fix bug when heredoc_identifier length exceeds CHAR_MAX

CHANGELOG.md

@@ -7,6 +7,7 @@ fix:
 * allow empty template interpolations
 * allow empty templates
 * fix bug in serializer when the `context_stack.size()` exceeds `CHAR_MAX`
+* fix bug in serializer when the `heredoc_identifier.size()` exceeds `CHAR_MAX`
 
 quality:
 * add fuzzing

src/scanner.cc

@@ -6,6 +6,8 @@
 #include <wctype.h>
 #include <assert.h>
 
+#include <stdio.h>
+
 namespace {
 
 using std::vector;
@@ -49,6 +51,9 @@ public:
       if (size + 2 + it->heredoc_identifier.size() >= TREE_SITTER_SERIALIZATION_BUFFER_SIZE) {
         return 0;
       }
+      if (it->heredoc_identifier.size() > CHAR_MAX) {
+        return 0;
+      }
       buf[size++] = it->type;
       buf[size++] = it->heredoc_identifier.size();
       it->heredoc_identifier.copy(&buf[size], it->heredoc_identifier.size());

test/corpus/templates.txt

@@ -228,3 +228,23 @@ END
             (heredoc_identifier)
             (template_literal)
             (heredoc_identifier)))))))
+
+================================================================================
+heredoc with identifier that does not fit into the serialization buffer (should not crash)
+================================================================================
+
+foo = <<XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
+XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
+
+--------------------------------------------------------------------------------
+
+(config_file
+  (body
+    (attribute
+      (identifier)
+      (expression
+        (template_expr
+          (heredoc_template
+            (heredoc_start)
+            (heredoc_identifier)
+            (heredoc_identifier)))))))