feat: improve function hover text

src/eval/env/test.rs

@@ -244,7 +244,10 @@ fn function_definition_hover() {
         .pos_value(&Position::new(14, 9))
         .expect("obj should be some");
 
-    assert_eq!(value.obj, Object::Function(2, Box::new(Object::Unknown)));
+    assert_eq!(
+        value.obj,
+        Object::Function(vec!["x".into(), "y".into()], Box::new(Object::Unknown))
+    );
     assert_eq!(
         value.ident_rng,
         Range::new(Position::new(14, 4), Position::new(14, 13))

src/eval/mod.rs

@@ -288,6 +288,7 @@ impl<'source> Eval {
                 Ok(body) => {
                     let child_env = Env::new_child(self.env.clone(), body);
 
+                    let mut param_names = Vec::new();
                     for param in params {
                         match param {
                             Ok(Expression::Identifier(ident_expr)) => {
@@ -299,14 +300,15 @@ impl<'source> Eval {
                                     Arc::clone(&ident_expr.name),
                                 );
                                 child_env.insert_store(value);
+                                param_names.push(Arc::clone(&ident_expr.name));
                             }
                             Ok(_) => unreachable!(),
                             Err(err) => diags.push(err.clone().into()),
                         }
                     }
 
                     let (body_obj, body_diags) = Self::eval_block_stmt(body, child_env);
-                    obj = Object::Function(params.len(), Box::new(body_obj));
+                    obj = Object::Function(param_names, Box::new(body_obj));
                     diags.extend(body_diags);
                 }
                 Err(err) => diags.push(err.clone().into()),
@@ -331,8 +333,8 @@ impl<'source> Eval {
         let arg_count;
         let ret_type;
         match func_obj {
-            Object::Function(count, r_type) => {
-                arg_count = count;
+            Object::Function(args, r_type) => {
+                arg_count = args.len();
                 ret_type = *r_type;
             }
             Object::Builtin(func) => {

src/eval/object.rs

@@ -1,3 +1,5 @@
+use std::sync::Arc;
+
 use tower_lsp::lsp_types::{CompletionItem, CompletionItemKind};
 
 use crate::ast::Call;
@@ -10,7 +12,7 @@ pub enum Object {
     Int,
     Bool,
     String,
-    Function(usize, Box<Object>),
+    Function(Vec<Arc<str>>, Box<Object>),
     Builtin(Builtin),
     Array,
     Hash,
@@ -35,8 +37,7 @@ impl Object {
 
     pub fn hover_content(&self) -> String {
         match self {
-            Object::Function(arg_count, ret_type) => {
-                let args: Vec<String> = (0..*arg_count).map(|i| format!("arg{i}")).collect();
+            Object::Function(args, ret_type) => {
                 format!("fn({}) -> {}", args.join(", "), ret_type.typename())
             }
             Object::Builtin(func) => func.hover_content(),

src/eval/snapshots/monkey_language_server__eval__test__basic_func_1.snap

@@ -5,7 +5,7 @@ expression: "format!(\"{:#?}\\n\\n========================\\n\\n{:#?}\", env, di
 ---
 Environment {
     store: [
-        Value("foo", Function(0, Int), (0,4)->(0,7), (0,0)->(0,29)),
+        Value("foo", Function([], Int), (0,4)->(0,7), (0,0)->(0,29)),
     ],
     refs: [
         Pos("foo", "(0,4)->(0,7)"),

src/eval/snapshots/monkey_language_server__eval__test__basic_func_2.snap

@@ -5,7 +5,7 @@ expression: "format!(\"{:#?}\\n\\n========================\\n\\n{:#?}\", env, di
 ---
 Environment {
     store: [
-        Value("add", Function(2, Unknown), (0,4)->(0,7), (0,0)->(0,36)),
+        Value("add", Function(["x", "y"], Unknown), (0,4)->(0,7), (0,0)->(0,36)),
     ],
     refs: [
         Pos("add", "(0,4)->(0,7)"),

src/eval/snapshots/monkey_language_server__eval__test__basic_func_call.snap

@@ -5,7 +5,7 @@ expression: "format!(\"{:#?}\\n\\n========================\\n\\n{:#?}\", env, di
 ---
 Environment {
     store: [
-        Value("add", Function(2, Unknown), (1,4)->(1,7), (1,0)->(1,36)),
+        Value("add", Function(["x", "y"], Unknown), (1,4)->(1,7), (1,0)->(1,36)),
         Value("x", Unknown, (3,4)->(3,5), (3,0)->(3,18)),
     ],
     refs: [

src/eval/snapshots/monkey_language_server__eval__test__expr_after_func_return.snap

@@ -5,7 +5,7 @@ expression: "format!(\"{:#?}\\n\\n========================\\n\\n{:#?}\", env, di
 ---
 Environment {
     store: [
-        Value("add", Function(2, Unknown), (1,4)->(1,7), (1,0)->(4,2)),
+        Value("add", Function(["x", "y"], Unknown), (1,4)->(1,7), (1,0)->(4,2)),
     ],
     refs: [
         Pos("add", "(1,4)->(1,7)"),

src/eval/snapshots/monkey_language_server__eval__test__func_nil_return.snap

@@ -5,7 +5,7 @@ expression: "format!(\"{:#?}\\n\\n========================\\n\\n{:#?}\", env, di
 ---
 Environment {
     store: [
-        Value("f", Function(0, Nil), (1,4)->(1,5), (1,0)->(1,17)),
+        Value("f", Function([], Nil), (1,4)->(1,5), (1,0)->(1,17)),
         Value("a", Nil, (2,4)->(2,5), (2,0)->(2,12)),
     ],
     refs: [

src/eval/snapshots/monkey_language_server__eval__test__nested_scope_funct.snap

@@ -5,8 +5,8 @@ expression: "format!(\"{:#?}\\n\\n========================\\n\\n{:#?}\", env, di
 ---
 Environment {
     store: [
-        Value("add", Function(2, Function(0, Unknown)), (1,4)->(1,7), (1,0)->(7,2)),
-        Value("mult", Function(0, Unknown), (9,4)->(9,8), (9,0)->(9,21)),
+        Value("add", Function(["x", "y"], Function([], Unknown)), (1,4)->(1,7), (1,0)->(7,2)),
+        Value("mult", Function([], Unknown), (9,4)->(9,8), (9,0)->(9,21)),
     ],
     refs: [
         Pos("add", "(1,4)->(1,7)"),