fix(lldb): clang ast formatters

Author: alandefreitas

bootstrap.py

@@ -2509,6 +2509,7 @@ def generate_pretty_printer_configs(self):
                 lldbinit_content += f"# \n"
             lldbinit_content += f"command script import {os.path.join(self.options.llvm_src_dir, 'llvm', 'utils', 'lldbDataFormatters.py').replace(os.sep, '/')}\n"
             lldbinit_content += f"command script import {os.path.join(self.options.mrdocs_src_dir, 'share', 'lldb', 'mrdocs_formatters.py').replace(os.sep, '/')}\n"
+            lldbinit_content += f"command script import {os.path.join(self.options.mrdocs_src_dir, 'share', 'lldb', 'clang_ast_formatters.py').replace(os.sep, '/')}\n"
             with open(lldbinit_path, "w") as f:
                 f.write(lldbinit_content)
             print(f"Generated LLDB pretty printer configuration at '{lldbinit_path}'")

share/lldb/clang_ast_formatters.py

@@ -0,0 +1,150 @@
+#
+# Copyright (c) 2025 alandefreitas ([email protected])
+#
+# Distributed under the Boost Software License, Version 1.0.
+# https://www.boost.org/LICENSE_1_0.txt
+#
+
+import lldb
+import re
+
+
+# ---------- tiny helpers ----------
+def _ctx(v):
+    try:
+        return v.Dereference() if v.TypeIsPointerType() else v
+    except Exception:
+        return v
+
+def _eval_str(scope, code):
+    opts = lldb.SBExpressionOptions()
+    opts.SetLanguage(lldb.eLanguageTypeC_plus_plus)
+    opts.SetCoerceResultToId(False)
+    r = scope.EvaluateExpression(code, opts)
+    if r and r.GetError() and r.GetError().Success():
+        s = r.GetSummary() or r.GetValue()
+        return s.strip('"') if s else None
+    return None
+
+def _strip_ptr_ref(t):  # SBType -> SBType (no pointers/refs)
+    try:
+        # Drop references if possible
+        dt = t.GetDereferencedType()
+        if dt and dt.IsValid():  # only valid for refs
+            t = dt
+        # Drop pointers
+        while t.IsPointerType():
+            t = t.GetPointeeType()
+    except Exception:
+        pass
+    return t
+
+def _kind_from_type(valobj):
+    t = _strip_ptr_ref(valobj.GetType())
+    name = t.GetName() or ""
+    m = re.search(r'clang::([A-Za-z_0-9]+)Decl', name)
+    return m.group(1) if m else "Decl"
+
+def _humanize_kind(kind: str) -> str:
+    # Insert spaces at transitions: a|A, A|A a, digit|A; then lowercase.
+    if not kind:
+        return "decl"
+    s = re.sub(r'(?<=[a-z0-9])(?=[A-Z])', ' ', kind)
+    s = re.sub(r'(?<=[A-Z])(?=[A-Z][a-z])', ' ', s)
+    return s.lower()
+
+def _is_derived_from(sbtype: lldb.SBType, qualified_basename: str) -> bool:
+    """Walk base classes to see if sbtype derives from qualified_basename."""
+    try:
+        t = _strip_ptr_ref(sbtype)
+        seen = set()
+        q = [t]
+        steps = 0
+        while q and steps < 128:
+            steps += 1
+            cur = q.pop()
+            n = cur.GetName() or ""
+            if n == qualified_basename or n.endswith("::" + qualified_basename.split("::")[-1]):
+                # Accept exact or namespaced matches
+                if n.endswith(qualified_basename):
+                    return True
+            num = cur.GetNumberOfDirectBaseClasses()
+            for i in range(num):
+                m = cur.GetDirectBaseClassAtIndex(i)  # SBTypeMember
+                bt = m.GetType()
+                if bt and bt.IsValid():
+                    bn = bt.GetName() or ""
+                    if bn not in seen:
+                        seen.add(bn)
+                        q.append(bt)
+    except Exception:
+        pass
+    return False
+
+
+# ---------- recognizers ----------
+def is_clang_nameddecl(sbtype, _dict):
+    t = _strip_ptr_ref(sbtype)
+    n = t.GetName() or ""
+    if not n.startswith("clang::"):
+        return False
+    return _is_derived_from(t, "clang::NamedDecl")
+
+def is_clang_decl_not_named(sbtype, _dict):
+    t = _strip_ptr_ref(sbtype)
+    n = t.GetName() or ""
+    if not n.startswith("clang::"):
+        return False
+    # Must be a Decl, but NOT a NamedDecl
+    return _is_derived_from(t, "clang::Decl") and not _is_derived_from(t, "clang::NamedDecl")
+
+
+# ---------- summaries ----------
+# NamedDecl (qualified name + humanized kind)
+def NamedDecl_summary(valobj, _dict):
+    o = _ctx(valobj)
+
+    # Qualified name first
+    q = _eval_str(o, "static_cast<const ::clang::NamedDecl*>(this)->getQualifiedNameAsString()")
+    if not q:
+        q = _eval_str(o, "static_cast<const ::clang::NamedDecl*>(this)->getNameAsString()")
+
+    # Anonymous namespace friendly label (for the rare case q is still empty)
+    if not q:
+        anon = _eval_str(
+            o,
+            "(static_cast<const ::clang::NamespaceDecl*>(this)->isAnonymousNamespace() "
+            "? std::string(\"(anonymous namespace)\") : std::string())"
+        )
+        if anon:
+            q = anon
+
+    # Decl kind → humanized lowercase
+    kind = _eval_str(o, "std::string(getDeclKindName())") or _kind_from_type(valobj)
+    hkind = _humanize_kind(kind)
+
+    return f"{q} ({hkind})" if q else f"<unnamed> ({hkind})"
+
+
+# Non-NamedDecl (unnamed) → "<unnamed> (humanized kind)"
+def UnnamedDecl_summary(valobj, _dict):
+    o = _ctx(valobj)
+    kind = _eval_str(o, "std::string(getDeclKindName())") or _kind_from_type(valobj)
+    hkind = _humanize_kind(kind)
+    return f"<unnamed> ({hkind})"
+
+
+def __lldb_init_module(debugger, _dict):
+    # One rule for ALL NamedDecl-derived types
+    debugger.HandleCommand(
+        'type summary add '
+        '--python-function clang_ast_formatters.NamedDecl_summary '
+        '--recognizer-function clang_ast_formatters.is_clang_nameddecl'
+    )
+    # And a second rule for other Decl types (non-NamedDecl)
+    debugger.HandleCommand(
+        'type summary add '
+        '--python-function clang_ast_formatters.UnnamedDecl_summary '
+        '--recognizer-function clang_ast_formatters.is_clang_decl_not_named'
+    )
+    print("[clang-ast] NamedDecl and Unnamed Decl summaries registered via recognizers.")