feat: print new files after building (#570)

unit_test/test_wheel_print.py

@@ -0,0 +1,35 @@
+import pytest
+
+from cibuildwheel.util import print_new_wheels
+
+
+def test_printout_wheels(tmp_path, capsys):
+    tmp_path.joinpath("example.0").touch()
+    with print_new_wheels("TEST_MSG: {n}", tmp_path):
+        tmp_path.joinpath("example.1").touch()
+        tmp_path.joinpath("example.2").touch()
+
+    captured = capsys.readouterr()
+    assert captured.err == ""
+
+    assert "example.0" not in captured.out
+    assert "example.1\n" in captured.out
+    assert "example.2\n" in captured.out
+    assert "TEST_MSG:" in captured.out
+    assert "TEST_MSG: 2\n" in captured.out
+
+
+def test_no_printout_on_error(tmp_path, capsys):
+    tmp_path.joinpath("example.0").touch()
+    with pytest.raises(RuntimeError):
+        with print_new_wheels("TEST_MSG: {n}", tmp_path):
+            tmp_path.joinpath("example.1").touch()
+            raise RuntimeError()
+
+    captured = capsys.readouterr()
+    assert captured.err == ""
+
+    assert "example.0" not in captured.out
+    assert "example.1" not in captured.out
+    assert "example.2" not in captured.out
+    assert "TEST_MSG:" not in captured.out