From 8642d894dfcce391f060ac7bdb37f745caad7fdc Mon Sep 17 00:00:00 2001
From: Ed_ <edwardgz@gmail.com>
Date: Tue, 5 May 2026 19:44:40 -0400
Subject: [PATCH] feat(parser): Implement C/C++ update_definition

---
 src/file_cache.py        | 86 ++++++++++++++++++++++++++++++++++++++++
 tests/test_ast_parser.py | 20 ++++++++++
 2 files changed, 106 insertions(+)

diff --git a/src/file_cache.py b/src/file_cache.py
index 924fefa..43b6d2b 100644
--- a/src/file_cache.py
+++ b/src/file_cache.py
@@ -614,6 +614,92 @@ class ASTParser:
   walk(tree.root_node)
   return "\n".join(output)
 
+ def update_definition(self, code: str, name: str, new_content: str, path: Optional[str] = None) -> str:
+  """
+  Surgically replace the definition of a class or function by name.
+  """
+  tree = self.get_cached_tree(path, code)
+
+  def get_name(node: tree_sitter.Node) -> str:
+   name_node = node.child_by_field_name("name")
+   if name_node:
+    return code[name_node.start_byte:name_node.end_byte]
+
+   if node.type == "function_definition":
+    decl = node.child_by_field_name("declarator")
+    while decl:
+     if decl.type in ("identifier", "field_identifier"):
+      return code[decl.start_byte:decl.end_byte]
+     next_decl = decl.child_by_field_name("declarator")
+     if not next_decl and decl.child_count > 0:
+      for child in decl.children:
+       if child.type in ("identifier", "field_identifier"):
+        return code[child.start_byte:child.end_byte]
+      decl = decl.children[0]
+     else:
+      decl = next_decl
+
+   if node.type == "template_declaration":
+    for child in node.children:
+     if child.type in ("function_definition", "class_definition"):
+      return get_name(child)
+
+   if node.type in ("struct_specifier", "class_specifier", "class_definition", "namespace_definition"):
+    for child in node.children:
+     if child.type in ("type_identifier", "identifier", "namespace_identifier"):
+      return code[child.start_byte:child.end_byte]
+   return ""
+
+  parts = re.split(r'::|\.', name)
+
+  def walk(node: tree_sitter.Node, target_parts: List[str]) -> Optional[tree_sitter.Node]:
+   if not target_parts:
+    return None
+   target = target_parts[0]
+   for child in node.children:
+    if child.type in ("function_definition", "class_definition", "class_specifier", "struct_specifier", "namespace_definition", "template_declaration"):
+     if get_name(child) == target:
+      if len(target_parts) == 1:
+       return child
+      body = child.child_by_field_name("body")
+      if not body and child.type == "template_declaration":
+       for sub in child.children:
+        if sub.type in ("function_definition", "class_definition"):
+         body = sub.child_by_field_name("body")
+         break
+      if body:
+       found = walk(body, target_parts[1:])
+       if found: return found
+      for sub in child.children:
+       if sub.type in ("field_declaration_list", "class_body", "declaration_list"):
+        found = walk(sub, target_parts[1:])
+        if found: return found
+   # Recurse for top-level or namespaces
+   if node.type in ("module", "translation_unit", "namespace_definition", "declaration_list"):
+    for child in node.children:
+     if child.type not in ("function_definition", "class_definition", "class_specifier", "struct_specifier", "namespace_definition", "template_declaration"):
+      found = walk(child, target_parts)
+      if found: return found
+   return None
+
+  found_node = walk(tree.root_node, parts)
+  if not found_node and len(parts) == 1:
+   def deep_search(node: tree_sitter.Node, target: str) -> Optional[tree_sitter.Node]:
+    if node.type in ("function_definition", "class_definition", "class_specifier", "struct_specifier", "namespace_definition", "template_declaration"):
+     if get_name(node) == target:
+      return node
+    for child in node.children:
+     res = deep_search(child, target)
+     if res: return res
+    return None
+   found_node = deep_search(tree.root_node, parts[0])
+
+  if found_node:
+   code_bytes = bytearray(code, "utf8")
+   code_bytes[found_node.start_byte:found_node.end_byte] = bytes(new_content, "utf8")
+   return code_bytes.decode("utf8")
+  return f"ERROR: definition '{name}' not found"
+
 def reset_client() -> None:
  pass
 
diff --git a/tests/test_ast_parser.py b/tests/test_ast_parser.py
index c85671f..7f8af49 100644
--- a/tests/test_ast_parser.py
+++ b/tests/test_ast_parser.py
@@ -305,3 +305,23 @@ public:
  assert 'void normalMethod()' in sig2
  assert '{' not in sig2
 
+def test_ast_parser_update_definition_cpp() -> None:
+ """Verify update_definition for C++ including scoped methods."""
+ parser = ASTParser(language="cpp")
+ code = """
+class MyClass {
+public:
+ void myMethod() {
+  int x = 1;
+ }
+};
+"""
+ new_method = """ void myMethod() {
+  int y = 2;
+ }"""
+ updated = parser.update_definition(code, "MyClass::myMethod", new_method)
+ assert 'void myMethod() {' in updated
+ assert 'int y = 2;' in updated
+ assert 'int x = 1;' not in updated
+ assert 'class MyClass {' in updated
+