bpo-42562: Fix issue when dis failed to parse function that has no line numbers (GH-23632)
Fix issue when dis failed to parse function that has only annotations
diff --git a/Lib/dis.py b/Lib/dis.py
index ea50f56..ccbd65b 100644
--- a/Lib/dis.py
+++ b/Lib/dis.py
@@ -384,7 +384,7 @@
constants=None, cells=None, linestarts=None,
*, file=None, line_offset=0):
# Omit the line number column entirely if we have no line number info
- show_lineno = linestarts is not None
+ show_lineno = bool(linestarts)
if show_lineno:
maxlineno = max(linestarts.values()) + line_offset
if maxlineno >= 1000:
diff --git a/Lib/test/test_dis.py b/Lib/test/test_dis.py
index d0743d6..56d8771 100644
--- a/Lib/test/test_dis.py
+++ b/Lib/test/test_dis.py
@@ -166,6 +166,20 @@
bug1333982.__code__.co_firstlineno + 2,
bug1333982.__code__.co_firstlineno + 1)
+
+def bug42562():
+ pass
+
+
+# Set line number for 'pass' to None
+bug42562.__code__ = bug42562.__code__.replace(co_linetable=b'\x04\x80\xff\x80')
+
+
+dis_bug42562 = """\
+ 0 LOAD_CONST 0 (None)
+ 2 RETURN_VALUE
+"""
+
_BIG_LINENO_FORMAT = """\
%3d 0 LOAD_GLOBAL 0 (spam)
2 POP_TOP
@@ -520,6 +534,9 @@
self.do_disassembly_test(bug1333982, dis_bug1333982)
+ def test_bug_42562(self):
+ self.do_disassembly_test(bug42562, dis_bug42562)
+
def test_big_linenos(self):
def func(count):
namespace = {}
diff --git a/Misc/NEWS.d/next/Library/2020-12-03-22-42-03.bpo-42562.2hPmhi.rst b/Misc/NEWS.d/next/Library/2020-12-03-22-42-03.bpo-42562.2hPmhi.rst
new file mode 100644
index 0000000..4999da5
--- /dev/null
+++ b/Misc/NEWS.d/next/Library/2020-12-03-22-42-03.bpo-42562.2hPmhi.rst
@@ -0,0 +1,2 @@
+Fix issue when dis failed to parse function that has no line numbers. Patch
+provided by Yurii Karabas.