From d87a60c54453763476845138133ad7da54c159a7 Mon Sep 17 00:00:00 2001
From: user202729 <25191436+user202729@users.noreply.github.com>
Date: Mon, 24 Mar 2025 10:38:12 +0700
Subject: [PATCH 1/2] Safeguard _sage_getargspec_cython

---
This patch was taken from: https://github.com/sagemath/sage/pull/39776
It will be released in version 10.7 and can be removed after the upgrade.

 src/sage/misc/sageinspect.py | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/src/sage/misc/sageinspect.py b/src/sage/misc/sageinspect.py
index 6fc0e29551f..d25f1f81820 100644
--- a/src/sage/misc/sageinspect.py
+++ b/src/sage/misc/sageinspect.py
@@ -1139,6 +1139,11 @@ def _sage_getargspec_cython(source):
                     defaults=('a string', {(1, 2, 3): True}),
                     kwonlyargs=[], kwonlydefaults=None, annotations={})
     """
+    if not isinstance(source, str):
+        # the caller ought to ensure this, but if it forgets (e.g. passing None),
+        # we raise the correct exception type to avoid confusing error message
+        # and possible further hard-to-debug errors, see :issue:`39735`
+        raise TypeError
     defpos = source.find('def ')
     assert defpos > -1, "The given source does not contain 'def'"
     s = source[defpos:].strip()

From 21dd8224fca8a70490c754309350d08f56178809 Mon Sep 17 00:00:00 2001
From: user202729 <25191436+user202729@users.noreply.github.com>
Date: Thu, 27 Mar 2025 22:58:22 +0700
Subject: [PATCH 2/2] Change to AssertionError and handle issue upstream

---
 src/sage/misc/sageinspect.py | 22 ++++++++++++----------
 1 file changed, 12 insertions(+), 10 deletions(-)

diff --git a/src/sage/misc/sageinspect.py b/src/sage/misc/sageinspect.py
index b617e288b97..bb704d74075 100644
--- a/src/sage/misc/sageinspect.py
+++ b/src/sage/misc/sageinspect.py
@@ -1140,11 +1140,10 @@ def _sage_getargspec_cython(source):
                     defaults=('a string', {(1, 2, 3): True}),
                     kwonlyargs=[], kwonlydefaults=None, annotations={})
     """
-    if not isinstance(source, str):
-        # the caller ought to ensure this, but if it forgets (e.g. passing None),
-        # we raise the correct exception type to avoid confusing error message
-        # and possible further hard-to-debug errors, see :issue:`39735`
-        raise TypeError
+    assert isinstance(source, str)
+    # the caller ought to ensure this, but if it forgets (e.g. passing None),
+    # we avoid raising AttributeError to avoid confusing error message
+    # and possible further hard-to-debug errors, see :issue:`39735`
     defpos = source.find('def ')
     assert defpos > -1, "The given source does not contain 'def'"
     s = source[defpos:].strip()
@@ -1682,12 +1681,15 @@ def foo(x, a='\')"', b={not (2+1==3):'bar'}): return
         except TypeError:  # arg is not a code object
             # The above "hopefully" was wishful thinking:
             try:
-                return inspect.FullArgSpec(*_sage_getargspec_cython(sage_getsource(obj)))
+                source = sage_getsource(obj)
             except TypeError:  # This happens for Python builtins
-                # The best we can do is to return a generic argspec
-                args = []
-                varargs = 'args'
-                varkw = 'kwds'
+                source = None
+            if source is not None:
+                return inspect.FullArgSpec(*_sage_getargspec_cython(source))
+            # The best we can do is to return a generic argspec
+            args = []
+            varargs = 'args'
+            varkw = 'kwds'
     try:
         defaults = func_obj.__defaults__
     except AttributeError: