From b6ea56ea091ad1dbd765831d8dfe79e4d3cdf004 Mon Sep 17 00:00:00 2001 From: Igor Aleksanov Date: Sat, 24 Oct 2020 11:07:10 +0300 Subject: Make call_info a part of ide_db --- crates/ide_db/src/call_info.rs | 756 +++++++++++++++++++++++++++++++++++++++++ 1 file changed, 756 insertions(+) create mode 100644 crates/ide_db/src/call_info.rs (limited to 'crates/ide_db/src/call_info.rs') diff --git a/crates/ide_db/src/call_info.rs b/crates/ide_db/src/call_info.rs new file mode 100644 index 000000000..83a602b9a --- /dev/null +++ b/crates/ide_db/src/call_info.rs @@ -0,0 +1,756 @@ +//! This crate provides primitives for tracking the information about a call site. +use base_db::FilePosition; +use either::Either; +use hir::{HasAttrs, HirDisplay, Semantics, Type}; +use stdx::format_to; +use syntax::{ + ast::{self, ArgListOwner}, + match_ast, AstNode, SyntaxNode, SyntaxToken, TextRange, TextSize, +}; +use test_utils::mark; + +use crate::RootDatabase; + +/// Contains information about a call site. Specifically the +/// `FunctionSignature`and current parameter. +#[derive(Debug)] +pub struct CallInfo { + pub doc: Option, + pub signature: String, + pub active_parameter: Option, + parameters: Vec, +} + +impl CallInfo { + pub fn parameter_labels(&self) -> impl Iterator + '_ { + self.parameters.iter().map(move |&it| &self.signature[it]) + } + pub fn parameter_ranges(&self) -> &[TextRange] { + &self.parameters + } + fn push_param(&mut self, param: &str) { + if !self.signature.ends_with('(') { + self.signature.push_str(", "); + } + let start = TextSize::of(&self.signature); + self.signature.push_str(param); + let end = TextSize::of(&self.signature); + self.parameters.push(TextRange::new(start, end)) + } +} + +/// Computes parameter information for the given call expression. +pub fn call_info(db: &RootDatabase, position: FilePosition) -> Option { + let sema = Semantics::new(db); + let file = sema.parse(position.file_id); + let file = file.syntax(); + let token = file.token_at_offset(position.offset).next()?; + let token = sema.descend_into_macros(token); + + let (callable, active_parameter) = call_info_impl(&sema, token)?; + + let mut res = + CallInfo { doc: None, signature: String::new(), parameters: vec![], active_parameter }; + + match callable.kind() { + hir::CallableKind::Function(func) => { + res.doc = func.docs(db).map(|it| it.as_str().to_string()); + format_to!(res.signature, "fn {}", func.name(db)); + } + hir::CallableKind::TupleStruct(strukt) => { + res.doc = strukt.docs(db).map(|it| it.as_str().to_string()); + format_to!(res.signature, "struct {}", strukt.name(db)); + } + hir::CallableKind::TupleEnumVariant(variant) => { + res.doc = variant.docs(db).map(|it| it.as_str().to_string()); + format_to!( + res.signature, + "enum {}::{}", + variant.parent_enum(db).name(db), + variant.name(db) + ); + } + hir::CallableKind::Closure => (), + } + + res.signature.push('('); + { + if let Some(self_param) = callable.receiver_param(db) { + format_to!(res.signature, "{}", self_param) + } + let mut buf = String::new(); + for (pat, ty) in callable.params(db) { + buf.clear(); + if let Some(pat) = pat { + match pat { + Either::Left(_self) => format_to!(buf, "self: "), + Either::Right(pat) => format_to!(buf, "{}: ", pat), + } + } + format_to!(buf, "{}", ty.display(db)); + res.push_param(&buf); + } + } + res.signature.push(')'); + + match callable.kind() { + hir::CallableKind::Function(_) | hir::CallableKind::Closure => { + let ret_type = callable.return_type(); + if !ret_type.is_unit() { + format_to!(res.signature, " -> {}", ret_type.display(db)); + } + } + hir::CallableKind::TupleStruct(_) | hir::CallableKind::TupleEnumVariant(_) => {} + } + Some(res) +} + +fn call_info_impl( + sema: &Semantics, + token: SyntaxToken, +) -> Option<(hir::Callable, Option)> { + // Find the calling expression and it's NameRef + let calling_node = FnCallNode::with_node(&token.parent())?; + + let callable = match &calling_node { + FnCallNode::CallExpr(call) => sema.type_of_expr(&call.expr()?)?.as_callable(sema.db)?, + FnCallNode::MethodCallExpr(call) => sema.resolve_method_call_as_callable(call)?, + }; + let active_param = if let Some(arg_list) = calling_node.arg_list() { + // Number of arguments specified at the call site + let num_args_at_callsite = arg_list.args().count(); + + let arg_list_range = arg_list.syntax().text_range(); + if !arg_list_range.contains_inclusive(token.text_range().start()) { + mark::hit!(call_info_bad_offset); + return None; + } + let param = std::cmp::min( + num_args_at_callsite, + arg_list + .args() + .take_while(|arg| arg.syntax().text_range().end() <= token.text_range().start()) + .count(), + ); + + Some(param) + } else { + None + }; + Some((callable, active_param)) +} + +#[derive(Debug)] +pub struct ActiveParameter { + pub ty: Type, + pub name: String, +} + +impl ActiveParameter { + pub fn at(db: &RootDatabase, position: FilePosition) -> Option { + let sema = Semantics::new(db); + let file = sema.parse(position.file_id); + let file = file.syntax(); + let token = file.token_at_offset(position.offset).next()?; + let token = sema.descend_into_macros(token); + Self::at_token(&sema, token) + } + + pub fn at_token(sema: &Semantics, token: SyntaxToken) -> Option { + let (signature, active_parameter) = call_info_impl(&sema, token)?; + + let idx = active_parameter?; + let mut params = signature.params(sema.db); + if !(idx < params.len()) { + mark::hit!(too_many_arguments); + return None; + } + let (pat, ty) = params.swap_remove(idx); + let name = pat?.to_string(); + Some(ActiveParameter { ty, name }) + } +} + +#[derive(Debug)] +pub enum FnCallNode { + CallExpr(ast::CallExpr), + MethodCallExpr(ast::MethodCallExpr), +} + +impl FnCallNode { + fn with_node(syntax: &SyntaxNode) -> Option { + syntax.ancestors().find_map(|node| { + match_ast! { + match node { + ast::CallExpr(it) => Some(FnCallNode::CallExpr(it)), + ast::MethodCallExpr(it) => { + let arg_list = it.arg_list()?; + if !arg_list.syntax().text_range().contains_range(syntax.text_range()) { + return None; + } + Some(FnCallNode::MethodCallExpr(it)) + }, + _ => None, + } + } + }) + } + + pub fn with_node_exact(node: &SyntaxNode) -> Option { + match_ast! { + match node { + ast::CallExpr(it) => Some(FnCallNode::CallExpr(it)), + ast::MethodCallExpr(it) => Some(FnCallNode::MethodCallExpr(it)), + _ => None, + } + } + } + + pub fn name_ref(&self) -> Option { + match self { + FnCallNode::CallExpr(call_expr) => Some(match call_expr.expr()? { + ast::Expr::PathExpr(path_expr) => path_expr.path()?.segment()?.name_ref()?, + _ => return None, + }), + + FnCallNode::MethodCallExpr(call_expr) => { + call_expr.syntax().children().filter_map(ast::NameRef::cast).next() + } + } + } + + fn arg_list(&self) -> Option { + match self { + FnCallNode::CallExpr(expr) => expr.arg_list(), + FnCallNode::MethodCallExpr(expr) => expr.arg_list(), + } + } +} + +#[cfg(test)] +mod tests { + use crate::RootDatabase; + use base_db::{fixture::ChangeFixture, FilePosition}; + use expect_test::{expect, Expect}; + use test_utils::{mark, RangeOrOffset}; + + /// Creates analysis from a multi-file fixture, returns positions marked with <|>. + pub(crate) fn position(ra_fixture: &str) -> (RootDatabase, FilePosition) { + let change_fixture = ChangeFixture::parse(ra_fixture); + let mut database = RootDatabase::default(); + database.apply_change(change_fixture.change); + let (file_id, range_or_offset) = + change_fixture.file_position.expect("expected a marker (<|>)"); + let offset = match range_or_offset { + RangeOrOffset::Range(_) => panic!(), + RangeOrOffset::Offset(it) => it, + }; + (database, FilePosition { file_id, offset }) + } + + fn check(ra_fixture: &str, expect: Expect) { + let (db, position) = position(ra_fixture); + let call_info = crate::call_info::call_info(&db, position); + let actual = match call_info { + Some(call_info) => { + let docs = match &call_info.doc { + None => "".to_string(), + Some(docs) => format!("{}\n------\n", docs.as_str()), + }; + let params = call_info + .parameter_labels() + .enumerate() + .map(|(i, param)| { + if Some(i) == call_info.active_parameter { + format!("<{}>", param) + } else { + param.to_string() + } + }) + .collect::>() + .join(", "); + format!("{}{}\n({})\n", docs, call_info.signature, params) + } + None => String::new(), + }; + expect.assert_eq(&actual); + } + + #[test] + fn test_fn_signature_two_args() { + check( + r#" +fn foo(x: u32, y: u32) -> u32 {x + y} +fn bar() { foo(<|>3, ); } +"#, + expect![[r#" + fn foo(x: u32, y: u32) -> u32 + (, y: u32) + "#]], + ); + check( + r#" +fn foo(x: u32, y: u32) -> u32 {x + y} +fn bar() { foo(3<|>, ); } +"#, + expect![[r#" + fn foo(x: u32, y: u32) -> u32 + (, y: u32) + "#]], + ); + check( + r#" +fn foo(x: u32, y: u32) -> u32 {x + y} +fn bar() { foo(3,<|> ); } +"#, + expect![[r#" + fn foo(x: u32, y: u32) -> u32 + (x: u32, ) + "#]], + ); + check( + r#" +fn foo(x: u32, y: u32) -> u32 {x + y} +fn bar() { foo(3, <|>); } +"#, + expect![[r#" + fn foo(x: u32, y: u32) -> u32 + (x: u32, ) + "#]], + ); + } + + #[test] + fn test_fn_signature_two_args_empty() { + check( + r#" +fn foo(x: u32, y: u32) -> u32 {x + y} +fn bar() { foo(<|>); } +"#, + expect![[r#" + fn foo(x: u32, y: u32) -> u32 + (, y: u32) + "#]], + ); + } + + #[test] + fn test_fn_signature_two_args_first_generics() { + check( + r#" +fn foo(x: T, y: U) -> u32 + where T: Copy + Display, U: Debug +{ x + y } + +fn bar() { foo(<|>3, ); } +"#, + expect![[r#" + fn foo(x: i32, y: {unknown}) -> u32 + (, y: {unknown}) + "#]], + ); + } + + #[test] + fn test_fn_signature_no_params() { + check( + r#" +fn foo() -> T where T: Copy + Display {} +fn bar() { foo(<|>); } +"#, + expect![[r#" + fn foo() -> {unknown} + () + "#]], + ); + } + + #[test] + fn test_fn_signature_for_impl() { + check( + r#" +struct F; +impl F { pub fn new() { } } +fn bar() { + let _ : F = F::new(<|>); +} +"#, + expect![[r#" + fn new() + () + "#]], + ); + } + + #[test] + fn test_fn_signature_for_method_self() { + check( + r#" +struct S; +impl S { pub fn do_it(&self) {} } + +fn bar() { + let s: S = S; + s.do_it(<|>); +} +"#, + expect![[r#" + fn do_it(&self) + () + "#]], + ); + } + + #[test] + fn test_fn_signature_for_method_with_arg() { + check( + r#" +struct S; +impl S { + fn foo(&self, x: i32) {} +} + +fn main() { S.foo(<|>); } +"#, + expect![[r#" + fn foo(&self, x: i32) + () + "#]], + ); + } + + #[test] + fn test_fn_signature_for_method_with_arg_as_assoc_fn() { + check( + r#" +struct S; +impl S { + fn foo(&self, x: i32) {} +} + +fn main() { S::foo(<|>); } +"#, + expect![[r#" + fn foo(self: &S, x: i32) + (, x: i32) + "#]], + ); + } + + #[test] + fn test_fn_signature_with_docs_simple() { + check( + r#" +/// test +// non-doc-comment +fn foo(j: u32) -> u32 { + j +} + +fn bar() { + let _ = foo(<|>); +} +"#, + expect![[r#" + test + ------ + fn foo(j: u32) -> u32 + () + "#]], + ); + } + + #[test] + fn test_fn_signature_with_docs() { + check( + r#" +/// Adds one to the number given. +/// +/// # Examples +/// +/// ``` +/// let five = 5; +/// +/// assert_eq!(6, my_crate::add_one(5)); +/// ``` +pub fn add_one(x: i32) -> i32 { + x + 1 +} + +pub fn do() { + add_one(<|> +}"#, + expect![[r##" + Adds one to the number given. + + # Examples + + ``` + let five = 5; + + assert_eq!(6, my_crate::add_one(5)); + ``` + ------ + fn add_one(x: i32) -> i32 + () + "##]], + ); + } + + #[test] + fn test_fn_signature_with_docs_impl() { + check( + r#" +struct addr; +impl addr { + /// Adds one to the number given. + /// + /// # Examples + /// + /// ``` + /// let five = 5; + /// + /// assert_eq!(6, my_crate::add_one(5)); + /// ``` + pub fn add_one(x: i32) -> i32 { + x + 1 + } +} + +pub fn do_it() { + addr {}; + addr::add_one(<|>); +} +"#, + expect![[r##" + Adds one to the number given. + + # Examples + + ``` + let five = 5; + + assert_eq!(6, my_crate::add_one(5)); + ``` + ------ + fn add_one(x: i32) -> i32 + () + "##]], + ); + } + + #[test] + fn test_fn_signature_with_docs_from_actix() { + check( + r#" +struct WriteHandler; + +impl WriteHandler { + /// Method is called when writer emits error. + /// + /// If this method returns `ErrorAction::Continue` writer processing + /// continues otherwise stream processing stops. + fn error(&mut self, err: E, ctx: &mut Self::Context) -> Running { + Running::Stop + } + + /// Method is called when writer finishes. + /// + /// By default this method stops actor's `Context`. + fn finished(&mut self, ctx: &mut Self::Context) { + ctx.stop() + } +} + +pub fn foo(mut r: WriteHandler<()>) { + r.finished(<|>); +} +"#, + expect![[r#" + Method is called when writer finishes. + + By default this method stops actor's `Context`. + ------ + fn finished(&mut self, ctx: &mut {unknown}) + () + "#]], + ); + } + + #[test] + fn call_info_bad_offset() { + mark::check!(call_info_bad_offset); + check( + r#" +fn foo(x: u32, y: u32) -> u32 {x + y} +fn bar() { foo <|> (3, ); } +"#, + expect![[""]], + ); + } + + #[test] + fn test_nested_method_in_lambda() { + check( + r#" +struct Foo; +impl Foo { fn bar(&self, _: u32) { } } + +fn bar(_: u32) { } + +fn main() { + let foo = Foo; + std::thread::spawn(move || foo.bar(<|>)); +} +"#, + expect![[r#" + fn bar(&self, _: u32) + (<_: u32>) + "#]], + ); + } + + #[test] + fn works_for_tuple_structs() { + check( + r#" +/// A cool tuple struct +struct S(u32, i32); +fn main() { + let s = S(0, <|>); +} +"#, + expect![[r#" + A cool tuple struct + ------ + struct S(u32, i32) + (u32, ) + "#]], + ); + } + + #[test] + fn generic_struct() { + check( + r#" +struct S(T); +fn main() { + let s = S(<|>); +} +"#, + expect![[r#" + struct S({unknown}) + (<{unknown}>) + "#]], + ); + } + + #[test] + fn works_for_enum_variants() { + check( + r#" +enum E { + /// A Variant + A(i32), + /// Another + B, + /// And C + C { a: i32, b: i32 } +} + +fn main() { + let a = E::A(<|>); +} +"#, + expect![[r#" + A Variant + ------ + enum E::A(i32) + () + "#]], + ); + } + + #[test] + fn cant_call_struct_record() { + check( + r#" +struct S { x: u32, y: i32 } +fn main() { + let s = S(<|>); +} +"#, + expect![[""]], + ); + } + + #[test] + fn cant_call_enum_record() { + check( + r#" +enum E { + /// A Variant + A(i32), + /// Another + B, + /// And C + C { a: i32, b: i32 } +} + +fn main() { + let a = E::C(<|>); +} +"#, + expect![[""]], + ); + } + + #[test] + fn fn_signature_for_call_in_macro() { + check( + r#" +macro_rules! id { ($($tt:tt)*) => { $($tt)* } } +fn foo() { } +id! { + fn bar() { foo(<|>); } +} +"#, + expect![[r#" + fn foo() + () + "#]], + ); + } + + #[test] + fn call_info_for_lambdas() { + check( + r#" +struct S; +fn foo(s: S) -> i32 { 92 } +fn main() { + (|s| foo(s))(<|>) +} + "#, + expect![[r#" + (S) -> i32 + () + "#]], + ) + } + + #[test] + fn call_info_for_fn_ptr() { + check( + r#" +fn main(f: fn(i32, f64) -> char) { + f(0, <|>) +} + "#, + expect![[r#" + (i32, f64) -> char + (i32, ) + "#]], + ) + } +} -- cgit v1.2.3