Use unicode-width to determine line-length instead of character count (#3714)

Cargo.lock

@@ -2033,6 +2033,7 @@ dependencies = [
  "textwrap",
  "thiserror",
  "toml",
+ "unicode-width",
 ]
 
 [[package]]

crates/ruff/Cargo.toml

@@ -58,6 +58,7 @@ rustpython-parser = { workspace = true }
 schemars = { workspace = true }
 semver = { version = "1.0.16" }
 serde = { workspace = true }
+serde_json = { workspace = true }
 shellexpand = { workspace = true }
 smallvec = { version = "1.10.0" }
 strum = { workspace = true }
@@ -65,7 +66,7 @@ strum_macros = { workspace = true }
 textwrap = { workspace = true }
 thiserror = { version = "1.0.38" }
 toml = { workspace = true }
-serde_json = { workspace = true }
+unicode-width = "0.1.10"
 
 [dev-dependencies]
 insta = { workspace = true, features = ["yaml", "redactions"] }

crates/ruff/src/checkers/physical_lines.rs

@@ -211,7 +211,7 @@ mod tests {
                 flags::Autofix::Enabled,
             )
         };
-        assert!(!check_with_max_line_length(6).is_empty());
-        assert!(check_with_max_line_length(7).is_empty());
+        assert_eq!(check_with_max_line_length(8), vec![]);
+        assert_eq!(check_with_max_line_length(8), vec![]);
     }
 }

crates/ruff/src/rules/flake8_simplify/rules/ast_if.rs

@@ -1,6 +1,7 @@
 use log::error;
 use rustc_hash::FxHashSet;
 use rustpython_parser::ast::{Cmpop, Constant, Expr, ExprContext, ExprKind, Stmt, StmtKind};
+use unicode_width::UnicodeWidthStr;
 
 use ruff_diagnostics::{AutofixKind, Diagnostic, Fix, Violation};
 use ruff_macros::{derive_message_formats, violation};
@@ -287,7 +288,7 @@ pub fn nested_if_statements(
                 if fix
                     .content
                     .universal_newlines()
-                    .all(|line| line.len() <= checker.settings.line_length)
+                    .all(|line| line.width() <= checker.settings.line_length)
                 {
                     diagnostic.amend(fix);
                 }
@@ -490,7 +491,7 @@ pub fn use_ternary_operator(checker: &mut Checker, stmt: &Stmt, parent: Option<&
     let contents = unparse_stmt(&ternary, checker.stylist);
 
     // Don't flag if the resulting expression would exceed the maximum line length.
-    if stmt.location.column() + contents.len() > checker.settings.line_length {
+    if stmt.location.column() + contents.width() > checker.settings.line_length {
         return;
     }
 
@@ -839,7 +840,7 @@ pub fn use_dict_get_with_default(
     );
 
     // Don't flag if the resulting expression would exceed the maximum line length.
-    if stmt.location.column() + contents.len() > checker.settings.line_length {
+    if stmt.location.column() + contents.width() > checker.settings.line_length {
         return;
     }
 

crates/ruff/src/rules/flake8_simplify/rules/ast_with.rs

@@ -1,5 +1,6 @@
 use log::error;
 use rustpython_parser::ast::{Located, Stmt, StmtKind, Withitem};
+use unicode_width::UnicodeWidthStr;
 
 use ruff_diagnostics::Diagnostic;
 use ruff_diagnostics::{AutofixKind, Violation};
@@ -117,7 +118,7 @@ pub fn multiple_with_statements(
                     if fix
                         .content
                         .universal_newlines()
-                        .all(|line| line.len() <= checker.settings.line_length)
+                        .all(|line| line.width() <= checker.settings.line_length)
                     {
                         diagnostic.amend(fix);
                     }

crates/ruff/src/rules/flake8_simplify/rules/reimplemented_builtin.rs

@@ -1,6 +1,7 @@
 use rustpython_parser::ast::{
     Cmpop, Comprehension, Constant, Expr, ExprContext, ExprKind, Location, Stmt, StmtKind, Unaryop,
 };
+use unicode_width::UnicodeWidthStr;
 
 use ruff_diagnostics::{AlwaysAutofixableViolation, Diagnostic, Fix};
 use ruff_macros::{derive_message_formats, violation};
@@ -211,7 +212,7 @@ pub fn convert_for_loop_to_any_all(checker: &mut Checker, stmt: &Stmt, sibling:
                 );
 
                 // Don't flag if the resulting expression would exceed the maximum line length.
-                if stmt.location.column() + contents.len() > checker.settings.line_length {
+                if stmt.location.column() + contents.width() > checker.settings.line_length {
                     return;
                 }
 
@@ -288,7 +289,7 @@ pub fn convert_for_loop_to_any_all(checker: &mut Checker, stmt: &Stmt, sibling:
                 );
 
                 // Don't flag if the resulting expression would exceed the maximum line length.
-                if stmt.location.column() + contents.len() > checker.settings.line_length {
+                if stmt.location.column() + contents.width() > checker.settings.line_length {
                     return;
                 }
 

crates/ruff/src/rules/isort/format.rs

@@ -1,4 +1,5 @@
 use ruff_python_ast::source_code::Stylist;
+use unicode_width::UnicodeWidthStr;
 
 use super::types::{AliasData, CommentSet, ImportFromData, Importable};
 
@@ -69,9 +70,9 @@ pub fn format_import_from(
             || aliases.len() == 1
             || aliases.iter().all(|(alias, _)| alias.asname.is_none()))
     {
-        let (single_line, import_length) =
+        let (single_line, import_width) =
             format_single_line(import_from, comments, aliases, is_first, stylist);
-        if import_length <= line_length || aliases.iter().any(|(alias, _)| alias.name == "*") {
+        if import_width <= line_length || aliases.iter().any(|(alias, _)| alias.name == "*") {
             return single_line;
         }
     }
@@ -90,7 +91,7 @@ fn format_single_line(
     stylist: &Stylist,
 ) -> (String, usize) {
     let mut output = String::with_capacity(CAPACITY);
-    let mut line_length = 0;
+    let mut line_width = 0;
 
     if !is_first && !comments.atop.is_empty() {
         output.push_str(stylist.line_ending());
@@ -104,28 +105,28 @@ fn format_single_line(
     output.push_str("from ");
     output.push_str(&module_name);
     output.push_str(" import ");
-    line_length += 5 + module_name.len() + 8;
+    line_width += 5 + module_name.width() + 8;
 
     for (index, (AliasData { name, asname }, comments)) in aliases.iter().enumerate() {
         if let Some(asname) = asname {
             output.push_str(name);
             output.push_str(" as ");
             output.push_str(asname);
-            line_length += name.len() + 4 + asname.len();
+            line_width += name.width() + 4 + asname.width();
         } else {
             output.push_str(name);
-            line_length += name.len();
+            line_width += name.width();
         }
         if index < aliases.len() - 1 {
             output.push_str(", ");
-            line_length += 2;
+            line_width += 2;
         }
 
         for comment in &comments.inline {
             output.push(' ');
             output.push(' ');
             output.push_str(comment);
-            line_length += 2 + comment.len();
+            line_width += 2 + comment.width();
         }
     }
 
@@ -133,12 +134,12 @@ fn format_single_line(
         output.push(' ');
         output.push(' ');
         output.push_str(comment);
-        line_length += 2 + comment.len();
+        line_width += 2 + comment.width();
     }
 
     output.push_str(stylist.line_ending());
 
-    (output, line_length)
+    (output, line_width)
 }
 
 /// Format an import-from statement in multi-line format.

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

@@ -25,12 +25,12 @@ static URL_REGEX: Lazy<Regex> = Lazy::new(|| Regex::new(r"^https?://\S+$").unwra
 
 pub fn is_overlong(
     line: &str,
-    line_length: usize,
+    line_width: usize,
     limit: usize,
     ignore_overlong_task_comments: bool,
     task_tags: &[String],
 ) -> bool {
-    if line_length <= limit {
+    if line_width <= limit {
         return false;
     }
 

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

@@ -2,6 +2,7 @@ use bitflags::bitflags;
 use rustpython_parser::ast::Location;
 use rustpython_parser::lexer::LexResult;
 use rustpython_parser::Tok;
+use unicode_width::UnicodeWidthStr;
 
 use ruff_python_ast::source_code::Locator;
 use ruff_python_ast::types::Range;
@@ -86,7 +87,7 @@ fn build_line<'a>(
         // TODO(charlie): "Mute" strings.
         let s;
         let text = if let Tok::String { value, .. } = tok {
-            s = format!("\"{}\"", "x".repeat(value.len()).clone());
+            s = format!("\"{}\"", "x".repeat(value.width()).clone());
             &s
         } else {
             locator.slice(Range {

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

@@ -1,4 +1,5 @@
 use rustpython_parser::ast::Location;
+use unicode_width::UnicodeWidthStr;
 
 use ruff_diagnostics::{Diagnostic, Violation};
 use ruff_macros::{derive_message_formats, violation};
@@ -34,8 +35,8 @@ pub struct DocLineTooLong(pub usize, pub usize);
 impl Violation for DocLineTooLong {
     #[derive_message_formats]
     fn message(&self) -> String {
-        let DocLineTooLong(length, limit) = self;
-        format!("Doc line too long ({length} > {limit} characters)")
+        let DocLineTooLong(width, limit) = self;
+        format!("Doc line too long ({width} > {limit} characters)")
     }
 }
 
@@ -45,19 +46,19 @@ pub fn doc_line_too_long(lineno: usize, line: &str, settings: &Settings) -> Opti
         return None;
     };
 
-    let line_length = line.chars().count();
+    let line_width = line.width();
     if is_overlong(
         line,
-        line_length,
+        line_width,
         limit,
         settings.pycodestyle.ignore_overlong_task_comments,
         &settings.task_tags,
     ) {
         Some(Diagnostic::new(
-            DocLineTooLong(line_length, limit),
+            DocLineTooLong(line_width, limit),
             Range::new(
                 Location::new(lineno + 1, limit),
-                Location::new(lineno + 1, line_length),
+                Location::new(lineno + 1, line.chars().count()),
             ),
         ))
     } else {

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

@@ -1,4 +1,5 @@
 use rustpython_parser::ast::Location;
+use unicode_width::UnicodeWidthStr;
 
 use ruff_diagnostics::{Diagnostic, Violation};
 use ruff_macros::{derive_message_formats, violation};
@@ -31,27 +32,27 @@ pub struct LineTooLong(pub usize, pub usize);
 impl Violation for LineTooLong {
     #[derive_message_formats]
     fn message(&self) -> String {
-        let LineTooLong(length, limit) = self;
-        format!("Line too long ({length} > {limit} characters)")
+        let LineTooLong(width, limit) = self;
+        format!("Line too long ({width} > {limit} characters)")
     }
 }
 
 /// E501
 pub fn line_too_long(lineno: usize, line: &str, settings: &Settings) -> Option<Diagnostic> {
-    let line_length = line.chars().count();
+    let line_width = line.width();
     let limit = settings.line_length;
     if is_overlong(
         line,
-        line_length,
+        line_width,
         limit,
         settings.pycodestyle.ignore_overlong_task_comments,
         &settings.task_tags,
     ) {
         Some(Diagnostic::new(
-            LineTooLong(line_length, limit),
+            LineTooLong(line_width, limit),
             Range::new(
                 Location::new(lineno + 1, limit),
-                Location::new(lineno + 1, line_length),
+                Location::new(lineno + 1, line.chars().count()),
             ),
         ))
     } else {

crates/ruff/src/rules/pycodestyle/snapshots/ruff__rules__pycodestyle__tests__E501_E501.py.snap

@@ -15,6 +15,19 @@ expression: diagnostics
     column: 123
   fix: ~
   parent: ~
+- kind:
+    name: LineTooLong
+    body: Line too long (95 > 88 characters)
+    suggestion: ~
+    fixable: false
+  location:
+    row: 16
+    column: 88
+  end_location:
+    row: 16
+    column: 88
+  fix: ~
+  parent: ~
 - kind:
     name: LineTooLong
     body: Line too long (127 > 88 characters)

crates/ruff_benchmark/Cargo.toml

@@ -32,3 +32,6 @@ mimalloc = "0.1.34"
 
 [target.'cfg(all(not(target_os = "windows"), not(target_os = "openbsd"), any(target_arch = "x86_64", target_arch = "aarch64", target_arch = "powerpc64")))'.dev-dependencies]
 tikv-jemallocator = "0.5.0"
+
+[features]
+logical_lines = [ "ruff/logical_lines" ]