + .find(|mod_path| mod_path.to_string() == full_import_path)?; + + ImportEdit { import_path, import_scope, import_for_trait_assoc_item } + .to_text_edit(config.insert_use.merge) + .map(|edit| vec![edit]) +} + +#[cfg(test)] +mod tests { + use crate::test_utils::{self, TEST_CONFIG}; + + struct DetailAndDocumentation<'a> { + detail: &'a str, + documentation: &'a str, + } + + fn check_detail_and_documentation(ra_fixture: &str, expected: DetailAndDocumentation) { + let (db, position) = test_utils::position(ra_fixture); + let config = TEST_CONFIG; + let completions: Vec<_> = crate::completions(&db, &config, position).unwrap().into(); + for item in completions { + if item.detail() == Some(expected.detail) { + let opt = item.documentation(); + let doc = opt.as_ref().map(|it| it.as_str()); + assert_eq!(doc, Some(expected.documentation)); + return; + } + } + panic!("completion detail not found: {}", expected.detail) + } + + fn check_no_completion(ra_fixture: &str) { + let (db, position) = test_utils::position(ra_fixture); + let config = TEST_CONFIG; + + let completions: Option> = crate::completions(&db, &config, position) + .and_then(|completions| { + let completions: Vec<_> = completions.into(); + if completions.is_empty() { + None + } else { + Some(completions) + } + }) + .map(|completions| { + completions.into_iter().map(|completion| format!("{:?}", completion)).collect() + }); + + // `assert_eq` instead of `assert!(completions.is_none())` to get the list of completions if test will panic. + assert_eq!(completions, None, "Completions were generated, but weren't expected"); + } + + #[test] + fn test_completion_detail_from_macro_generated_struct_fn_doc_attr() { + check_detail_and_documentation( + r#" +macro_rules! bar { + () => { + struct Bar; + impl Bar { + #[doc = "Do the foo"] + fn foo(&self) {} + } + } +} + +bar!(); + +fn foo() { + let bar = Bar; + bar.fo$0; +} +"#, + DetailAndDocumentation { detail: "-> ()", documentation: "Do the foo" }, + ); + } + + #[test] + fn test_completion_detail_from_macro_generated_struct_fn_doc_comment() { + check_detail_and_documentation( + r#" +macro_rules! bar { + () => { + struct Bar; + impl Bar { + /// Do the foo + fn foo(&self) {} + } + } +} + +bar!(); + +fn foo() { + let bar = Bar; + bar.fo$0; +} +"#, + DetailAndDocumentation { detail: "-> ()", documentation: " Do the foo" }, + ); + } + + #[test] + fn test_no_completions_required() { + // There must be no hint for 'in' keyword. + check_no_completion(r#"fn foo() { for i i$0 }"#); + // After 'in' keyword hints may be spawned. + check_detail_and_documentation( + r#" +/// Do the foo +fn foo() -> &'static str { "foo" } + +fn bar() { + for c in fo$0 +} +"#, + DetailAndDocumentation { detail: "-> &str", documentation: "Do the foo" }, + ); + } +} -- cgit v1.2.3