fix test failures where temporary dataset suffix was incorrect

Author: Kyle A Logue

sigmf/sigmffile.py

@@ -938,8 +938,8 @@ def get_dataset_filename_from_metadata(meta_fn, metadata=None):
     Parse provided metadata and return the expected data filename. In the case of
     a metadata only distribution, or if the file does not exist, this will return
     'None'. The priority for conflicting:
-        1. The file named <METAFILE_BASENAME>.sigmf-data if it exists
-        2. The file in the `core:dataset` field (Non-Compliant Dataset) if it exists
+        1. The file named <stem>.SIGMF_DATASET_EXT if it exists
+        2. The file in the DATASET_KEY field (Non-Compliant Dataset) if it exists
         3. None (may be a metadata only distribution)
     """
     compliant_filename = get_sigmf_filenames(meta_fn)["data_fn"]

tests/conftest.py

@@ -11,15 +11,16 @@
 import pytest
 
 from sigmf import __specification__
+from sigmf.archive import SIGMF_DATASET_EXT
 from sigmf.sigmffile import SigMFFile
 
 from .testdata import TEST_FLOAT32_DATA, TEST_METADATA
 
 
 @pytest.fixture
 def test_data_file():
-    """when called, yields temporary file"""
-    with tempfile.NamedTemporaryFile() as temp:
+    """when called, yields temporary dataset"""
+    with tempfile.NamedTemporaryFile(suffix=f".{SIGMF_DATASET_EXT}") as temp:
         TEST_FLOAT32_DATA.tofile(temp.name)
         yield temp