From 489b2071f612d90b67afd0b5961d14ad9ff07b2b 2020-07-18 20:35:12
From: Matthias Bussonnier <bussonniermatthias@gmail.com>
Date: 2020-07-18 20:35:12
Subject: [PATCH] Backport PR #12453: Allow spaces when using debug magic

---

diff --git a/IPython/core/magics/execution.py b/IPython/core/magics/execution.py
index dc6cdf0..a7ca07b 100644
--- a/IPython/core/magics/execution.py
+++ b/IPython/core/magics/execution.py
@@ -467,7 +467,13 @@ python-profiler package from non-free.""")
 
         if not (args.breakpoint or args.statement or cell):
             self._debug_post_mortem()
+        elif not (args.breakpoint or cell):
+            # If there is no breakpoints, the line is just code to execute
+            self._debug_exec(line, None)
         else:
+            # Here we try to reconstruct the code from the output of
+            # parse_argstring. This might not work if the code has spaces
+            # For example this fails for `print("a b")`
             code = "\n".join(args.statement)
             if cell:
                 code += "\n" + cell
diff --git a/IPython/core/tests/test_magic.py b/IPython/core/tests/test_magic.py
index 877326c..d6e5d2f 100644
--- a/IPython/core/tests/test_magic.py
+++ b/IPython/core/tests/test_magic.py
@@ -32,6 +32,7 @@ from IPython.utils.io import capture_output
 from IPython.utils.tempdir import (TemporaryDirectory,
                                     TemporaryWorkingDirectory)
 from IPython.utils.process import find_cmd
+from .test_debugger import PdbTestInput
 
 
 @magic.magics_class
@@ -622,6 +623,18 @@ def doctest_precision():
     Out[5]: '3.141593e+00'
     """
 
+def test_debug_magic():
+    """Test debugging a small code with %debug
+    
+    In [1]: with PdbTestInput(['c']):
+       ...:     %debug print("a b") #doctest: +ELLIPSIS
+       ...:
+    ...
+    ipdb> c
+    a b
+    In [2]:
+    """
+
 def test_psearch():
     with tt.AssertPrints("dict.fromkeys"):
         _ip.run_cell("dict.fr*?")