Flake8 maintenance: test_encodings.py (#557)

- remove pytest.mark.skip from 2 tests that now pass
- remove unused imports
- change lamda statements to functions
- add asserts to act on the formerly unused variables.

tests/test_encoding.py

@@ -1,18 +1,18 @@
-import os, sys
+import os
 
-sys.path.insert(0, os.path.dirname(os.path.dirname(__file__)))
-import logging
+from pathlib import Path
 
-import codecs
+from lasio import read, reader
 
-import pytest
 
-from pathlib import Path
+def egfn(fn):
+    # egfn = lambda fn: os.path.join(os.path.dirname(__file__), "examples", fn)
+    return os.path.join(os.path.dirname(__file__), "examples", fn)
 
-from lasio import read, reader
 
-egfn = lambda fn: os.path.join(os.path.dirname(__file__), "examples", fn)
-stegfn = lambda vers, fn: os.path.join(os.path.dirname(__file__), "examples", vers, fn)
+def stegfn(vers, fn):
+    # stegfn = lambda vers, fn: os.path.join(os.path.dirname(__file__), "examples", vers, fn)
+    return os.path.join(os.path.dirname(__file__), "examples", vers, fn)
 
 
 def test_encoding_attr():
@@ -22,36 +22,48 @@ def test_encoding_attr():
 
 def test_utf8_chardet():
     las = read(egfn("encodings_utf8.las"), autodetect_encoding="chardet")
+    assert las.encoding.upper() == "UTF-8"
 
 
 def test_utf8wbom_chardet():
     las = read(egfn("encodings_utf8wbom.las"), autodetect_encoding="chardet")
+    # "SIG" is short for signature. This means it will use the BOM metadata
+    # instead of the file contents to identify the encoding
+    assert las.encoding.upper() == "UTF-8-SIG"
 
 
 def test_utf16lebom_chardet():
+    # BE = Big Endian. Big Endian is the default endian.
     las = read(egfn("encodings_utf16lebom.las"), autodetect_encoding="chardet")
+    assert las.encoding.upper() == "UTF-16"
 
 
 def test_utf16le_specified_ok():
+    # LE = Little Endian
     las = read(egfn("encodings_utf16le.las"), encoding="UTF-16-LE")
+    assert las.encoding.upper() == "UTF-16-LE"
 
 
-@pytest.mark.skip(reason="this is not behaving properly see PR #326")
-def test_utf16le_chardet_fails():
-    with pytest.raises(Exception):
-        las = read(egfn("encodings_utf16le.las"), autodetect_encoding="chardet")
+def test_utf16le_chardet():
+    # 02-15-2023: chardet is correctly identifying this file now, chardet: 5.1.0.
+    las = read(egfn("encodings_utf16le.las"), autodetect_encoding="chardet")
+    assert las.encoding.upper() == "UTF-16LE"
 
 
 def test_utf16bebom_chardet():
     las = read(egfn("encodings_utf16bebom.las"), autodetect_encoding="chardet")
+    assert las.encoding.upper() == "UTF-16"
 
 
 def test_iso88591_chardet():
     las = read(egfn("encodings_iso88591.las"), autodetect_encoding="chardet")
+    assert las.encoding.upper() == "ISO-8859-1"
 
 
 def test_cp1252_chardet():
+    #  Chardet read the file as ISO-8859-1
     las = read(egfn("encodings_cp1252.las"), autodetect_encoding="chardet")
+    assert las.encoding.upper() == "ISO-8859-1"
 
 
 """
@@ -61,48 +73,55 @@ def test_cp1252_chardet():
 
 def test_pathlib_utf8_chardet():
     las = read(Path(egfn("encodings_utf8.las")), autodetect_encoding="chardet")
+    assert las.encoding.upper() == "UTF-8"
 
 
 def test_pathlib_utf8wbom_chardet():
     las = read(Path(egfn("encodings_utf8wbom.las")), autodetect_encoding="chardet")
+    assert las.encoding.upper() == "UTF-8-SIG"
 
 
 def test_pathlib_utf16lebom_chardet():
     las = read(Path(egfn("encodings_utf16lebom.las")), autodetect_encoding="chardet")
+    assert las.encoding.upper() == "UTF-16"
 
 
 def test_pathlib_utf16le_specified_ok():
     las = read(Path(egfn("encodings_utf16le.las")), encoding="UTF-16-LE")
+    assert las.encoding.upper() == "UTF-16-LE"
 
 
-@pytest.mark.skip(reason="this is not behaving properly see PR #326")
-def test_pathlib_utf16le_chardet_fails():
-    with pytest.raises(Exception):
-        las = read(Path(egfn("encodings_utf16le.las")), autodetect_encoding="chardet")
+def test_pathlib_utf16le_chardet():
+    # 02-15-2023: chardet is correctly identifying this file now, chardet: 5.1.0.
+    las = read(Path(egfn("encodings_utf16le.las")), autodetect_encoding="chardet")
+    assert las.encoding.upper() == "UTF-16LE"
 
 
 def test_pathlib_utf16bebom_chardet():
     las = read(Path(egfn("encodings_utf16bebom.las")), autodetect_encoding="chardet")
+    assert las.encoding.upper() == "UTF-16"
 
 
 def test_pathlib_iso88591_chardet():
     las = read(Path(egfn("encodings_iso88591.las")), autodetect_encoding="chardet")
+    assert las.encoding.upper() == "ISO-8859-1"
 
 
 def test_pathlib_cp1252_chardet():
     las = read(Path(egfn("encodings_cp1252.las")), autodetect_encoding="chardet")
+    assert las.encoding.upper() == "ISO-8859-1"
 
 
 def test_adhoc_test_encoding():
     filename = stegfn("1.2", "sample.las")
-    res = reader.adhoc_test_encoding(filename)
-    assert res == "ascii"
+    encoding = reader.adhoc_test_encoding(filename)
+    assert encoding.upper() == "ASCII"
 
 
 def test_open_with_codecs_no_autodetect():
     filename = stegfn("1.2", "sample.las")
     obj, encoding = reader.open_with_codecs(filename, autodetect_encoding=False)
-    assert encoding == "ascii"
+    assert encoding.upper() == "ASCII"
 
 
 def test_open_with_codecs_no_autodetect_chars():