chore(tests): Improve tests

pyreaddbc/readdbc.py

@@ -18,7 +18,7 @@
     from ._readdbc import ffi, lib
 
 
-def read_dbc(filename, encoding="iso-8859-1", raw=False):
+def read_dbc(filename, encoding="utf-8", raw=False):
     """
     Opens a DBC file and return its contents as a pandas
     Dataframe.

tests/test_pyreaddbc.py

@@ -1,4 +1,4 @@
-# import gzip
+import gzip
 import os
 import unittest
 from pathlib import Path
@@ -12,43 +12,40 @@
 path_root = Path(__file__).resolve().parent.parent
 data_files = path_root / "tests/data"
 dbc_file = str(data_files / "STPI2206.dbc")
+temp_dbf_file = str(data_files / "STPI2206.dbf")
+
+dbc_files = [
+    "ZIKABR16.dbc",
+    "STPI2206.dbc",
+    "sids.dbc",
+]
 
 
 class TestDBCChecks(unittest.TestCase):
     def test_read_dbc(self):
         df = read_dbc(dbc_file)
-        self.assertIsInstance(df, pd.DataFrame)
-        self.assertFalse(df.empty)
-        self.assertGreater(len(df.columns), 0)
-        self.assertGreater(len(df), 0)
+        self.assertDataFrameValid(df)
 
     def test_dbc2dbf(self):
-        temp_dbf_file = str(data_files / "STPI2206.dbf")
         dbc2dbf(str(dbc_file), temp_dbf_file)
         self.assertTrue(os.path.isfile(temp_dbf_file))
         df = read_dbc_dbf(temp_dbf_file)
-        self.assertIsInstance(df, pd.DataFrame)
-        self.assertFalse(df.empty)
-        self.assertGreater(len(df.columns), 0)
-        self.assertGreater(len(df), 0)
+        self.assertDataFrameValid(df)
 
     def test_read_dbc_dbf(self):
         df = read_dbc_dbf(dbc_file)
-        self.assertIsInstance(df, pd.DataFrame)
-        self.assertFalse(df.empty)
-        self.assertGreater(len(df.columns), 0)
-        self.assertGreater(len(df), 0)
+        self.assertDataFrameValid(df)
 
     def test_dbf_to_csvgz(self):
         temp_csvgz_file = str(data_files / "STPI2206.csv.gz")
-        dbf_to_csvgz(dbc_file, encoding='iso-8859-1')
+        dbf_to_csvgz(temp_dbf_file, encoding='iso-8859-1')
         self.assertTrue(os.path.isfile(temp_csvgz_file))
-        # with gzip.open(temp_csvgz_file, "rt") as gzfile:
-        #     df = pd.read_csv(gzfile)
-        # assert isinstance(df, pd.DataFrame)
-        # assert not df.empty
-        # assert len(df.columns) > 0
-        # assert len(df) > 0
+        with gzip.open(temp_csvgz_file, "rt") as gzfile:
+            df = pd.read_csv(gzfile)
+        assert isinstance(df, pd.DataFrame)
+        assert not df.empty
+        assert len(df.columns) > 2
+        assert len(df) > 0
 
     @pytest.mark.skipif
     def test_encoding(self):
@@ -66,40 +63,7 @@ def test_encoding(self):
             detected_encoding, common_encodings
         )  # Check if detected encoding is in the list
 
-    def test_dbc_file_size(self):
-        """
-        Test if a DBC file is malformed or truncated.
-        Check if the file size is a multiple of 4 bytes, which is the size of
-        a CAN message in a DBC file. Takes a file path as input and uses the
-        os.path.getsize function to get the file size in bytes.
-        The function then checks if the file size is a multiple of 4 bytes
-        by checking if the remainder of the division of the file size by 4
-        is not zero. If the file size is not a multiple of 4 bytes,
-        the function prints an error message indicating that the file
-        is malformed or truncated and returns False. Otherwise,
-        the function prints a message indicating that the file is
-        a valid DBC file and returns True.
-        """
-        # Get the file size
-        file_size = os.path.getsize(dbc_file)
-
-        # Check if the file size is a multiple of 4 bytes
-        if file_size % 4 != 0:
-            self.fail(f"{dbc_file} is a malformed or truncated DBC file.")
-
-        print(f"{dbc_file} is a valid DBC file.")
-
     def test_dbc_file_header(self):
-        """
-        Reads the first 32 bytes of the file,
-        which contain the file header.
-        The function checks if the header is valid by verifying that
-        it starts with the bytes VJDB and contains a
-        byte sequence of 01 00 00 00 at offset 8. If the header is valid,
-        the function prints a message indicating that the file is
-        a valid DBC file and returns True. Otherwise,
-        it prints an error message and returns False.
-        """
         dbc_file = str(data_files / "STPI2206.dbc")
         with open(dbc_file, 'rb') as dbc_file:
             # Read the first 32 bytes of the file
@@ -117,6 +81,12 @@ def test_dbc_file_header(self):
         print(f"{dbc_file} is a valid DBC file.")
         return True
 
+    def assertDataFrameValid(self, df):
+        self.assertIsInstance(df, pd.DataFrame)
+        self.assertFalse(df.empty)
+        self.assertGreater(len(df.columns), 0)
+        self.assertGreater(len(df), 0)
+
 
 if __name__ == '__main__':
     unittest.main()