Added discovery of struct members inside constructors

crates/cairo-lang-language-server/src/lang/inspect/defs.rs

@@ -317,7 +317,9 @@ pub fn find_definition(
         }
     }
 
-    if let Some(member_id) = try_extract_member(db, identifier, lookup_items) {
+    if let Some(member_id) = try_extract_member(db, identifier, lookup_items)
+        .or_else(|| try_extract_member_from_constructor(db, identifier, lookup_items))
+    {
         return Some((ResolvedItem::Member(member_id), member_id.untyped_stable_ptr(db)));
     }
 
@@ -363,6 +365,46 @@ pub fn find_definition(
     }
 }
 
+/// Extracts [`MemberId`] if the [`ast::TerminalIdentifier`] is used as a struct member
+/// in [`ast::ExprStructCtorCall`].
+fn try_extract_member_from_constructor(
+    db: &AnalysisDatabase,
+    identifier: &ast::TerminalIdentifier,
+    lookup_items: &[LookupItemId],
+) -> Option<MemberId> {
+    let function_id = lookup_items.first()?.function_with_body()?;
+
+    let identifier_node = identifier.as_syntax_node();
+
+    let struct_member =
+        db.first_ancestor_of_kind(identifier_node.clone(), SyntaxKind::StructArgSingle)?;
+    let struct_member = ast::StructArgSingle::from_syntax_node(db, struct_member);
+
+    let ast::OptionStructArgExpr::StructArgExpr(struct_member_expr) = struct_member.arg_expr(db)
+    else {
+        return None;
+    };
+
+    let struct_member_expr_id =
+        db.lookup_expr_by_ptr(function_id, struct_member_expr.expr(db).stable_ptr()).ok()?;
+
+    let constructor = db.first_ancestor_of_kind(identifier_node, SyntaxKind::ExprStructCtorCall)?;
+    let constructor_expr = ast::ExprStructCtorCall::from_syntax_node(db, constructor);
+    let constructor_expr_id =
+        db.lookup_expr_by_ptr(function_id, constructor_expr.stable_ptr().into()).ok()?;
+
+    let Expr::StructCtor(constructor_expr_semantic) =
+        db.expr_semantic(function_id, constructor_expr_id)
+    else {
+        return None;
+    };
+
+    constructor_expr_semantic
+        .members
+        .iter()
+        .find_map(|(id, expr_id)| struct_member_expr_id.eq(expr_id).then_some(*id))
+}
+
 /// Extracts [`MemberId`] if the [`ast::TerminalIdentifier`] points to
 /// right-hand side of access member expression e.g., to `xyz` in `self.xyz`.
 fn try_extract_member(

crates/cairo-lang-language-server/tests/e2e/hover.rs

@@ -17,6 +17,7 @@ cairo_lang_test_utils::test_file_test!(
         partial: "partial.txt",
         starknet: "starknet.txt",
         literals: "literals.txt",
+        structs: "structs.txt"
     },
     test_hover
 );

crates/cairo-lang-language-server/tests/test_data/hover/basic.txt

@@ -232,11 +232,20 @@ Rectangle struct.
 // = source context
     let mut rect = Rectangle { wid<caret>th: 30, height: 50 };
 // = highlight
-No highlight information.
+    let mut rect = Rectangle { <sel>width</sel>: 30, height: 50 };
 // = popover
 ```cairo
-hello::Rectangle
+hello
 ```
+```cairo
+#[derive(Copy, Drop)]
+struct Rectangle {
+    width: u64,
+    height: u64,
+}
+```
+---
+Width of the rectangle.
 
 //! > hover #12
 // = source context

crates/cairo-lang-language-server/tests/test_data/hover/structs.txt

@@ -0,0 +1,119 @@
+//! > Hover
+
+//! > test_runner_name
+test_hover
+
+//! > cairo_project.toml
+[crate_roots]
+hello = "src"
+
+[config.global]
+edition = "2023_11"
+
+//! > cairo_code
+/// Docstring of Struct.
+struct Struct {
+    /// Docstring of member1.
+    member<caret>1: felt252,
+    member2: u256
+}
+
+mod happy_cases {
+    use super::Struct;
+
+    fn constructor() {
+        let _s = Struct {  member1<caret>: 0, member2: 0 };
+        let _s = Struct {  member1: 0, mem<caret>ber2: 0 };
+    }
+
+    fn member_access() {
+        let s = Struct {  member1: 0, member2: 0 };
+        let _ = s.member1<caret>;
+    }
+}
+
+mod unhappy_cases {
+    fn non_existent_struct {
+        let _ = NonExistentStruct { mem<caret>ber: 0 };
+    }
+}
+
+//! > hover #0
+// = source context
+    member<caret>1: felt252,
+// = highlight
+    <sel>member1</sel>: felt252,
+// = popover
+```cairo
+hello
+```
+```cairo
+struct Struct {
+    member1: felt252,
+    member2: u256,
+}
+```
+---
+Docstring of Struct.
+
+//! > hover #1
+// = source context
+        let _s = Struct {  member1<caret>: 0, member2: 0 };
+// = highlight
+        let _s = Struct {  <sel>member1</sel>: 0, member2: 0 };
+// = popover
+```cairo
+hello
+```
+```cairo
+struct Struct {
+    member1: felt252,
+    member2: u256,
+}
+```
+---
+Docstring of member1.
+
+//! > hover #2
+// = source context
+        let _s = Struct {  member1: 0, mem<caret>ber2: 0 };
+// = highlight
+        let _s = Struct {  member1: 0, <sel>member2</sel>: 0 };
+// = popover
+```cairo
+hello
+```
+```cairo
+struct Struct {
+    member1: felt252,
+    member2: u256,
+}
+```
+
+//! > hover #3
+// = source context
+        let _ = s.member1<caret>;
+// = highlight
+        let _ = s.<sel>member1</sel>;
+// = popover
+```cairo
+hello
+```
+```cairo
+struct Struct {
+    member1: felt252,
+    member2: u256,
+}
+```
+---
+Docstring of member1.
+
+//! > hover #4
+// = source context
+        let _ = NonExistentStruct { mem<caret>ber: 0 };
+// = highlight
+No highlight information.
+// = popover
+```cairo
+<missing>
+```