bendns' repos / rust-analyzer
Unnamed repository; edit this file 'description' to name the repository.
Diffstat (limited to 'crates/ide/src/signature_help.rs')
-rw-r--r--crates/ide/src/signature_help.rs89
1 files changed, 79 insertions, 10 deletions
diff --git a/crates/ide/src/signature_help.rs b/crates/ide/src/signature_help.rs
index 030790e470..06fdc641f8 100644
--- a/crates/ide/src/signature_help.rs
+++ b/crates/ide/src/signature_help.rs
@@ -4,11 +4,15 @@
use either::Either;
use hir::{HasAttrs, HirDisplay, Semantics};
use ide_db::{
- active_parameter::{callable_for_token, generics_for_token},
+ active_parameter::{callable_for_node, generics_for_token},
base_db::FilePosition,
};
use stdx::format_to;
-use syntax::{algo, AstNode, Direction, TextRange, TextSize};
+use syntax::{
+ algo,
+ ast::{self, HasArgList},
+ AstNode, Direction, SyntaxToken, TextRange, TextSize,
+};
use crate::RootDatabase;
@@ -65,8 +69,8 @@ pub(crate) fn signature_help(db: &RootDatabase, position: FilePosition) -> Optio
.and_then(|tok| algo::skip_trivia_token(tok, Direction::Prev))?;
let token = sema.descend_into_macros_single(token);
- if let Some((callable, active_parameter)) = callable_for_token(&sema, token.clone()) {
- return Some(signature_help_for_callable(db, callable, active_parameter));
+ if let Some(help) = signature_help_for_call(&sema, &token) {
+ return Some(help);
}
if let Some((generic_def, active_parameter)) = generics_for_token(&sema, token.clone()) {
@@ -76,14 +80,39 @@ pub(crate) fn signature_help(db: &RootDatabase, position: FilePosition) -> Optio
None
}
-fn signature_help_for_callable(
- db: &RootDatabase,
- callable: hir::Callable,
- active_parameter: Option<usize>,
-) -> SignatureHelp {
+fn signature_help_for_call(
+ sema: &Semantics<RootDatabase>,
+ token: &SyntaxToken,
+) -> Option<SignatureHelp> {
+ // Find the calling expression and its NameRef
+ let mut node = token.parent()?;
+ let calling_node = loop {
+ if let Some(callable) = ast::CallableExpr::cast(node.clone()) {
+ if callable
+ .arg_list()
+ .map_or(false, |it| it.syntax().text_range().contains(token.text_range().start()))
+ {
+ break callable;
+ }
+ }
+
+ // Stop at multi-line expressions, since the signature of the outer call is not very
+ // helpful inside them.
+ if let Some(expr) = ast::Expr::cast(node.clone()) {
+ if expr.syntax().text().contains_char('\n') {
+ return None;
+ }
+ }
+
+ node = node.parent()?;
+ };
+
+ let (callable, active_parameter) = callable_for_node(sema, &calling_node, token)?;
+
let mut res =
SignatureHelp { doc: None, signature: String::new(), parameters: vec![], active_parameter };
+ let db = sema.db;
match callable.kind() {
hir::CallableKind::Function(func) => {
res.doc = func.docs(db).map(|it| it.into());
@@ -134,7 +163,7 @@ fn signature_help_for_callable(
}
hir::CallableKind::TupleStruct(_) | hir::CallableKind::TupleEnumVariant(_) => {}
}
- res
+ Some(res)
}
fn signature_help_for_generics(
@@ -787,6 +816,46 @@ fn main() {
}
#[test]
+ fn test_multiline_argument() {
+ check(
+ r#"
+fn callee(a: u8, b: u8) {}
+fn main() {
+ callee(match 0 {
+ 0 => 1,$0
+ })
+}"#,
+ expect![[r#""#]],
+ );
+ check(
+ r#"
+fn callee(a: u8, b: u8) {}
+fn main() {
+ callee(match 0 {
+ 0 => 1,
+ },$0)
+}"#,
+ expect![[r#"
+ fn callee(a: u8, b: u8)
+ ----- ^^^^^
+ "#]],
+ );
+ check(
+ r#"
+fn callee(a: u8, b: u8) {}
+fn main() {
+ callee($0match 0 {
+ 0 => 1,
+ })
+}"#,
+ expect![[r#"
+ fn callee(a: u8, b: u8)
+ ^^^^^ -----
+ "#]],
+ );
+ }
+
+ #[test]
fn test_generics_simple() {
check(
r#"