README

I use Xcode and LLDB to debug my Qt programs, and got tired with there being no visualisation for all the built-in types. Here I endeavour to make all of these types visible through the debugger. Works with Qt 5.x. Tested with Qt 5.9.8, 5.13.2 and XCode 11.

Supported Qt Objects:

Types added via QtFormatters.py

• QString
• QUrl
• QList
• QVector
• QPointer

Types added via QtFormatters.lldb (summary-strings)

• QSize
• QSizeF
• QPoint
• QPointF
• QRect
• QRectF
• QUuid

Types added via qt.py

• QChar
• QByteArray
• QMap (and QMultiMap/QMapNode)
• QHash (and QMultiHash/QHashNode)
• QSet
• QDate
• QTime
• QDateTime

XCode Versions

XCode changed from Python 2.x to Python 3.x at Version 11. If you need XCode 10 or earlier, check out or download the 1.0 Release tag

Installation

git clone this repo somewhere, e.g. ~/qtlldb. Then add the following line to your ~/.lldbinit:

command script import ~/qtlldb/both.py

Running Tests

Two testprojects exist, one for QtCreator and one for XCode: Since the point of this project is to provide Qt Debugging info in XCode, running the XCode project in the debugger verifies that it is working. I guess you could use the QtCreator project to compare and contrast debugger info between XCode and QtCreator

General Notes:

Test project does not produce any output when run.

• lldbtests/lldbtests.pro

  • Open in Qt Creator and build.
  • Step throug main.cpp to see debug info

• lldbtests/XCodeTests.xcodeproj

  • Set path to your Qt Version in XCodeQtConfig.xcconfig
  • Open XCodeTests.xcodeproj in XCode and Build
  • Set a breakpoint on QString Ctor in main.cpp, step over remainder of project to see debug info in XCode.
  • Seems to sometimes do odd things when broken on a line constructing a Qt Object, like show a long list of undefined values.

Testing and Modifying QtFormatters.py

Performance Note I added the exception printing stuff in the printException() method near the top. This required some imports, and I am unsure if this has any performance implications. If you have performance issues, I would suggest commenting out most of printException() and the associated imports.

1. When testing changes to QtFormatters.py you can see compile time errors by manually reloading the file in the XCode Debugger. To do this enter command script import ~/qtlldb/QtFormatters.py in the debugger output window
2. I am not aware of any realtime debugging facilities for this python code, simply use the Python print statement. print("Hello World") in the Python code
3. XCode uses Python3 independent of OSX, see the XCode 11 Release Notes

Modifying the .lldb file

Documentation for adding summary-strings is found at: https://lldb.llvm.org/varformats.html

Origin and Credits

A number of variants of this project exist on bitbucket and Github. As far as I can tell, the earliest is LukeWorth. Notable projects are shown below, with the earliest project last.

Fork	First Commit	Last Commit	Notes
[https://github.com/SteveSchilz/lldb-qt-formatters]	2019-12-10	2019-12-11	Updated for XCode 11/Python 3
[https://github.com/pavolmarkovic-serato/lldb-qt-formatters]	2016-12-12	2016-12-12	Direct fork of LukeWorth, including commit history
[https://github.com/ivany4/lldb-qt]	2016-02-25	2016-02-25	Works with Qt4, same code, different attribution
[https://bitbucket.org/lukeworth/lldb-qt-formatters/src/default/]	2015-10-16	2015-10-16	Apears to be earliest version of this code

Origin and Credits, part 2

I've pulled in a couple of files from the KDE Repository here. These handle some of the more complex types (QMap, QHash, and QSet), but don't seem to correctly handle QString in Qt 5.14.2, hence the need for both. (I spent a bit of time trying to fix the QString handling in the kde files, but neither Qt nor python is my specialty, and I needed to get back to my actual work. :) ) I've modified the kde files to use urllib.parse instead of urlparse (to fix an error I was seeing on Mac OS X 10.15), and disabled installation of handlers for the types that QtFormatters.py also handles.

I haven't integrated the two .py files together, partially because the ones from the kde repository have a GPL license attached, and it's not clear what the license on QtFormatters is. Loading both .py files seems to get me the results I want in the cases I've tested, so I'm just using them as-is.