From da93f26fa66bcadfc15f6033d1acd1fce2d73525 Mon Sep 17 00:00:00 2001
From: Alexander Medvednikov <alexander@medvednikov.com>
Date: Thu, 23 Apr 2026 21:56:08 +0300
Subject: [PATCH] jsgen: fix Playground `@LOCATION` and `@FILE_LINE`
 interpolation problems (fixes #23554)

---
 vlib/v/gen/js/js.v         |  4 ++++
 vlib/v/gen/js/jsgen_test.v | 23 +++++++++++++++++++++++
 vlib/v/gen/js/str.v        |  4 ++++
 3 files changed, 31 insertions(+)

diff --git a/vlib/v/gen/js/js.v b/vlib/v/gen/js/js.v
index e5c606ddc..3937286fd 100644
--- a/vlib/v/gen/js/js.v
+++ b/vlib/v/gen/js/js.v
@@ -3639,6 +3639,10 @@ fn (mut g JsGen) gen_string_inter_literal(it ast.StringInterLiteral) {
 			continue
 		}
 		expr := it.exprs[i]
+		if expr is ast.AtExpr {
+			g.write(escape_template_literal_value(expr.val))
+			continue
+		}
 		// fmt := it.fmts[i]
 		// fwidth := it.fwidths[i]
 		// precision := it.precisions[i]
diff --git a/vlib/v/gen/js/jsgen_test.v b/vlib/v/gen/js/jsgen_test.v
index 91e90bfbf..be0d322f2 100644
--- a/vlib/v/gen/js/jsgen_test.v
+++ b/vlib/v/gen/js/jsgen_test.v
@@ -88,6 +88,29 @@ fn test_issue_20667_js_can_compile_game_of_life_example() {
 	assert os.exists(output)
 }
 
+fn test_issue_23554_js_browser_interpolated_at_exprs_do_not_emit_nested_templates() {
+	vexe := os.getenv('VEXE')
+	os.chdir(os.dir(vexe)) or {}
+	os.mkdir_all(output_dir) or { panic(err) }
+	program := os.join_path(output_dir, 'issue_23554.v')
+	output := os.join_path(output_dir, 'issue_23554.js')
+	source := [
+		'fn main() {',
+		"\tprintln('\${@LOCATION}')",
+		"\tprintln('\${@FILE_LINE}')",
+		"\tprintln('X \${@LOCATION}')",
+		"\tprintln('X \${@FILE_LINE}')",
+		'}',
+	].join_lines()
+	os.write_file(program, source) or { panic(err) }
+	res :=
+		os.execute('${os.quoted_path(vexe)} -b js_browser -o ${os.quoted_path(output)} ${os.quoted_path(program)}')
+	assert res.exit_code == 0, res.output
+	js := os.read_file(output) or { panic(err) }
+	assert !js.contains('new string(`' + '$' + '{"')
+	assert os.exists(output)
+}
+
 fn find_test_files() []string {
 	files := os.ls(test_dir) or { panic(err) }
 	// The life example never exits, so tests would hang with it, skip
diff --git a/vlib/v/gen/js/str.v b/vlib/v/gen/js/str.v
index 2421f3120..f13712cc9 100644
--- a/vlib/v/gen/js/str.v
+++ b/vlib/v/gen/js/str.v
@@ -2,6 +2,10 @@ module js
 
 import v.ast
 
+fn escape_template_literal_value(s string) string {
+	return s.replace('\\', '\\\\').replace('`', '\\`').replace('$' + '{', '\\' + '$' + '{')
+}
+
 /*
 fn (mut g JsGen) gen_expr_to_string(expr ast.Expr, etype ast.Type) {
 	is_shared := etype.has_flag(.shared_f)
-- 
2.39.5