Add categories to checks (#109):

This adds categories to each of the checks, though there is no way to enable
or disable checks based off of their category (yet).

docs/categories.md

@@ -0,0 +1,100 @@
+# Categories
+
+Here is a list of the built-in categories in Refurb, and their meanings.
+
+## `builtin`
+
+Checks that have the `builtin` category cover a few different topics:
+
+* Built-in functions such as `print()`, `open()`, `str()`, and so on
+* Statements such as `del`
+* File system related operations such as `open()` and `readlines()`
+
+## `control-flow`
+
+These checks deal with the control flow of a program, such as optimizing usage
+of `return` and `continue`, removing `if` statements under certain conditions,
+and so on.
+
+## `contextlib`
+
+These checks are for the [contextlib](https://docs.python.org/3/library/contextlib.html)
+standard library module.
+
+## `dict`
+
+These checks cover:
+
+* Usage of `dict` objects
+* In some cases, objects supporting the [Mapping](https://docs.python.org/3/library/collections.abc.html#collections.abc.Mapping) protocol
+
+## `fstring`
+
+These checks relate to Python's [f-strings](https://fstring.help/).
+
+## `functools`
+
+These checks relate to the [functools](https://docs.python.org/3/library/functools.html)
+standard library module.
+
+## `iterable`
+
+These checks cover:
+
+* Iterable types such as `list` and `tuple`
+* Standard library objects which are commonly iterated over such as `dict` keys
+
+## `itertools`
+
+These checks relate to the [itertools](https://docs.python.org/3/library/itertools.html)
+standard library module.
+
+## `operator`
+
+These checks relate to the [operator](https://docs.python.org/3/library/operator.html)
+standard library module.
+
+## `logical`
+
+These checks relate to logical cleanups and optimizations, primarily in `if` statements,
+but also in boolean expressions.
+
+## `list`
+
+These checks cover usage of the built-in `list` object.
+
+## `pathlib`
+
+These checks relate to the [pathlib](https://docs.python.org/3/library/pathlib.html)
+standard library module.
+
+## `pythonic`
+
+This is a general catch-all for things which are "unpythonic". It differs from the
+`readability` category because "unreadable" code can still be pythonic.
+
+## `readability`
+
+These checks aim to make existing code more readable. This can be subjective, but in general,
+they reduce the horizontal or vertical length of your code, or make the underlying meaning
+of the code more apparent.
+
+## `scoping`
+
+These checks have to do with Python's scoping rules. For more info on how Python's scoping
+rules work, read [this article](https://realpython.com/python-scope-legb-rule/).
+
+## `string`
+
+These checks deal with usage of [`str`](https://docs.python.org/3/library/stdtypes.html#string-methods)
+objects in Python.
+
+## `set`
+
+These checks deal with usage of [`set`](https://docs.python.org/3/tutorial/datastructures.html#sets)
+objects in Python.
+
+## `truthy`
+
+These checks cover truthy and falsy operations in Python, primarily in the context of `assert` and `if`
+statements.

refurb/checks/builtin/list_extend.py

@@ -42,6 +42,7 @@ class ErrorInfo(Error):
 
     code = 113
     msg: str = "Use `x.extend(...)` instead of repeatedly calling `x.append()`"
+    categories = ["list"]
 
 
 @dataclass

refurb/checks/builtin/no_del.py

@@ -39,6 +39,7 @@ class ErrorInfo(Error):
     """
 
     code = 131
+    categories = ["builtin", "readability"]
 
 
 def check(node: DelStmt, errors: list[Error]) -> None:

refurb/checks/builtin/no_ignored_dict_items.py

@@ -48,6 +48,7 @@ class ErrorInfo(Error):
     """
 
     code = 135
+    categories = ["dict"]
 
 
 def check(

refurb/checks/builtin/print.py

@@ -13,6 +13,7 @@ class ErrorInfo(Error):
 
     code = 105
     msg: str = 'Replace `print("")` with `print()`'
+    categories = ["builtin", "readability"]
 
 
 def check(node: CallExpr, errors: list[Error]) -> None:

refurb/checks/builtin/set_discard.py

@@ -41,6 +41,7 @@ class ErrorInfo(Error):
 
     code = 132
     msg: str = "Replace `if x in s: s.remove(x)` with `s.discard(x)`"
+    categories = ["readability", "set"]
 
 
 def check(node: IfStmt, errors: list[Error]) -> None:

refurb/checks/builtin/use_isinstance_tuple.py

@@ -38,6 +38,7 @@ class ErrorInfo(Error):
     """
 
     code = 121
+    categories = ["readability"]
 
 
 def check(node: OpExpr, errors: list[Error], settings: Settings) -> None:

refurb/checks/builtin/writelines.py

@@ -49,6 +49,7 @@ class ErrorInfo(Error):
 
     code = 122
     msg: str = "Replace `for line in lines: f.write(line)` with `f.writelines(lines)`"  # noqa: E501
+    categories = ["builtin", "readability"]
 
 
 def check(node: WithStmt, errors: list[Error]) -> None:

refurb/checks/contextlib/with_suppress.py

@@ -32,6 +32,7 @@ class ErrorInfo(Error):
     """
 
     code = 107
+    categories = ["contextlib", "readability"]
 
 
 def check(node: TryStmt, errors: list[Error]) -> None:

refurb/checks/flow/no_trailing_continue.py

@@ -61,6 +61,7 @@ def func2(x):
 
     code = 133
     msg: str = "Continue is redundant here"
+    categories = ["control-flow", "readability"]
 
 
 def get_trailing_continue(node: Statement) -> Generator[Statement, None, None]:

refurb/checks/flow/no_trailing_return.py

@@ -56,6 +56,7 @@ def func2(x):
 
     code = 125
     msg: str = "Return is redundant here"
+    categories = ["control-flow", "readability"]
 
 
 def get_trailing_return(node: Statement) -> Generator[Statement, None, None]:

refurb/checks/flow/no_with_assign.py

@@ -41,6 +41,7 @@ class ErrorInfo(Error):
 
     code = 127
     msg: str = "This variable is redeclared later, and can be removed here"
+    categories = ["readability", "scoping"]
 
 
 def check(node: Block | MypyFile, errors: list[Error]) -> None:

refurb/checks/flow/simplify_return.py

@@ -57,6 +57,7 @@ def is_on_axis(position: tuple[int, int]) -> bool:
     """
 
     code = 126
+    categories = ["control-flow", "readability"]
 
 
 def get_trailing_return(node: Statement) -> Statement | None:

refurb/checks/functools/use_cache.py

@@ -35,6 +35,7 @@ def f(x: int) -> int:
 
     code = 134
     msg: str = "Replace `@lru_cache(maxsize=None)` with `@cache`"
+    categories = ["functools", "readability"]
 
 
 def check(node: Decorator, errors: list[Error], settings: Settings) -> None:

refurb/checks/iterable/implicit_readlines.py

@@ -39,6 +39,7 @@ class ErrorInfo(Error):
 
     code = 129
     msg: str = "Replace `f.readlines()` with `f`"
+    categories = ["builtin", "readability"]
 
 
 def get_readline_file_object(expr: Expression) -> NameExpr | None:

refurb/checks/iterable/in_tuple.py

@@ -31,6 +31,7 @@ class ErrorInfo(Error):
     """
 
     code = 109
+    categories = ["iterable", "readability"]
 
 
 def error_msg(oper: str) -> str:

refurb/checks/logical/use_equal_chain.py

@@ -32,6 +32,7 @@ class ErrorInfo(Error):
 
     code = 124
     msg: str = "Replace `x == y and x == z` with `x == y == z`"
+    categories = ["logical", "readability"]
 
 
 def has_common_expr(*exprs: Expression) -> bool:

refurb/checks/logical/use_in.py

@@ -33,6 +33,7 @@ class ErrorInfo(Error):
 
     code = 108
     msg: str = "Replace `x == y or x == z` with `x in (y, z)`"
+    categories = ["logical", "readability"]
 
 
 def check(node: OpExpr, errors: list[Error]) -> None:

refurb/checks/logical/use_or.py

@@ -29,6 +29,7 @@ class ErrorInfo(Error):
 
     code = 110
     msg: str = "Replace `x if x else y` with `x or y`"
+    categories = ["logical", "readability"]
 
 
 def check(node: ConditionalExpr, errors: list[Error]) -> None:

refurb/checks/pathlib/cwd.py

@@ -25,6 +25,7 @@ class ErrorInfo(Error):
 
     code = 104
     msg: str = "Replace `os.getcwd()` with `Path.cwd()`"
+    categories = ["pathlib"]
 
 
 def check(node: CallExpr, errors: list[Error]) -> None:

refurb/checks/pathlib/open.py

@@ -32,6 +32,7 @@ class ErrorInfo(Error):
     """
 
     code = 117
+    categories = ["pathlib"]
 
 
 def check(node: CallExpr, errors: list[Error]) -> None:

refurb/checks/pathlib/read_text.py

@@ -35,6 +35,7 @@ class ErrorInfo(Error):
     """
 
     code = 101
+    categories = ["pathlib"]
 
 
 def check(node: WithStmt, errors: list[Error]) -> None:

refurb/checks/pathlib/with_suffix.py

@@ -36,6 +36,7 @@ class ErrorInfo(Error):
 
     code = 100
     msg: str = "Use `Path(x).with_suffix(y)` instead of slice and concat"  # noqa: E501
+    categories = ["pathlib"]
 
 
 def check(node: OpExpr, errors: list[Error]) -> None:

refurb/checks/pathlib/write_text.py

@@ -34,6 +34,7 @@ class ErrorInfo(Error):
     """
 
     code = 103
+    categories = ["pathlib"]
 
 
 def check(node: WithStmt, errors: list[Error]) -> None:

refurb/checks/readability/in_keys.py

@@ -31,6 +31,7 @@ class ErrorInfo(Error):
     """
 
     code = 130
+    categories = ["dict", "readability"]
 
 
 def check(node: ComparisonExpr, errors: list[Error]) -> None:

refurb/checks/readability/no_double_not.py

@@ -27,6 +27,7 @@ class ErrorInfo(Error):
 
     code = 114
     msg: str = "Replace `not not x` with `bool(x)`"
+    categories = ["builtin", "readability", "truthy"]
 
 
 def check(node: UnaryExpr, errors: list[Error]) -> None:

refurb/checks/readability/no_len_cmp.py

@@ -60,6 +60,7 @@ class ErrorInfo(Error):
     """
 
     code = 115
+    categories = ["iterable", "truthy"]
 
 
 CONTAINER_TYPES = {

refurb/checks/readability/no_unnecessary_cast.py

@@ -53,6 +53,7 @@ class ErrorInfo(Error):
     """
 
     code = 123
+    categories = ["readability"]
 
 
 FUNC_NAMES = {

refurb/checks/readability/use_func_name.py

@@ -39,6 +39,7 @@ class ErrorInfo(Error):
 
     code = 111
     msg: str = "Replace `lambda x: f(x)` with `f`"
+    categories = ["readability"]
 
 
 def get_lambda_arg_names(args: list[Argument]) -> list[str]:

refurb/checks/readability/use_literal.py

@@ -27,6 +27,7 @@ class ErrorInfo(Error):
     """
 
     code = 112
+    categories = ["pythonic", "readability"]
 
 
 FUNC_NAMES = {

refurb/checks/readability/use_operators.py

@@ -44,6 +44,7 @@ class ErrorInfo(Error):
     """
 
     code = 118
+    categories = ["operator"]
 
 
 BINARY_OPERATORS = {

refurb/checks/readability/use_tuple_swap.py

@@ -29,6 +29,7 @@ class ErrorInfo(Error):
 
     code = 128
     msg: str = "Use tuple unpacking instead of temporary variables to swap values"  # noqa: E501
+    categories = ["readability"]
 
 
 def check(node: Block | MypyFile, errors: list[Error]) -> None:

refurb/checks/string/expandtabs.py

@@ -38,6 +38,7 @@ class ErrorInfo(Error):
 
     enabled = False
     code = 106
+    categories = ["string"]
 
 
 def check_str(node: CallExpr, errors: list[Error]) -> None:

refurb/checks/string/fstring_number.py

@@ -27,6 +27,7 @@ class ErrorInfo(Error):
     """
 
     code = 116
+    categories = ["builtin", "fstring"]
 
 
 FUNC_CONVERSIONS = {

refurb/checks/string/startswith.py

@@ -31,6 +31,7 @@ class ErrorInfo(Error):
     """
 
     code = 102
+    categories = ["string"]
 
 
 def check(node: OpExpr, errors: list[Error]) -> None:

refurb/checks/string/use_fstring_fmt.py

@@ -33,6 +33,7 @@ class ErrorInfo(Error):
     """
 
     code = 119
+    categories = ["builtin", "fstring"]
 
 
 CONVERSIONS = {

refurb/error.py

@@ -1,7 +1,7 @@
 from __future__ import annotations
 
 from dataclasses import dataclass
-from typing import ClassVar, Optional
+from typing import ClassVar
 
 
 @dataclass(frozen=True)
@@ -25,7 +25,8 @@ class Error:
     line: int
     column: int
     msg: str
-    filename: Optional[str] = None
+    filename: str | None = None
+    categories: list[str] | None = None
 
     def __str__(self) -> str:
         return f"{self.filename}:{self.line}:{self.column + 1} [{self.prefix}{self.code}]: {self.msg}"  # noqa: E501