Fix bug with missing negative line numbers on PyPy3 7.1 #943

Author: nedbat

CHANGES.rst

@@ -26,6 +26,10 @@ Unreleased
 
 - Updated Python 3.9 support to 3.9a3.
 
+- Fixed a bug with missing negative line numbers on PyPy3 7.1 (`issue 943`_).
+
+.. _issue 943: https://github.com/nedbat/coveragepy/issues/943
+
 
 .. _changes_503:
 

coverage/env.py

@@ -57,7 +57,7 @@ class PYBEHAVIOR(object):
     unpackings_pep448 = (PYVERSION >= (3, 5))
 
     # Can co_lnotab have negative deltas?
-    negative_lnotab = (PYVERSION >= (3, 6))
+    negative_lnotab = (PYVERSION >= (3, 6)) and (PYPYVERSION >= (7, 2))
 
     # Do .pyc files conform to PEP 552? Hash-based pyc's.
     hashed_pyc_pep552 = (PYVERSION >= (3, 7, 0, 'alpha', 4))