[lldb] Update test.rst with a paragraph about pdb
Debugging tests sometimes involves debugging the Python source. This adds a paragraph to
the "Debugging Test Failures" section about using `pdb`, and also describes how to run
lldb commands from pdb.
Differential Revision: https://reviews.llvm.org/D99744
GitOrigin-RevId: 0c653d4c3d1426267337576ab202bb594144111c
diff --git a/docs/resources/test.rst b/docs/resources/test.rst
index e066f8e..2c08ddd 100644
--- a/docs/resources/test.rst
+++ b/docs/resources/test.rst
@@ -373,7 +373,20 @@
-----------------------
On non-Windows platforms, you can use the ``-d`` option to ``dotest.py`` which
-will cause the script to wait for a while until a debugger is attached.
+will cause the script to print out the pid of the test and wait for a while
+until a debugger is attached. Then run ``lldb -p <pid>`` to attach.
+
+To instead debug a test's python source, edit the test and insert
+``import pdb; pdb.set_trace()`` at the point you want to start debugging. In
+addition to pdb's debugging facilities, lldb commands can be executed with the
+help of a pdb alias. For example ``lldb bt`` and ``lldb v some_var``. Add this
+line to your ``~/.pdbrc``:
+
+::
+
+ alias lldb self.dbg.HandleCommand("%*")
+
+::
Debugging Test Failures on Windows
``````````````````````````````````
