Fix active parameter analysis once more

Author: Veykril

crates/ide-db/src/active_parameter.rs

@@ -2,10 +2,10 @@
 
 use either::Either;
 use hir::{Semantics, Type};
+use parser::T;
 use syntax::{
-    algo::non_trivia_sibling,
     ast::{self, HasArgList, HasName},
-    AstNode, Direction, SyntaxToken, TextRange,
+    AstNode, NodeOrToken, SyntaxToken,
 };
 
 use crate::RootDatabase;
@@ -59,32 +59,23 @@ pub fn callable_for_node(
     calling_node: &ast::CallableExpr,
     token: &SyntaxToken,
 ) -> Option<(hir::Callable, Option<usize>)> {
-    let callable = match &calling_node {
+    let callable = match calling_node {
         ast::CallableExpr::Call(call) => {
             let expr = call.expr()?;
             sema.type_of_expr(&expr)?.adjusted().as_callable(sema.db)
         }
         ast::CallableExpr::MethodCall(call) => sema.resolve_method_call_as_callable(call),
     }?;
     let active_param = if let Some(arg_list) = calling_node.arg_list() {
-        let account_for_ws = |arg: &ast::Expr| {
-            let node = arg.syntax().clone();
-            let left = non_trivia_sibling(node.clone().into(), Direction::Prev)
-                .and_then(|it| it.into_token())?
-                .text_range();
-            let right = non_trivia_sibling(node.into(), Direction::Next)
-                .and_then(|it| it.into_token())?
-                .text_range();
-            Some(TextRange::new(left.end(), right.start()))
-        };
-        arg_list
-            .args()
-            .position(|arg| {
-                account_for_ws(&arg)
-                    .unwrap_or(arg.syntax().text_range())
-                    .contains(token.text_range().start())
-            })
-            .or(Some(0))
+        Some(
+            arg_list
+                .syntax()
+                .children_with_tokens()
+                .filter_map(NodeOrToken::into_token)
+                .filter(|t| t.kind() == T![,])
+                .take_while(|t| t.text_range().start() <= token.text_range().start())
+                .count(),
+        )
     } else {
         None
     };

crates/ide/src/signature_help.rs

@@ -105,10 +105,10 @@ pub(crate) fn signature_help(db: &RootDatabase, position: FilePosition) -> Optio
         // 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')
-                && expr.syntax().kind() != SyntaxKind::RECORD_EXPR
+            if !matches!(expr, ast::Expr::RecordExpr(..))
+                && expr.syntax().text().contains_char('\n')
             {
-                return None;
+                break;
             }
         }
     }
@@ -122,18 +122,16 @@ fn signature_help_for_call(
     token: SyntaxToken,
 ) -> Option<SignatureHelp> {
     // Find the calling expression and its NameRef
-    let mut node = arg_list.syntax().parent()?;
+    let mut nodes = arg_list.syntax().ancestors().skip(1);
     let calling_node = loop {
-        if let Some(callable) = ast::CallableExpr::cast(node.clone()) {
-            if callable
+        if let Some(callable) = ast::CallableExpr::cast(nodes.next()?) {
+            let inside_callable = callable
                 .arg_list()
-                .map_or(false, |it| it.syntax().text_range().contains(token.text_range().start()))
-            {
+                .map_or(false, |it| it.syntax().text_range().contains(token.text_range().start()));
+            if inside_callable {
                 break callable;
             }
         }
-
-        node = node.parent()?;
     };
 
     let (callable, active_parameter) = callable_for_node(sema, &calling_node, &token)?;
@@ -1594,4 +1592,27 @@ impl S {
             "#]],
         );
     }
+
+    #[test]
+    fn test_enum_in_nested_method_in_lambda() {
+        check(
+            r#"
+enum A {
+    A,
+    B
+}
+
+fn bar(_: A) { }
+
+fn main() {
+    let foo = Foo;
+    std::thread::spawn(move || { bar(A:$0) } );
+}
+"#,
+            expect![[r#"
+                fn bar(_: A)
+                       ^^^^
+            "#]],
+        );
+    }
 }