Issue #21217: inspect.getsourcelines() now tries to compute the start and

end lines from the code object, fixing an issue when a lambda function is
used as decorator argument.  Patch by Thomas Ballinger.

Lib/inspect.py

@@ -32,6 +32,7 @@ __author__ = ('Ka-Ping Yee <ping@lfw.org>',
               'Yury Selivanov <yselivanov@sprymix.com>')
 
 import ast
+import dis
 import enum
 import importlib.machinery
 import itertools
@@ -49,18 +50,10 @@ from operator import attrgetter
 from collections import namedtuple, OrderedDict
 
 # Create constants for the compiler flags in Include/code.h
-# We try to get them from dis to avoid duplication, but fall
-# back to hard-coding so the dependency is optional
-try:
-    from dis import COMPILER_FLAG_NAMES as _flag_names
-except ImportError:
-    CO_OPTIMIZED, CO_NEWLOCALS = 0x1, 0x2
-    CO_VARARGS, CO_VARKEYWORDS = 0x4, 0x8
-    CO_NESTED, CO_GENERATOR, CO_NOFREE = 0x10, 0x20, 0x40
-else:
-    mod_dict = globals()
-    for k, v in _flag_names.items():
-        mod_dict["CO_" + v] = k
+# We try to get them from dis to avoid duplication
+mod_dict = globals()
+for k, v in dis.COMPILER_FLAG_NAMES.items():
+    mod_dict["CO_" + v] = k
 
 # See Include/object.h
 TPFLAGS_IS_ABSTRACT = 1 << 20
@@ -888,6 +881,14 @@ def getblock(lines):
         pass
     return lines[:blockfinder.last]
 
+def _line_number_helper(code_obj, lines, lnum):
+    """Return a list of source lines and starting line number for a code object.
+
+    The arguments must be a code object with lines and lnum from findsource.
+    """
+    _, end_line = list(dis.findlinestarts(code_obj))[-1]
+    return lines[lnum:end_line], lnum + 1
+
 def getsourcelines(object):
     """Return a list of source lines and starting line number for an object.
 
@@ -899,8 +900,16 @@ def getsourcelines(object):
     object = unwrap(object)
     lines, lnum = findsource(object)
 
-    if ismodule(object): return lines, 0
-    else: return getblock(lines[lnum:]), lnum + 1
+    if ismodule(object):
+        return lines, 0
+    elif iscode(object):
+        return _line_number_helper(object, lines, lnum)
+    elif isfunction(object):
+        return _line_number_helper(object.__code__, lines, lnum)
+    elif ismethod(object):
+        return _line_number_helper(object.__func__.__code__, lines, lnum)
+    else:
+        return getblock(lines[lnum:]), lnum + 1
 
 def getsource(object):
     """Return the text of the source code for an object.