Use the existing build tag in wheel pack unless overridden

Closes #323. Fixes #322.

1 files changed, 31 insertions, 11 deletions

diff --git a/tests/cli/test_pack.py b/tests/cli/test_pack.py
index 818f817..cb3c58d 100644
--- a/tests/cli/test_pack.py
+++ b/tests/cli/test_pack.py
@@ -11,23 +11,43 @@ TESTWHEEL_PATH = os.path.join(THISDIR, '..', 'testdata', TESTWHEEL_NAME)
 
 
 @pytest.mark.filterwarnings('error:Duplicate name')
-@pytest.mark.parametrize('build_number, filename', [
-    (None, 'test-1.0-py2.py3-none-any.whl'),
-    ('2b', 'test-1.0-2b-py2.py3-none-any.whl')
-], ids=['nobuildnum', 'buildnum'])
-def test_pack(tmpdir_factory, tmpdir, build_number, filename):
-    unpack_dir = str(tmpdir_factory.mktemp('wheeldir'))
+@pytest.mark.parametrize('build_tag_arg, existing_build_tag, filename', [
+    (None, None, 'test-1.0-py2.py3-none-any.whl'),
+    ('2b', None, 'test-1.0-2b-py2.py3-none-any.whl'),
+    (None, '3', 'test-1.0-3-py2.py3-none-any.whl'),
+    ('', '3', 'test-1.0-py2.py3-none-any.whl'),
+], ids=['nobuildnum', 'newbuildarg', 'oldbuildnum', 'erasebuildnum'])
+def test_pack(tmpdir_factory, tmpdir, build_tag_arg, existing_build_tag, filename):
+    unpack_dir = tmpdir_factory.mktemp('wheeldir')
     with ZipFile(TESTWHEEL_PATH) as zf:
         old_record = zf.read('test-1.0.dist-info/RECORD')
-        old_record_lines = sorted(line.rstrip() for line in old_record.split(b'\n') if line)
-        zf.extractall(unpack_dir)
-
-    pack(unpack_dir, str(tmpdir), build_number)
+        old_record_lines = sorted(line.rstrip() for line in old_record.split(b'\n')
+                                  if line and not line.startswith(b'test-1.0.dist-info/WHEEL,'))
+        zf.extractall(str(unpack_dir))
+
+    if existing_build_tag:
+        # Add the build number to WHEEL
+        wheel_file_path = unpack_dir.join('test-1.0.dist-info').join('WHEEL')
+        wheel_file_content = wheel_file_path.read_binary()
+        assert b'Build' not in wheel_file_content
+        wheel_file_content += b'Build: 3\n'
+        wheel_file_path.write(wheel_file_content)
+
+    pack(str(unpack_dir), str(tmpdir), build_tag_arg)
     new_wheel_path = tmpdir.join(filename)
     assert new_wheel_path.isfile()
 
     with ZipFile(str(new_wheel_path)) as zf:
         new_record = zf.read('test-1.0.dist-info/RECORD')
-        new_record_lines = sorted(line.rstrip() for line in new_record.split(b'\n') if line)
+        new_record_lines = sorted(line.rstrip() for line in new_record.split(b'\n')
+                                  if line and not line.startswith(b'test-1.0.dist-info/WHEEL,'))
+
+        new_wheel_file_content = zf.read('test-1.0.dist-info/WHEEL')
 
     assert new_record_lines == old_record_lines
+
+    expected_build_num = build_tag_arg or existing_build_tag
+    if expected_build_num:
+        assert ('Build: %s\n' % expected_build_num).encode() in new_wheel_file_content
+    else:
+        assert b'Build: ' not in new_wheel_file_content