fix: 3.11.0b4 has 0-numbered lines. Fixes #1419

CPython added these lines in
https://github.com/python/cpython/commit/1bfe83a114da3939c00746fc44dc5da7f56f525f

2 files changed, 4 insertions, 1 deletions

diff --git a/coverage/env.py b/coverage/env.py
index 444cb892..2e21b9a7 100644
--- a/coverage/env.py
+++ b/coverage/env.py
@@ -110,6 +110,9 @@ class PYBEHAVIOR:
     # Some words are keywords in some places, identifiers in other places.
     soft_keywords = (PYVERSION >= (3, 10))
 
+    # Modules start with a line numbered zero. This means empty modules have
+    # only a 0-number line, which is ignored, giving a truly empty module.
+    empty_is_empty = (PYVERSION >= (3, 11, 0, 'beta', 4))
 
 # Coverage.py specifics.
 
diff --git a/coverage/parser.py b/coverage/parser.py
index dce4f937..7ef67d2c 100644
--- a/coverage/parser.py
+++ b/coverage/parser.py
@@ -377,7 +377,7 @@ class ByteParser:
         """
         if hasattr(self.code, "co_lines"):
             for _, _, line in self.code.co_lines():
-                if line is not None:
+                if line:
                     yield line
         else:
             # Adapted from dis.py in the standard library.