Qt Type Formatters for LLDB

This project adds various type formatters to enable more user friendly display of Qt Core Types in LLDB and IDEs that support it.

Usage

Load the type formatters in LLDB by executing

command script import lldb_qt_formatters

or alternatively place the above line in a .lldbinit file in the root of the project, or in your $HOME directory. To use a project-specific configuration file you will need to enable it

VSCode

VSCode will not source a project .lldbinit file even if you enable it as above. To automatically load the config file, add the following to your launch.json file.

"configurations": [{
    "type": "lldb",
    ...
    "initCommands": [
        "command source ${workspaceFolder}/.lldbinit"
    ]
}]

Supported Types

• QMap<Key, Value>

  auto map = QMap<QString , uint32_t>{
    {"one", 1},
    {"forty-two", 42},
    {"1.21 gigawatts", 1210000}
  };

  (lldb) frame variable map
  (QMap<QString, unsigned int>) map = Size: 3 {
    [0] = {"forty-two": 42}
    [1] = {"1.21 gigawatts": 1210000}
    [2] = {"one": 1}
  }
  

• QMapNode<Key, Value>

• QString

  auto hello = QString("Hello World");

  (lldb) frame variable hello
  (QString) hello = "Hello World"
  

Contribution Guidelines

Contributions are welcomed. See the guide to variable formatting in LLDB, in addition to the existing formatters in the LLDB Source

1. Create a test for your formatter. The tests run LLDB against some sample code and examine the formatted variable output.

2. Implement a new formatter

   • Simple types can be supported with a summary string in the __init__.py file (eg, see support for the QMapNode<Key, Value> type)
   • More complex types can be supported using the Python API (eg QString)
   • Container types such as QMap<> require more elaborate use of the Python API to generate "Synthetic Children"

   Formatters are registered with their types in the __init__.py file.