Spruce up docs for slice-to-remove-prefix-or-suffix (FURB188)

Author: AlexWaygood

crates/ruff_linter/src/rules/refurb/rules/slice_to_remove_prefix_or_suffix.rs

@@ -8,32 +8,34 @@ use crate::Locator;
 use crate::{checkers::ast::Checker, settings::types::PythonVersion};
 
 /// ## What it does
-/// Checks for the removal of a prefix or suffix from a string by assigning
-/// the string to a slice after checking `.startswith()` or `.endswith()`, respectively.
+/// Checks for code that could be written more idiomatically using
+/// [`str.removeprefix()`](https://docs.python.org/3/library/stdtypes.html#str.removeprefix)
+/// or [`str.removesuffix()`](https://docs.python.org/3/library/stdtypes.html#str.removesuffix).
+///
+/// Specifically, the rule flags code that conditionally removes a prefix or suffix
+/// using a slice operation following an `if` test that uses `str.startswith()` or `str.endswith()`.
+///
+/// The rule is only applied if your project targets Python 3.9 or later.
 ///
 /// ## Why is this bad?
-/// The methods [`str.removeprefix`](https://docs.python.org/3/library/stdtypes.html#str.removeprefix)
-/// and [`str.removesuffix`](https://docs.python.org/3/library/stdtypes.html#str.removesuffix),
-/// introduced in Python 3.9, have the same behavior
-/// and are more readable and efficient.
+/// The methods [`str.removeprefix()`](https://docs.python.org/3/library/stdtypes.html#str.removeprefix)
+/// and [`str.removesuffix()`](https://docs.python.org/3/library/stdtypes.html#str.removesuffix),
+/// introduced in Python 3.9, have the same behavior while being more readable and efficient.
 ///
 /// ## Example
 /// ```python
-/// filename[:-4] if filename.endswith(".txt") else filename
-/// ```
+/// def example(filename: str, text: str):
+///     filename = filename[:-4] if filename.endswith(".txt") else filename
 ///
-/// ```python
-/// if text.startswith("pre"):
-///     text = text[3:]
+///     if text.startswith("pre"):
+///         text = text[3:]
 /// ```
 ///
 /// Use instead:
 /// ```python
-/// filename = filename.removesuffix(".txt")
-/// ```
-///
-/// ```python
-/// text = text.removeprefix("pre")
+/// def example(filename: str, text: str):
+///     filename = filename.removesuffix(".txt")
+///     text = text.removeprefix("pre")
 /// ```
 #[derive(ViolationMetadata)]
 pub(crate) struct SliceToRemovePrefixOrSuffix {
@@ -46,10 +48,10 @@ impl AlwaysFixableViolation for SliceToRemovePrefixOrSuffix {
     fn message(&self) -> String {
         match self.affix_kind {
             AffixKind::StartsWith => {
-                "Prefer `removeprefix` over conditionally replacing with slice.".to_string()
+                "Prefer `str.removeprefix()` over conditionally replacing with slice.".to_string()
             }
             AffixKind::EndsWith => {
-                "Prefer `removesuffix` over conditionally replacing with slice.".to_string()
+                "Prefer `str.removesuffix()` over conditionally replacing with slice.".to_string()
             }
         }
     }

crates/ruff_linter/src/rules/refurb/snapshots/ruff_linter__rules__refurb__tests__FURB188_FURB188.py.snap

@@ -1,8 +1,7 @@
 ---
 source: crates/ruff_linter/src/rules/refurb/mod.rs
-snapshot_kind: text
 ---
-FURB188.py:7:5: FURB188 [*] Prefer `removesuffix` over conditionally replacing with slice.
+FURB188.py:7:5: FURB188 [*] Prefer `str.removesuffix()` over conditionally replacing with slice.
    |
  6 |   def remove_extension_via_slice(filename: str) -> str:
  7 |       if filename.endswith(".txt"):
@@ -25,7 +24,7 @@ FURB188.py:7:5: FURB188 [*] Prefer `removesuffix` over conditionally replacing w
 10 9 |     return filename
 11 10 | 
 
-FURB188.py:14:5: FURB188 [*] Prefer `removesuffix` over conditionally replacing with slice.
+FURB188.py:14:5: FURB188 [*] Prefer `str.removesuffix()` over conditionally replacing with slice.
    |
 13 |   def remove_extension_via_slice_len(filename: str, extension: str) -> str:
 14 |       if filename.endswith(extension):
@@ -48,7 +47,7 @@ FURB188.py:14:5: FURB188 [*] Prefer `removesuffix` over conditionally replacing
 17 16 |     return filename
 18 17 | 
 
-FURB188.py:21:12: FURB188 [*] Prefer `removesuffix` over conditionally replacing with slice.
+FURB188.py:21:12: FURB188 [*] Prefer `str.removesuffix()` over conditionally replacing with slice.
    |
 20 | def remove_extension_via_ternary(filename: str) -> str:
 21 |     return filename[:-4] if filename.endswith(".txt") else filename
@@ -66,7 +65,7 @@ FURB188.py:21:12: FURB188 [*] Prefer `removesuffix` over conditionally replacing
 23 23 | 
 24 24 | def remove_extension_via_ternary_with_len(filename: str, extension: str) -> str:
 
-FURB188.py:25:12: FURB188 [*] Prefer `removesuffix` over conditionally replacing with slice.
+FURB188.py:25:12: FURB188 [*] Prefer `str.removesuffix()` over conditionally replacing with slice.
    |
 24 | def remove_extension_via_ternary_with_len(filename: str, extension: str) -> str:
 25 |     return filename[:-len(extension)] if filename.endswith(extension) else filename
@@ -84,7 +83,7 @@ FURB188.py:25:12: FURB188 [*] Prefer `removesuffix` over conditionally replacing
 27 27 | 
 28 28 | def remove_prefix(filename: str) -> str:
 
-FURB188.py:29:12: FURB188 [*] Prefer `removeprefix` over conditionally replacing with slice.
+FURB188.py:29:12: FURB188 [*] Prefer `str.removeprefix()` over conditionally replacing with slice.
    |
 28 | def remove_prefix(filename: str) -> str:
 29 |     return filename[4:] if filename.startswith("abc-") else filename
@@ -102,7 +101,7 @@ FURB188.py:29:12: FURB188 [*] Prefer `removeprefix` over conditionally replacing
 31 31 | 
 32 32 | def remove_prefix_via_len(filename: str, prefix: str) -> str:
 
-FURB188.py:33:12: FURB188 [*] Prefer `removeprefix` over conditionally replacing with slice.
+FURB188.py:33:12: FURB188 [*] Prefer `str.removeprefix()` over conditionally replacing with slice.
    |
 32 | def remove_prefix_via_len(filename: str, prefix: str) -> str:
 33 |     return filename[len(prefix):] if filename.startswith(prefix) else filename
@@ -120,7 +119,7 @@ FURB188.py:33:12: FURB188 [*] Prefer `removeprefix` over conditionally replacing
 35 35 | 
 36 36 | # these should not
 
-FURB188.py:146:9: FURB188 [*] Prefer `removesuffix` over conditionally replacing with slice.
+FURB188.py:146:9: FURB188 [*] Prefer `str.removesuffix()` over conditionally replacing with slice.
     |
 144 |     SUFFIX = "suffix"
 145 | 
@@ -141,7 +140,7 @@ FURB188.py:146:9: FURB188 [*] Prefer `removesuffix` over conditionally replacing
 148 148 | def remove_prefix_comparable_literal_expr() -> None:
 149 149 |     return ("abc" "def")[3:] if ("abc" "def").startswith("abc") else "abc" "def"
 
-FURB188.py:149:12: FURB188 [*] Prefer `removeprefix` over conditionally replacing with slice.
+FURB188.py:149:12: FURB188 [*] Prefer `str.removeprefix()` over conditionally replacing with slice.
     |
 148 | def remove_prefix_comparable_literal_expr() -> None:
 149 |     return ("abc" "def")[3:] if ("abc" "def").startswith("abc") else "abc" "def"
@@ -161,7 +160,7 @@ FURB188.py:149:12: FURB188 [*] Prefer `removeprefix` over conditionally replacin
 151 151 | def shadow_builtins(filename: str, extension: str) -> None:
 152 152 |     from builtins import len as builtins_len
 
-FURB188.py:154:12: FURB188 [*] Prefer `removesuffix` over conditionally replacing with slice.
+FURB188.py:154:12: FURB188 [*] Prefer `str.removesuffix()` over conditionally replacing with slice.
     |
 152 |     from builtins import len as builtins_len
 153 | 
@@ -182,7 +181,7 @@ FURB188.py:154:12: FURB188 [*] Prefer `removesuffix` over conditionally replacin
 156 156 | def okay_steps():
 157 157 |     text = "!x!y!z"
 
-FURB188.py:158:5: FURB188 [*] Prefer `removeprefix` over conditionally replacing with slice.
+FURB188.py:158:5: FURB188 [*] Prefer `str.removeprefix()` over conditionally replacing with slice.
     |
 156 |   def okay_steps():
 157 |       text = "!x!y!z"
@@ -206,7 +205,7 @@ FURB188.py:158:5: FURB188 [*] Prefer `removeprefix` over conditionally replacing
 161 160 |         text = text[1::True]
 162 161 |     if text.startswith("!"):
 
-FURB188.py:160:5: FURB188 [*] Prefer `removeprefix` over conditionally replacing with slice.
+FURB188.py:160:5: FURB188 [*] Prefer `str.removeprefix()` over conditionally replacing with slice.
     |
 158 |       if text.startswith("!"):
 159 |           text = text[1::1]
@@ -230,7 +229,7 @@ FURB188.py:160:5: FURB188 [*] Prefer `removeprefix` over conditionally replacing
 163 162 |         text = text[1::None]
 164 163 |     print(text)
 
-FURB188.py:162:5: FURB188 [*] Prefer `removeprefix` over conditionally replacing with slice.
+FURB188.py:162:5: FURB188 [*] Prefer `str.removeprefix()` over conditionally replacing with slice.
     |
 160 |       if text.startswith("!"):
 161 |           text = text[1::True]
@@ -253,7 +252,7 @@ FURB188.py:162:5: FURB188 [*] Prefer `removeprefix` over conditionally replacing
 165 164 | 
 166 165 | 
 
-FURB188.py:183:5: FURB188 [*] Prefer `removeprefix` over conditionally replacing with slice.
+FURB188.py:183:5: FURB188 [*] Prefer `str.removeprefix()` over conditionally replacing with slice.
     |
 181 |       # with fix `text = text.removeprefix("ř")`
 182 |       text = "řetězec"
@@ -275,7 +274,7 @@ FURB188.py:183:5: FURB188 [*] Prefer `removeprefix` over conditionally replacing
 186 185 | 
 187 186 | def handle_surrogates():
 
-FURB188.py:190:5: FURB188 [*] Prefer `removeprefix` over conditionally replacing with slice.
+FURB188.py:190:5: FURB188 [*] Prefer `str.removeprefix()` over conditionally replacing with slice.
     |
 188 |       # should be linted
 189 |       text = "\ud800\udc00heythere"
@@ -299,7 +298,7 @@ FURB188.py:190:5: FURB188 [*] Prefer `removeprefix` over conditionally replacing
 193 192 |     if text.startswith("\U00010000"):
 194 193 |         text = text[1:]
 
-FURB188.py:193:5: FURB188 [*] Prefer `removeprefix` over conditionally replacing with slice.
+FURB188.py:193:5: FURB188 [*] Prefer `str.removeprefix()` over conditionally replacing with slice.
     |
 191 |           text = text[2:]
 192 |       text = "\U00010000heythere"