From 81452d870d0548fb7729931ad961b391d6b830f4 Mon Sep 17 00:00:00 2001
From: Gleb Mazovetskiy <glex.spb@gmail.com>
Date: Sat, 17 Aug 2024 08:46:11 +0100
Subject: [PATCH] Add a `StaticVector` pretty-printer for LLDB

---
 .lldbinit                                     |  4 +++
 tools/lldbutils/README.md                     | 17 ++++++++++
 tools/lldbutils/lldbutils/__init__.py         |  6 ++++
 .../pretty_printers/utils/static_vector_pp.py | 32 +++++++++++++++++++
 4 files changed, 59 insertions(+)
 create mode 100644 .lldbinit
 create mode 100644 tools/lldbutils/README.md
 create mode 100644 tools/lldbutils/lldbutils/__init__.py
 create mode 100644 tools/lldbutils/lldbutils/pretty_printers/utils/static_vector_pp.py

diff --git a/.lldbinit b/.lldbinit
new file mode 100644
index 00000000000..6e6a4ef79ae
--- /dev/null
+++ b/.lldbinit
@@ -0,0 +1,4 @@
+script topsrcdir = topsrcdir if "topsrcdir" in locals() else os.getcwd()
+script sys.path.append(os.path.join(topsrcdir, "tools/lldbutils"))
+script import lldbutils
+script lldbutils.init()
diff --git a/tools/lldbutils/README.md b/tools/lldbutils/README.md
new file mode 100644
index 00000000000..2aca048fc3d
--- /dev/null
+++ b/tools/lldbutils/README.md
@@ -0,0 +1,17 @@
+# lldb debugging enhancements
+
+The code in this directory is imported via `.lldbinit`.
+
+Working directory `.lldbinit` is not loaded by default.
+
+You can add the following to `~/.lldbinit` to load it when launching `lldb` from the command line:
+
+```
+settings set target.load-cwd-lldbinit true
+```
+
+If you're using VS Code, you can instead add the following to your configuration:
+
+```json
+"lldb.launch.initCommands": ["command source ${workspaceFolder}/.lldbinit"]
+```
diff --git a/tools/lldbutils/lldbutils/__init__.py b/tools/lldbutils/lldbutils/__init__.py
new file mode 100644
index 00000000000..b49a60da79f
--- /dev/null
+++ b/tools/lldbutils/lldbutils/__init__.py
@@ -0,0 +1,6 @@
+import lldb
+
+import lldbutils.pretty_printers.utils.static_vector_pp
+
+def init():
+  lldbutils.pretty_printers.utils.static_vector_pp.init(lldb.debugger)
diff --git a/tools/lldbutils/lldbutils/pretty_printers/utils/static_vector_pp.py b/tools/lldbutils/lldbutils/pretty_printers/utils/static_vector_pp.py
new file mode 100644
index 00000000000..2f48e2877f8
--- /dev/null
+++ b/tools/lldbutils/lldbutils/pretty_printers/utils/static_vector_pp.py
@@ -0,0 +1,32 @@
+import lldb
+
+
+class StaticVectorSyntheticChildrenProvider:
+    def __init__(self, valobj: lldb.SBValue, internal_dict):
+        self._val: lldb.SBValue = valobj
+        self._size: lldb.SBValue = self._val.GetChildMemberWithName("size_")
+        self._element_type: lldb.SBType = self._val.GetType().GetTemplateArgumentType(0)
+        self._element_size = self._element_type.GetByteSize()
+        self._data_addr = int(
+            self._val.GetChildMemberWithName("data_").GetLoadAddress()
+        )
+
+    def num_children(self, max_children):
+        return self._size.GetValueAsUnsigned(0)
+
+    def get_child_index(self, name):
+        index = int(name)
+        return index if index < self.num_children() else None
+
+    def get_child_at_index(self, index):
+        return self._val.CreateValueFromAddress(
+            f"[{index}]",
+            self._data_addr + self._element_size * index,
+            self._element_type,
+        )
+
+
+def init(debugger: lldb.debugger):
+    debugger.HandleCommand(
+        'type synthetic add -x "devilution::StaticVector<" -l lldbutils.pretty_printers.utils.static_vector_pp.StaticVectorSyntheticChildrenProvider'
+    )