From 2bf59b14d12c9b4abccaf74ef269813091db091e Mon Sep 17 00:00:00 2001
From: Delyan Angelov <delian66@gmail.com>
Date: Fri, 23 Aug 2024 13:40:38 +0300
Subject: [PATCH] ast: cache ident lookups for consts in ast Expr str (#22101)

---
 vlib/v/ast/ast.v |  1 +
 vlib/v/ast/str.v | 15 ++++++++++++---
 2 files changed, 13 insertions(+), 3 deletions(-)

diff --git a/vlib/v/ast/ast.v b/vlib/v/ast/ast.v
index 009b5f7c9b..14cfe95606 100644
--- a/vlib/v/ast/ast.v
+++ b/vlib/v/ast/ast.v
@@ -1025,6 +1025,7 @@ pub mut:
 	mod            string
 	name           string
 	full_name      string
+	cached_name    string
 	kind           IdentKind
 	info           IdentInfo
 	is_mut         bool // if mut *token* is before name. Use `is_mut()` to lookup mut variable
diff --git a/vlib/v/ast/str.v b/vlib/v/ast/str.v
index 1b1063cc00..fdbc6560da 100644
--- a/vlib/v/ast/str.v
+++ b/vlib/v/ast/str.v
@@ -395,7 +395,7 @@ __global nested_expr_str_calls = i64(0)
 const max_nested_expr_str_calls = 300
 
 // string representation of expr
-pub fn (x Expr) str() string {
+pub fn (x &Expr) str() string {
 	str_calls := stdatomic.add_i64(&nested_expr_str_calls, 1)
 	if str_calls > ast.max_nested_expr_str_calls {
 		$if panic_on_deeply_nested_expr_str_calls ? {
@@ -515,13 +515,22 @@ pub fn (x Expr) str() string {
 			return 'spawn ${x.call_expr}'
 		}
 		Ident {
+			if x.cached_name != '' {
+				return x.cached_name
+			}
 			if obj := x.scope.find('${x.mod}.${x.name}') {
 				if obj is ConstField && x.mod != 'main' {
 					last_mod := x.mod.all_after_last('.')
-					return '${last_mod}.${x.name}'
+					unsafe {
+						x.cached_name = '${last_mod}.${x.name}'
+					}
+					return x.cached_name
 				}
 			}
-			return x.name.clone()
+			unsafe {
+				x.cached_name = x.name.clone()
+			}
+			return x.cached_name
 		}
 		IfExpr {
 			mut parts := []string{}