From ac35a5b3ad19735edf714c4f4faf23b42fd899f6 2021-10-07 16:23:40
From: Matthias Bussonnier <bussonniermatthias@gmail.com>
Date: 2021-10-07 16:23:40
Subject: [PATCH] Backport PR #13175: Expand and Fix PDB skip.

---

diff --git a/IPython/core/debugger.py b/IPython/core/debugger.py
index 69cc55f..6d23336 100644
--- a/IPython/core/debugger.py
+++ b/IPython/core/debugger.py
@@ -24,8 +24,12 @@ By default, frames from readonly files will be hidden, frames containing
 Frames containing ``__debuggerskip__`` will be stepped over, frames who's parent
 frames value of ``__debuggerskip__`` is ``True`` will be skipped.
 
-    >>> def helper_1():
+    >>> def helpers_helper():
+    ...     pass
+    ...
+    ... def helper_1():
     ...     print("don't step in me")
+    ...     helpers_helpers() # will be stepped over unless breakpoint set.
     ...
     ...
     ... def helper_2():
@@ -44,6 +48,7 @@ One can define a decorator that wraps a function between the two helpers:
     ...         result = function(*args, **kwargs)
     ...         __debuggerskip__ = True
     ...         helper_2()
+    ...         # setting __debuggerskip__ to False again is not necessary
     ...         return result
     ...
     ...     return wrapped_fn
@@ -892,12 +897,16 @@ class Pdb(OldPdb):
         stop at any point inside the function
 
         """
+
+        sup = super().break_anywhere(frame)
+        if sup:
+            return sup
         if self._predicates["debuggerskip"]:
             if DEBUGGERSKIP in frame.f_code.co_varnames:
                 return True
             if frame.f_back and self._get_frame_locals(frame.f_back).get(DEBUGGERSKIP):
                 return True
-        return super().break_anywhere(frame)
+        return False
 
     @skip_doctest
     def _is_in_decorator_internal_and_should_skip(self, frame):
@@ -916,9 +925,13 @@ class Pdb(OldPdb):
         if DEBUGGERSKIP in frame.f_code.co_varnames:
             return True
 
-        # if parent frame value set to True skip as well.
-        if frame.f_back and self._get_frame_locals(frame.f_back).get(DEBUGGERSKIP):
-            return True
+        # if one of the parent frame value set to True skip as well.
+
+        cframe = frame
+        while getattr(cframe, "f_back", None):
+            cframe = cframe.f_back
+            if self._get_frame_locals(cframe).get(DEBUGGERSKIP):
+                return True
 
         return False
 
diff --git a/IPython/core/tests/test_debugger.py b/IPython/core/tests/test_debugger.py
index 08a2473..eb3b5f3 100644
--- a/IPython/core/tests/test_debugger.py
+++ b/IPython/core/tests/test_debugger.py
@@ -12,6 +12,7 @@ import subprocess
 import sys
 import time
 import warnings
+
 from subprocess import PIPE, CalledProcessError, check_output
 from tempfile import NamedTemporaryFile
 from textwrap import dedent
@@ -328,14 +329,30 @@ def test_xmode_skip():
 
 skip_decorators_blocks = (
     """
+    def helpers_helper():
+        pass # should not stop here except breakpoint
+    """,
+    """
     def helper_1():
-        pass # should not stop here
+        helpers_helper() # should not stop here
     """,
     """
     def helper_2():
         pass # should not stop here
     """,
     """
+    def pdb_skipped_decorator2(function):
+        def wrapped_fn(*args, **kwargs):
+            __debuggerskip__ = True
+            helper_2()
+            __debuggerskip__ = False
+            result = function(*args, **kwargs)
+            __debuggerskip__ = True
+            helper_2()
+            return result
+        return wrapped_fn
+    """,
+    """
     def pdb_skipped_decorator(function):
         def wrapped_fn(*args, **kwargs):
             __debuggerskip__ = True
@@ -349,6 +366,7 @@ skip_decorators_blocks = (
     """,
     """
     @pdb_skipped_decorator
+    @pdb_skipped_decorator2
     def bar(x, y):
         return x * y
     """,
@@ -426,7 +444,7 @@ def test_decorator_skip_disabled():
         ("step", "----> 3         __debuggerskip__"),
         ("step", "----> 4         helper_1()"),
         ("step", "---> 1 def helper_1():"),
-        ("next", "----> 2     pass"),
+        ("next", "----> 2     helpers_helper()"),
         ("next", "--Return--"),
         ("next", "----> 5         __debuggerskip__ = False"),
     ]:
@@ -439,6 +457,62 @@ def test_decorator_skip_disabled():
 
 
 @skip_win32
+def test_decorator_skip_with_breakpoint():
+    """test that decorator frame skipping can be disabled"""
+
+    import pexpect
+
+    env = os.environ.copy()
+    env["IPY_TEST_SIMPLE_PROMPT"] = "1"
+
+    child = pexpect.spawn(
+        sys.executable, ["-m", "IPython", "--colors=nocolor"], env=env
+    )
+    child.timeout = 5 * IPYTHON_TESTING_TIMEOUT_SCALE
+
+    child.expect("IPython")
+    child.expect("\n")
+
+    ### we need a filename, so we need to exec the full block with a filename
+    with NamedTemporaryFile(suffix=".py", dir=".", delete=True) as tf:
+
+        name = tf.name[:-3].split("/")[-1]
+        tf.write("\n".join([dedent(x) for x in skip_decorators_blocks[:-1]]).encode())
+        tf.flush()
+        codeblock = f"from {name} import f"
+
+        dedented_blocks = [
+            codeblock,
+            "f()",
+        ]
+
+        in_prompt_number = 1
+        for cblock in dedented_blocks:
+            child.expect_exact(f"In [{in_prompt_number}]:")
+            in_prompt_number += 1
+            for line in cblock.splitlines():
+                child.sendline(line)
+                child.expect_exact(line)
+            child.sendline("")
+
+        # as the filename does not exists, we'll rely on the filename prompt
+        child.expect_exact("47     bar(3, 4)")
+
+        for input_, expected in [
+            (f"b {name}.py:3", ""),
+            ("step", "1---> 3     pass # should not stop here except"),
+            ("step", "---> 38 @pdb_skipped_decorator"),
+            ("continue", ""),
+        ]:
+            child.expect("ipdb>")
+            child.sendline(input_)
+            child.expect_exact(input_)
+            child.expect_exact(expected)
+
+    child.close()
+
+
+@skip_win32
 def test_where_erase_value():
     """Test that `where` does not access f_locals and erase values."""
     import pexpect