From 62ed6acd24ec605bc90652bd9ee8e18ca66e8aab Mon Sep 17 00:00:00 2001
From: KakarotCake <KakarottoCake@users.noreply.github.com>
Date: Wed, 29 Jul 2026 03:40:30 -0400
Subject: [PATCH] fix: sanitize empty and numeric identifiers

---
 gcrecomp-core/src/recompiler/codegen/mod.rs | 17 +++++++++++++++--
 gcrecomp-core/tests/codegen_test.rs         |  6 ++++++
 2 files changed, 21 insertions(+), 2 deletions(-)

diff --git a/gcrecomp-core/src/recompiler/codegen/mod.rs b/gcrecomp-core/src/recompiler/codegen/mod.rs
index 838497e..c8e379b 100644
--- a/gcrecomp-core/src/recompiler/codegen/mod.rs
+++ b/gcrecomp-core/src/recompiler/codegen/mod.rs
@@ -1209,10 +1209,23 @@ impl CodeGenerator {
     }
 
     pub fn sanitize_identifier(&self, name: &str) -> String {
-        name.replace([' ', '-', '.'], "_")
+        let mut identifier: String = name
+            .replace([' ', '-', '.'], "_")
             .chars()
             .filter(|c| c.is_alphanumeric() || *c == '_')
-            .collect()
+            .collect();
+
+        if identifier.is_empty() {
+            identifier.push_str("function");
+        } else if identifier
+            .chars()
+            .next()
+            .is_some_and(|character| character.is_numeric())
+        {
+            identifier.insert_str(0, "function_");
+        }
+
+        identifier
     }
 
     fn indent(&self) -> String {
diff --git a/gcrecomp-core/tests/codegen_test.rs b/gcrecomp-core/tests/codegen_test.rs
index c39b64a..bf93649 100644
--- a/gcrecomp-core/tests/codegen_test.rs
+++ b/gcrecomp-core/tests/codegen_test.rs
@@ -168,6 +168,11 @@ fn test_mtctr_sets_ctr() {
 fn test_sanitize_identifier() {
     let codegen = CodeGenerator::new();
 
+    assert_eq!(codegen.sanitize_identifier(""), "function");
+    assert_eq!(
+        codegen.sanitize_identifier("123_example"),
+        "function_123_example"
+    );
     assert_eq!(
         codegen.sanitize_identifier("test_function"),
         "test_function"
@@ -184,4 +189,5 @@ fn test_sanitize_identifier() {
         codegen.sanitize_identifier("test function"),
         "test_function"
     );
+    assert_eq!(codegen.sanitize_identifier("@@@"), "function");
 }