Fix most pylint warnings, add main()s

Move all CLI script code under `if __name__ == "__main__"` to separate
module-level `main()` methods that serve as the entrypoint. This fixes
many invalid-name errors and all redefined-outer-name errors.

Sort imports alphabetically, and group them in the order:
builtins, 3rd-parties, local stuff. This eliminates import-related
warnings.

Other minor warnings are dealt with by fixing the code, or disabling the
warning if it is a false positive.

Notably, refactor warnings (Rxxxx) are not handled. These require
considerably more thought to work out. Since VS code doesn't show them
as errors, we're in no rush.

Unrelated to Pylint warnings: In sample scripts, remove the statements
that directly added the project root to sys.path. This was a hack used
to make d2txt.py importable in sample scripts. Now that we have
`pip install -e .`, there's no need to tamper with sys.path.

Note: As of Pylint 2.4.4, it incorrectly believes that all module-level
variables are constants, and emits invalid-name on them. This check had
to be disabled via comments sprinkled throughout the codebase.
Looks like this will be fixed in Pylint 2.5.0, though. It's already been
integrated into the main branch:
pylint-dev/pylint@3422e4a

Also see relevant issues that motivated the change:
- pylint-dev/pylint#3111
- pylint-dev/pylint#3132

The latest changelog with the fix mentioned under 2.5.0 changes:
https://github.com/PyCQA/pylint/blob/f2f4e6f42416644471ab003d4df7ecf052c3c411/ChangeLog

d2txt.py

@@ -5,6 +5,7 @@
 import collections.abc
 import csv
 from itertools import islice
+import sys
 from typing import Any
 from typing import List
 from typing import Tuple
@@ -429,7 +430,8 @@ def toml_to_d2txt(toml_data: str) -> D2TXT:
     return d2txt_data
 
 
-if __name__ == "__main__":
+def main(argv: List[str]) -> None:
+    """Entrypoint of the command line script."""
     arg_parser = ArgumentParser()
     arg_subparsers = arg_parser.add_subparsers(dest="command")
 
@@ -445,7 +447,7 @@ def toml_to_d2txt(toml_data: str) -> D2TXT:
     arg_parser_decompile.add_argument("txtfile", help="TXT file to read from")
     arg_parser_decompile.add_argument("tomlfile", help="TOML file to write to")
 
-    args = arg_parser.parse_args()
+    args = arg_parser.parse_args(argv)
 
     if args.command is None:
         arg_parser.print_help()
@@ -460,3 +462,6 @@ def toml_to_d2txt(toml_data: str) -> D2TXT:
     else:
         raise RuntimeError(f"Unexpected command: {args.command!r}")
 
+
+if __name__ == "__main__":
+    main(sys.argv[1:])

samples/add_skpoint_restrictions.py

@@ -10,11 +10,8 @@
 Note: This script modifies Skills.txt.
 """
 
-
+import argparse
 import sys
-from os import path
-
-sys.path.insert(0, path.abspath(path.join(path.dirname(__file__), "..")))
 
 from d2txt import D2TXT
 
@@ -64,9 +61,8 @@ def combine_skpoints_check_formula(formulas):
     return f"({formulas}) ? 1 : 999"
 
 
-if __name__ == "__main__":
-    import argparse
-
+def main(argv):
+    """Entrypoint of the command line script."""
     arg_parser = argparse.ArgumentParser(description=__doc__)
     arg_parser.add_argument("skills_txt", help="Path to Skills.txt")
     arg_parser.add_argument(
@@ -85,7 +81,7 @@ def combine_skpoints_check_formula(formulas):
         help="If provided, specifies minimum blvl of all reqskills as a requirement",
     )
 
-    args = arg_parser.parse_args()
+    args = arg_parser.parse_args(argv)
 
     skills_txt = D2TXT.load_txt(args.skills_txt)
     num_skills_updated = 0
@@ -114,3 +110,6 @@ def combine_skpoints_check_formula(formulas):
     skills_txt.to_txt(args.skills_txt)
     print(f"{num_skills_updated} skill(s) updated in {args.skills_txt}")
 
+
+if __name__ == "__main__":
+    main(sys.argv[1:])

samples/group_weapons_by_hand.py

@@ -6,11 +6,8 @@
 Note: This script modifies Weapons.txt.
 """
 
-
+import argparse
 import sys
-from os import path
-
-sys.path.insert(0, path.abspath(path.join(path.dirname(__file__), "..")))
 
 from d2txt import D2TXT
 
@@ -35,9 +32,8 @@ def check_item_code(item_code):
     return item_code
 
 
-if __name__ == "__main__":
-    import argparse
-
+def main(argv):
+    """Entrypoint of the command line script."""
     arg_parser = argparse.ArgumentParser(description=__doc__)
 
     arg_parser.add_argument("weapons_txt", help="Path to Weapons.txt")
@@ -57,7 +53,7 @@ def check_item_code(item_code):
         help="If provided, item code to assign to 1-or-2-hand weapons",
     )
 
-    args = vars(arg_parser.parse_args())
+    args = vars(arg_parser.parse_args(argv))
 
     weapons_txt = D2TXT.load_txt(args["weapons_txt"])
 
@@ -69,7 +65,8 @@ def check_item_code(item_code):
 
         if weapon["type2"]:
             print(
-                f'Warning: Row {row_index + 1} is skipped -- {weapon["name"]} already has \'type2\' assigned.'
+                f"Warning: Row {row_index + 1} is skipped -- "
+                f'{weapon["name"]} already has \'type2\' assigned.'
             )
             continue
 
@@ -97,3 +94,6 @@ def check_item_code(item_code):
             f'\'{args["both"]}\' has been assigned to {num_both} 1-or-2-hand weapon(s)'
         )
 
+
+if __name__ == "__main__":
+    main(sys.argv[1:])

samples/itype_analyzer.py

@@ -2,18 +2,16 @@
 
 """Reads ItemTypes.txt, Weapons.txt and prints graphs of the item type hierarchy."""
 
-
-import colorama
+import argparse
 import sys
-from os import path
 
-sys.path.insert(0, path.abspath(path.join(path.dirname(__file__), "..")))
+import colorama
+from colorama import Fore
 
 from d2txt import D2TXT
 
 
 colorama.init()
-Fore = colorama.Fore
 
 
 class ITypeNode:
@@ -129,14 +127,13 @@ def print_itype_tree(node, one_handers=None, two_handers=None, current_depth=0):
         print_itype_tree(child, one_handers, two_handers, current_depth + 1)
 
 
-if __name__ == "__main__":
-    import argparse
-
+def main(argv):
+    """Entrypoint of the command line script."""
     arg_parser = argparse.ArgumentParser(__doc__)
     arg_parser.add_argument("itemtypes_txt", help="Path to ItemTypes.txt")
     arg_parser.add_argument("weapons_txt", help="Path to Weapons.txt")
 
-    args = arg_parser.parse_args()
+    args = arg_parser.parse_args(argv)
 
     item_types_txt = D2TXT.load_txt(args.itemtypes_txt)
     weapons_txt = D2TXT.load_txt(args.weapons_txt)
@@ -154,3 +151,7 @@ def print_itype_tree(node, one_handers=None, two_handers=None, current_depth=0):
     for node in itype_nodes.values():
         if not node.parents:
             print_itype_tree(node, one_handers=one_handers, two_handers=two_handers)
+
+
+if __name__ == "__main__":
+    main(sys.argv[1:])

samples/rebalance-degrading-tc.py → samples/rebalance_degrading_tc.py

@@ -11,41 +11,38 @@
 Note: This script modifies TreasureClassEx.txt.
 """
 
-
+import argparse
+import re
 import sys
-from os import path
-
-sys.path.insert(0, path.abspath(path.join(path.dirname(__file__), "..")))
 
 from d2txt import D2TXT
-import re
 
 
 class DuplicateKeyError(Exception):
-    pass
+    "Error raised when a duplicate key is found."
 
 
 def make_tc_dict(tcex_txt):
     """Returns a dictionary of rows in TreasureClassEx.txt keyed by name."""
     tc_dict = {}
-    for tc in tcex_txt:
-        name = tc["Treasure Class"]
+    for tc_entry in tcex_txt:
+        name = tc_entry["Treasure Class"]
         if name in tc_dict:
             raise DuplicateKeyError(name)
-        tc_dict[name] = tc
+        tc_dict[name] = tc_entry
     return tc_dict
 
 
 TC_PROB_COLUMNS = {f"Item{i}": f"Prob{i}" for i in range(1, 11)}
 
 
-def sum_probs(tc):
+def sum_probs(tc_entry):
     """Returns the sum of all `ProbN` fields in the given treasureclass row."""
     total_probs = 0
     for item_col, prob_col in TC_PROB_COLUMNS.items():
-        if not tc[item_col]:
+        if not tc_entry[item_col]:
             continue
-        total_probs += int(tc[prob_col])
+        total_probs += int(tc_entry[prob_col])
     return total_probs
 
 
@@ -54,9 +51,8 @@ def match_in_patterns(text, patterns):
     return any(pattern.search(text) for pattern in patterns)
 
 
-if __name__ == "__main__":
-    import argparse
-
+def main(argv):
+    """Entrypoint of the command line script."""
     arg_parser = argparse.ArgumentParser(description=__doc__)
     arg_parser.add_argument("tcex_txt", help="Path to TreasureClassEx.txt")
     arg_parser.add_argument(
@@ -66,7 +62,7 @@ def match_in_patterns(text, patterns):
         "-i", "--ignore-case", action="store_true", help="Use case-insensitive matching"
     )
 
-    args = arg_parser.parse_args()
+    args = arg_parser.parse_args(argv)
 
     tcex_txt = D2TXT.load_txt(args.tcex_txt)
     tc_dict = make_tc_dict(tcex_txt)
@@ -82,8 +78,8 @@ def match_in_patterns(text, patterns):
 
     num_matched_tcs = 0
     num_rebalanced_tcs = 0
-    for tc in tcex_txt:
-        name = tc["Treasure Class"]
+    for tc_entry in tcex_txt:
+        name = tc_entry["Treasure Class"]
         if not match_in_patterns(name, tc_patterns):
             continue
 
@@ -93,15 +89,19 @@ def match_in_patterns(text, patterns):
         # can only refer to other TCs above its row, we assume that all previous
         # TCs have already been rebalanced.
         for item_col, prob_col in TC_PROB_COLUMNS.items():
-            item_name = tc[item_col]
+            item_name = tc_entry[item_col]
             if not item_name:
                 continue
             if item_name in tc_dict and match_in_patterns(item_name, tc_patterns):
-                tc[prob_col] = sum_probs(tc_dict[item_name])
+                tc_entry[prob_col] = sum_probs(tc_dict[item_name])
                 num_rebalanced_tcs += 1
 
     tcex_txt.to_txt(args.tcex_txt)
     print(
-        f"{num_matched_tcs} treasureclass(es) matched, {num_rebalanced_tcs} treasureclass(es) rebalanced."
+        f"{num_matched_tcs} treasureclass(es) matched, "
+        f"{num_rebalanced_tcs} treasureclass(es) rebalanced."
     )
 
+
+if __name__ == "__main__":
+    main(sys.argv[1:])

setup.py

@@ -4,7 +4,7 @@
 
 
 with open("README.md", "r") as readme_md:
-    readme = readme_md.read()
+    readme = readme_md.read()  # pylint: disable=invalid-name
 
 setuptools.setup(
     name="d2txt",

tests/test_d2txt.py

@@ -47,7 +47,7 @@ def test_empty_txt(self):
         d2txt = D2TXT([])
         self.assertEqual(len(d2txt), 0)
         with self.assertRaises(IndexError):
-            d2txt[0]
+            d2txt[0]  # pylint:disable=pointless-statement
         with self.assertRaises(IndexError):
             d2txt[0] = []
 
@@ -93,15 +93,15 @@ def test_invalid_row_and_cell(self):
         d2txt.append(["one", "two", "six"])
 
         with self.assertRaises(IndexError):
-            d2txt[99]
+            d2txt[99]  # pylint:disable=pointless-statement
         with self.assertRaises(IndexError):
             d2txt[99] = ["mangy", "dog", "cow"]
         with self.assertRaises(IndexError):
-            d2txt[99]["column 1"]
+            d2txt[99]["column 1"]  # pylint:disable=pointless-statement
         with self.assertRaises(IndexError):
             d2txt[99]["column 1"] = "cat"
         with self.assertRaises(KeyError):
-            d2txt[0]["column 99"]
+            d2txt[0]["column 99"]  # pylint:disable=pointless-statement
         with self.assertRaises(KeyError):
             d2txt[0]["column 99"] = "bird"
 
@@ -114,7 +114,7 @@ def test_column_name_case_sensitivity(self):
             list(d2txt[0].values()), ["lowercase", "capital letters", "uppercase"],
         )
         with self.assertRaises(KeyError):
-            d2txt[0]["column NAME"]
+            d2txt[0]["column NAME"]  # pylint:disable=pointless-statement
 
         d2txt[0]["COLUMN NAME"] = "c"
         d2txt[0]["Column Name"] = "b"
@@ -589,4 +589,3 @@ def test_surrounding_quotes(self):
             "'single quotes'\t\"double quotes\"\t`backticks`\r\n"
             "'single quotes'\t\"double quotes\"\t`backticks`\r\n",
         )
-

tests/test_toml.py

@@ -2,7 +2,6 @@
 """Unit test for conversion to and from TOML."""
 
 import os
-from os import path
 from tempfile import NamedTemporaryFile
 import unittest
 
@@ -92,12 +91,17 @@ def test_bitfield_decode(self):
         d2txt = D2TXT(["aurafilter"])
         d2txt.extend([["33025"], ["0"], ["65535"], ["4294901760"]])
 
-        self.maxDiff = None
+        self.maxDiff = None  # pylint: disable=invalid-name
         self.assertEqual(
             d2txt_to_toml(d2txt),
             "columns = [\n  'aurafilter',\n]\n\n"
             "[[rows]]\naurafilter = [['FindPlayers', 'NotInsideTowns', 'IgnoreAllies']]\n\n"
             "[[rows]]\naurafilter = [[]]\n\n"
-            "[[rows]]\naurafilter = [['FindPlayers', 'FindMonsters', 'FindOnlyUndead', 'FindMissiles', 'FindObjects', 'FindItems', 'FindAttackable', 'NotInsideTowns', 'UseLineOfSight', 'FindSelectable', 'FindCorpses', 'NotInsideTowns2', 'IgnoreBoss', 'IgnoreAllies'], [0x840]]\n\n"
-            "[[rows]]\naurafilter = [['IgnoreNPC', 'IgnorePrimeEvil', 'IgnoreJustHitUnits'], [0xFFF20000]]\n\n",
+            "[[rows]]\naurafilter = "
+            "[['FindPlayers', 'FindMonsters', 'FindOnlyUndead', 'FindMissiles', "
+            "'FindObjects', 'FindItems', 'FindAttackable', 'NotInsideTowns', "
+            "'UseLineOfSight', 'FindSelectable', 'FindCorpses', 'NotInsideTowns2', "
+            "'IgnoreBoss', 'IgnoreAllies'], [0x840]]\n\n"
+            "[[rows]]\naurafilter = "
+            "[['IgnoreNPC', 'IgnorePrimeEvil', 'IgnoreJustHitUnits'], [0xFFF20000]]\n\n",
         )