Simplify and code review update

crates/ruff/resources/test/fixtures/pycodestyle/W605_2.py

@@ -44,8 +44,11 @@
 value = f'\{{1}}'
 value = f'\{1}'
 value = f'{1:\}'
+value = f"{f"\{1}"}"
+value = rf"{f"\{1}"}"
 
 # Okay
 value = rf'\{{1}}'
 value = rf'\{1}'
 value = rf'{1:\}'
+value = f"{rf"\{1}"}"

crates/ruff/src/rules/pycodestyle/rules/invalid_escape_sequence.rs

@@ -47,36 +47,22 @@ pub(crate) fn invalid_escape_sequence(
  diagnostics: &mut Vec<Diagnostic>,
  locator: &Locator,
  indexer: &Indexer,
- tok: &Tok,
- tok_range: TextRange,
+ token: &Tok,
+ token_range: TextRange,
  autofix: bool,
 ) {
- let (start_offset, body) = match tok {
+ let token_source_code = match token {
  Tok::FStringMiddle { value, is_raw } => {
  if *is_raw {
  return;
  }
- (tok_range.start(), value.as_str())
+ value.as_str()
  }
- Tok::String {
- value,
- kind,
- triple_quoted,
- } => {
+ Tok::String { kind, .. } => {
  if kind.is_raw() {
  return;
  }
-
- let quote_len = if *triple_quoted {
- TextSize::new(3)
- } else {
- TextSize::new(1)
- };
-
- (
- tok_range.start() + kind.prefix_len() + quote_len,
- value.as_str(),
- )
+ locator.slice(token_range)
  }
  _ => return,
  };
@@ -85,7 +71,7 @@ pub(crate) fn invalid_escape_sequence(
  let mut invalid_escape_sequence = Vec::new();
 
  let mut prev = None;
- let bytes = body.as_bytes();
+ let bytes = token_source_code.as_bytes();
  for i in memchr_iter(b'\\', bytes) {
  // If the previous character was also a backslash, skip.
  if prev.is_some_and(|prev| prev == i - 1) {
@@ -95,18 +81,18 @@ pub(crate) fn invalid_escape_sequence(
 
  prev = Some(i);
 
- let next_char = match body[i + 1..].chars().next() {
+ let next_char = match token_source_code[i + 1..].chars().next() {
  Some(next_char) => next_char,
- None if tok.is_f_string_middle() => {
+ None if token.is_f_string_middle() => {
  // If we're at the end of a f-string middle token, the next character
  // is actually emitted as a different token. For example,
  //
  // ```python
  // f"\{1}"
  // ```
  //
- // is lexed as `FStringMiddle('\\')` and `LBrace`, so we need to check
- // the next character in the source file.
+ // is lexed as `FStringMiddle('\\')` and `LBrace` (ignoring irrelevant
+ // tokens), so we need to check the next character in the source code.
  //
  // Now, if we're at the end of the f-string itself, the lexer wouldn't
  // have emitted the `FStringMiddle` token in the first place. For example,
@@ -116,11 +102,14 @@ pub(crate) fn invalid_escape_sequence(
  // ```
  //
  // Here, there won't be any `FStringMiddle` because it's an unterminated
- // f-string.
- let Some(next_char) = locator.after(tok_range.end()).chars().next() else {
+ // f-string. This means that if there's a `FStringMiddle` token and we
+ // encounter a `\` character, then the next character is always going to
+ // be part of the f-string.
+ if let Some(next_char) = locator.after(token_range.end()).chars().next() {
+ next_char
+ } else {
  continue;
- };
- next_char
+ }
  }
  // If we're at the end of the file, skip.
  None => continue,
@@ -164,7 +153,7 @@ pub(crate) fn invalid_escape_sequence(
  continue;
  }
 
- let location = start_offset + TextSize::try_from(i).unwrap();
+ let location = token_range.start() + TextSize::try_from(i).unwrap();
  let range = TextRange::at(location, next_char.text_len() + TextSize::from(1));
  invalid_escape_sequence.push(Diagnostic::new(InvalidEscapeSequence(next_char), range));
  }
@@ -179,12 +168,16 @@ pub(crate) fn invalid_escape_sequence(
  )));
  }
  } else {
- let tok_start = if tok.is_f_string_middle() {
+ let tok_start = if token.is_f_string_middle() {
  // SAFETY: If this is a `FStringMiddle` token, then the indexer
  // must have the f-string range.
- indexer.f_string_range(tok_range.start()).unwrap().start()
+ indexer
+ .fstring_ranges()
+ .innermost(token_range.start())
+ .unwrap()
+ .start()
  } else {
- tok_range.start()
+ token_range.start()
  };
  // Turn into raw string.
  for diagnostic in &mut invalid_escape_sequence {

crates/ruff/src/rules/pycodestyle/snapshots/ruff__rules__pycodestyle__tests__W605_W605_2.py.snap

@@ -139,7 +139,7 @@ W605_2.py:44:11: W605 [*] Invalid escape sequence: `\{`
  44 |+value = rf'\{{1}}'
 45 45 | value = f'\{1}'
 46 46 | value = f'{1:\}'
-47 47 | 
+47 47 | value = f"{f"\{1}"}"
 
 W605_2.py:45:11: W605 [*] Invalid escape sequence: `\{`
  |
@@ -148,6 +148,7 @@ W605_2.py:45:11: W605 [*] Invalid escape sequence: `\{`
 45 | value = f'\{1}'
  | ^^ W605
 46 | value = f'{1:\}'
+47 | value = f"{f"\{1}"}"
  |
  = help: Add backslash to escape sequence
 
@@ -158,17 +159,17 @@ W605_2.py:45:11: W605 [*] Invalid escape sequence: `\{`
 45 |-value = f'\{1}'
  45 |+value = rf'\{1}'
 46 46 | value = f'{1:\}'
-47 47 | 
-48 48 | # Okay
+47 47 | value = f"{f"\{1}"}"
+48 48 | value = rf"{f"\{1}"}"
 
 W605_2.py:46:14: W605 [*] Invalid escape sequence: `\}`
  |
 44 | value = f'\{{1}}'
 45 | value = f'\{1}'
 46 | value = f'{1:\}'
  | ^^ W605
-47 | 
-48 | # Okay
+47 | value = f"{f"\{1}"}"
+48 | value = rf"{f"\{1}"}"
  |
  = help: Add backslash to escape sequence
 
@@ -178,8 +179,49 @@ W605_2.py:46:14: W605 [*] Invalid escape sequence: `\}`
 45 45 | value = f'\{1}'
 46 |-value = f'{1:\}'
  46 |+value = rf'{1:\}'
-47 47 | 
-48 48 | # Okay
-49 49 | value = rf'\{{1}}'
+47 47 | value = f"{f"\{1}"}"
+48 48 | value = rf"{f"\{1}"}"
+49 49 | 
+
+W605_2.py:47:14: W605 [*] Invalid escape sequence: `\{`
+ |
+45 | value = f'\{1}'
+46 | value = f'{1:\}'
+47 | value = f"{f"\{1}"}"
+ | ^^ W605
+48 | value = rf"{f"\{1}"}"
+ |
+ = help: Add backslash to escape sequence
+
+ℹ Fix
+44 44 | value = f'\{{1}}'
+45 45 | value = f'\{1}'
+46 46 | value = f'{1:\}'
+47 |-value = f"{f"\{1}"}"
+ 47 |+value = f"{rf"\{1}"}"
+48 48 | value = rf"{f"\{1}"}"
+49 49 | 
+50 50 | # Okay
+
+W605_2.py:48:15: W605 [*] Invalid escape sequence: `\{`
+ |
+46 | value = f'{1:\}'
+47 | value = f"{f"\{1}"}"
+48 | value = rf"{f"\{1}"}"
+ | ^^ W605
+49 | 
+50 | # Okay
+ |
+ = help: Add backslash to escape sequence
+
+ℹ Fix
+45 45 | value = f'\{1}'
+46 46 | value = f'{1:\}'
+47 47 | value = f"{f"\{1}"}"
+48 |-value = rf"{f"\{1}"}"
+ 48 |+value = rf"{rf"\{1}"}"
+49 49 | 
+50 50 | # Okay
+51 51 | value = rf'\{{1}}'