From d53e40d3f4b7f0caa403519a4169376e1f5ce860 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Kha=C3=AFs=20COLIN?= <khais.colin@gmail.com>
Date: Wed, 16 Apr 2025 17:36:51 +0200
Subject: [PATCH] fix(subst/variable): invalid identifiers were having their $
 swallowed

It is safe to delete this part:
```c
if (!rep)
   return (NULL);
```
because rep is always returned, and no other code depends on that value
---
 src/subst/variable_subst.c |  8 ++++----
 test.sh                    | 16 ++++++++++++++++
 2 files changed, 20 insertions(+), 4 deletions(-)

diff --git a/src/subst/variable_subst.c b/src/subst/variable_subst.c
index 9415519..96f903f 100644
--- a/src/subst/variable_subst.c
+++ b/src/subst/variable_subst.c
@@ -5,8 +5,8 @@
 /*                                                    +:+ +:+         +:+     */
 /*   By: khais <marvin@42.fr>                       +#+  +:+       +#+        */
 /*                                                +#+#+#+#+#+   +#+           */
-/*   Created: 2025/03/19 17:28/29 by khais             #+#    #+#             */
-/*   Updated: 2025/03/24 10:52:10 by jguelen          ###   ########.fr       */
+/*   Created: 2025/03/19 17:28:29 by khais             #+#    #+#             */
+/*   Updated: 2025/04/16 17:45:36 by khais            ###   ########.fr       */
 /*                                                                            */
 /* ************************************************************************** */
 
@@ -95,9 +95,9 @@ static char	*calculate_replacement(t_worddesc *word, t_minishell *app, size_t i,
 	{
 		*id_len = 1;
 		rep = expand_question_mark(app);
-		if (!rep)
-			return (NULL);
 	}
+	else if (*id_len == 0)
+		return (free(id), ft_strdup("$"));
 	else
 	{
 		rep = env_get_val(app->env, id);
diff --git a/test.sh b/test.sh
index dbf2a1c..09202fe 100755
--- a/test.sh
+++ b/test.sh
@@ -658,4 +658,20 @@ expecting <<EOF
 hi
 EOF
 
+when_run <<EOF "variable substitution with no valid name is not substitued"
+echo \$=
+echo \$:
+EOF
+expecting <<EOF
+$=
+$:
+EOF
+
+when_run <<EOF "variable substitution with a lone dollar sign"
+echo " $ " | cat -e
+EOF
+expecting <<EOF
+ $ $
+EOF
+
 finalize