Use char-wise width instead of str-width (#12135)

## Summary

This PR updates various references in the linter to compute the
line-width for summing the width of each `char` in a `str` instead of
computing the width of the `str` itself.

Refer to #12133 for more details.

fixes: #12130 

## Test Plan

Add a file with null (`\0`) character which is zero-width. Run this test
case on `main` to make sure it panics and switch over to this branch to
make sure it doesn't panic now.

crates/ruff_linter/src/rules/isort/sorting.rs

@@ -3,7 +3,7 @@
 use std::{borrow::Cow, cmp::Ordering, cmp::Reverse};
 
 use natord;
-use unicode_width::UnicodeWidthStr;
+use unicode_width::UnicodeWidthChar;
 
 use ruff_python_stdlib::str;
 
@@ -106,7 +106,11 @@ impl<'a> ModuleKey<'a> {
 
         let maybe_length = (settings.length_sort
             || (settings.length_sort_straight && style == ImportStyle::Straight))
-            .then_some(name.map(str::width).unwrap_or_default() + level as usize);
+            .then_some(
+                name.map(|name| name.chars().map(|c| c.width().unwrap_or(0)).sum::<usize>())
+                    .unwrap_or_default()
+                    + level as usize,
+            );
 
         let distance = match level {
             0 => Distance::None,
@@ -157,7 +161,9 @@ impl<'a> MemberKey<'a> {
         let member_type = settings
             .order_by_type
             .then_some(member_type(name, settings));
-        let maybe_length = settings.length_sort.then_some(name.width());
+        let maybe_length = settings
+            .length_sort
+            .then(|| name.chars().map(|c| c.width().unwrap_or(0)).sum());
         let maybe_lowercase_name =
             (!settings.case_sensitive).then_some(NatOrdStr(maybe_lowercase(name)));
         let module_name = NatOrdStr::from(name);

crates/ruff_linter/src/rules/pycodestyle/mod.rs

@@ -34,6 +34,7 @@ mod tests {
     #[test_case(Rule::InvalidEscapeSequence, Path::new("W605_1.py"))]
     #[test_case(Rule::LineTooLong, Path::new("E501.py"))]
     #[test_case(Rule::LineTooLong, Path::new("E501_3.py"))]
+    #[test_case(Rule::LineTooLong, Path::new("E501_4.py"))]
     #[test_case(Rule::MixedSpacesAndTabs, Path::new("E101.py"))]
     #[test_case(Rule::ModuleImportNotAtTopOfFile, Path::new("E40.py"))]
     #[test_case(Rule::ModuleImportNotAtTopOfFile, Path::new("E402_0.py"))]

crates/ruff_linter/src/rules/pycodestyle/overlong.rs

@@ -1,7 +1,5 @@
 use std::ops::Deref;
 
-use unicode_width::UnicodeWidthStr;
-
 use ruff_python_trivia::{is_pragma_comment, CommentRanges};
 use ruff_source_file::Line;
 use ruff_text_size::{TextLen, TextRange};
@@ -61,7 +59,7 @@ impl Overlong {
         // begins before the limit.
         let last_chunk = chunks.last().unwrap_or(second_chunk);
         if last_chunk.contains("://") {
-            if width.get() - last_chunk.width() <= limit.value() as usize {
+            if width.get() - measure(last_chunk, tab_size).get() <= limit.value() as usize {
                 return None;
             }
         }