From 3f5a91cecfd113d9e4a8f40f960293457adc8db0 Mon Sep 17 00:00:00 2001
From: Brent Westbrook <36778786+ntBre@users.noreply.github.com>
Date: Wed, 23 Sep 2026 13:25:37 -0400
Subject: [PATCH] Stabilize pragma comment width handling (#28795)

Summary
--

I wasn't really planning to do a full stabilization pass, but I quickly skimmed through `preview.rs`
and remembered that the isort pragma change was kind a bug fix but technically breaking and thought
we might want to stabilize it.

This PR stabilizes the isort pragma comment width handling introduced in #27313, along with the
related pragma handling for `E501` and `W505` from #24071. There was a comment about also
stabilizing the related formatter preview feature on the function from #24071, so that is stabilized
here too.

I'm fine holding off on this, especially if the formatter change is a better fit for the 2027 style
guide. Like I said above, I mostly wanted to stabilize the isort change, but that snowballed a bit
since the helpers were shared.

Test Plan
--

Updated existing snapshots
---
 .../isort/fit_line_length_merged_pragma.py    |  2 +-
 .../isort/fit_line_length_mixed_pragma.py     |  2 +-
 .../fixtures/isort/fit_line_length_pragma.py  |  4 +-
 crates/ruff_linter/src/line_width.rs          | 45 ++---------------
 crates/ruff_linter/src/preview.rs             | 11 ----
 crates/ruff_linter/src/rules/isort/format.rs  | 15 ++----
 crates/ruff_linter/src/rules/isort/mod.rs     | 34 ++-----------
 .../src/rules/isort/rules/organize_imports.rs |  1 -
 ..._fit_line_length_merged_pragma_fixed.snap} |  2 +-
 ...ine_length_merged_pragma_fixed_stable.snap | 23 ---------
 ...ests__fit_line_length_mixed_pragma.py.snap | 26 ++++------
 ...ort__tests__fit_line_length_pragma.py.snap | 41 ++++-----------
 ...les__isort__tests__inline_comments.py.snap | 30 +++++------
 ...view__fit_line_length_mixed_pragma.py.snap | 24 ---------
 ...s__preview__fit_line_length_pragma.py.snap | 25 ----------
 .../ruff_linter/src/rules/pycodestyle/mod.rs  |  2 +-
 .../src/rules/pycodestyle/overlong.rs         | 19 +++----
 .../pycodestyle/rules/doc_line_too_long.rs    |  1 -
 .../rules/pycodestyle/rules/line_too_long.rs  |  1 -
 ...tyle__tests__line-too-long_E501_5.py.snap} |  0
 .../fixtures/ruff/trailing_pragma_nested.py   |  6 +--
 .../src/comments/format.rs                    | 22 +++-----
 crates/ruff_python_formatter/src/preview.rs   | 10 ----
 .../format@trailing_pragma_nested.py.snap     | 50 ++++---------------
 docs/formatter/black.md                       |  2 +
 25 files changed, 80 insertions(+), 318 deletions(-)
 rename crates/ruff_linter/src/rules/isort/snapshots/{ruff_linter__rules__isort__tests__fit_line_length_merged_pragma_fixed_preview.snap => ruff_linter__rules__isort__tests__fit_line_length_merged_pragma_fixed.snap} (97%)
 delete mode 100644 crates/ruff_linter/src/rules/isort/snapshots/ruff_linter__rules__isort__tests__fit_line_length_merged_pragma_fixed_stable.snap
 delete mode 100644 crates/ruff_linter/src/rules/isort/snapshots/ruff_linter__rules__isort__tests__preview__fit_line_length_mixed_pragma.py.snap
 delete mode 100644 crates/ruff_linter/src/rules/isort/snapshots/ruff_linter__rules__isort__tests__preview__fit_line_length_pragma.py.snap
 rename crates/ruff_linter/src/rules/pycodestyle/snapshots/{ruff_linter__rules__pycodestyle__tests__preview__line-too-long_E501_5.py.snap => ruff_linter__rules__pycodestyle__tests__line-too-long_E501_5.py.snap} (100%)

diff --git a/crates/ruff_linter/resources/test/fixtures/isort/fit_line_length_merged_pragma.py b/crates/ruff_linter/resources/test/fixtures/isort/fit_line_length_merged_pragma.py
index 769e7cc701..0badd6de62 100644
--- a/crates/ruff_linter/resources/test/fixtures/isort/fit_line_length_merged_pragma.py
+++ b/crates/ruff_linter/resources/test/fixtures/isort/fit_line_length_merged_pragma.py
@@ -9,7 +9,7 @@ from aaaaaaaaaaaaaaaaaaaaaaaa.aaaaaaaaaaaaaaaaaaaaaaa import (  # explain
 # non-pragma prefix is 86 columns.
 from bbbbbbbbbbbbbbbbbbbbbbbbbbbbbb.bbbbbbbbbbbbbbbbbbbbbbbbbbbbbb import x  # explain  # noqa: TID251
 
-# Separate comments with the pragma first: when isort collapses this import in preview,
+# Separate comments with the pragma first: when isort collapses this import,
 # the merged comment token is pragma-prefixed, so E501 strips it entirely and the
 # collapsed 104-column line is fine.
 from ccccccccccccccccccccccccccccccc.ccccccccccccccccccccccccccccccc import (  # noqa: TID251
diff --git a/crates/ruff_linter/resources/test/fixtures/isort/fit_line_length_mixed_pragma.py b/crates/ruff_linter/resources/test/fixtures/isort/fit_line_length_mixed_pragma.py
index d2b0744707..342c34f104 100644
--- a/crates/ruff_linter/resources/test/fixtures/isort/fit_line_length_mixed_pragma.py
+++ b/crates/ruff_linter/resources/test/fixtures/isort/fit_line_length_mixed_pragma.py
@@ -1,5 +1,5 @@
 # The next import fits on one line once the trailing pragma is excluded from the width
-# (the `# keep this` prefix still counts); in preview it should not be wrapped.
+# (the `# keep this` prefix still counts); it should not be wrapped.
 from aaaaaaaaaaaaaaaaaaaaaaaaaaaaaa.aaaaaaaaaaaaaaaaaaaaaaaaaaaaaa import x  # keep this  # noqa: TID251
 # The next import exceeds the line length even without the trailing pragma
 # (code plus the `# keep this` prefix is 89 columns); it must always be wrapped.
diff --git a/crates/ruff_linter/resources/test/fixtures/isort/fit_line_length_pragma.py b/crates/ruff_linter/resources/test/fixtures/isort/fit_line_length_pragma.py
index 341bad469d..b041fdaf68 100644
--- a/crates/ruff_linter/resources/test/fixtures/isort/fit_line_length_pragma.py
+++ b/crates/ruff_linter/resources/test/fixtures/isort/fit_line_length_pragma.py
@@ -1,5 +1,5 @@
 # The next import fits on one line once the pragma comment is excluded from the width;
-# in preview it should not be wrapped (the `# noqa` must stay effective).
+# it should not be wrapped (the `# noqa` must stay effective).
 from aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa.aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa import x  # noqa: TID251
 # The next import exceeds the line length even without the pragma comment;
 # it must still be wrapped.
@@ -8,6 +8,6 @@ from bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb.bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb
 
 def f():
     # The next import fits on one line once the pragma comment is excluded from the
-    # width, so in preview it should not be wrapped.
+    # width, so it should not be wrapped.
     from cccccccccccccccccccccccccccccc.ccccccccccccccccccccccccccccccccccccc import bar  # noqa: PLC0415
     bar()
diff --git a/crates/ruff_linter/src/line_width.rs b/crates/ruff_linter/src/line_width.rs
index a04360ef9d..ad159c12f5 100644
--- a/crates/ruff_linter/src/line_width.rs
+++ b/crates/ruff_linter/src/line_width.rs
@@ -9,35 +9,7 @@ use unicode_width::UnicodeWidthChar;
 
 use ruff_cache::{CacheKey, CacheKeyHasher};
 use ruff_macros::CacheKey;
-use ruff_python_trivia::{find_trailing_pragma_offset, is_pragma_comment, tab_offset};
-
-use crate::preview::{
-    is_pragma_excluded_from_import_width_enabled, is_trailing_pragma_in_line_length_enabled,
-};
-use crate::settings::types::PreviewMode;
-
-/// Returns the offset within `comment` at which the pragma comment excluded from line-length
-/// measurement begins, or `None` if the comment contains no such pragma.
-///
-/// This is the shared policy for how pragma comments (e.g., `# noqa: F401` or `# type: ignore`)
-/// are excluded when measuring line width, used by `line-too-long` (E501) and
-/// `doc-line-too-long` (W505), and, in preview mode, by isort's (I001) decision of whether an
-/// import fits on one line (see [`LineWidthBuilder::add_comment`]). The formatter applies the
-/// equivalent policy when measuring comment widths.
-///
-/// In stable mode, only comments that are pragmas in their entirety are excluded (the returned
-/// offset is `0`). In preview mode, a trailing pragma within a mixed comment (e.g.,
-/// `# explanation  # noqa: F401`) is also excluded, in which case the offset points at the `#`
-/// that begins the pragma.
-pub(crate) fn pragma_offset_for_line_length(comment: &str, preview: PreviewMode) -> Option<usize> {
-    if is_trailing_pragma_in_line_length_enabled(preview) {
-        find_trailing_pragma_offset(comment)
-    } else if is_pragma_comment(comment) {
-        Some(0)
-    } else {
-        None
-    }
-}
+use ruff_python_trivia::{find_trailing_pragma_offset, tab_offset};
 
 /// The length of a line of text that is considered too long.
 ///
@@ -267,8 +239,8 @@ impl LineWidthBuilder {
     }
 
     /// Adds the width of a trailing comment, including the standard two-space separator that
-    /// precedes it. In preview mode, any pragma comment is excluded per
-    /// [`pragma_offset_for_line_length`].
+    /// precedes it. Pragma suffixes are excluded per [`find_trailing_pragma_offset`], while
+    /// any preceding non-pragma comment text still contributes to the width.
     ///
     /// Pragma comments are excluded so that adding one to a line never affects whether the line
     /// is considered to fit, consistent with how `line-too-long` (E501) measures lines. For
@@ -281,16 +253,9 @@ impl LineWidthBuilder {
     ///     member,  # noqa: PLC0415
     /// )
     /// ```
-    ///
-    /// Unlike E501, which has always stripped whole-pragma comments on stable, the exclusion
-    /// changes how imports are formatted, so it is preview-gated in its entirety: on stable, the
-    /// full comment width is counted.
     #[must_use]
-    pub(crate) fn add_comment(self, comment: &str, preview: PreviewMode) -> Self {
-        if !is_pragma_excluded_from_import_width_enabled(preview) {
-            return self.add_width(2).add_str(comment);
-        }
-        let counted = match pragma_offset_for_line_length(comment, preview) {
+    pub(crate) fn add_comment(self, comment: &str) -> Self {
+        let counted = match find_trailing_pragma_offset(comment) {
             Some(offset) => comment[..offset].trim_end(),
             None => comment,
         };
diff --git a/crates/ruff_linter/src/preview.rs b/crates/ruff_linter/src/preview.rs
index ca7c51d450..bef07a1564 100644
--- a/crates/ruff_linter/src/preview.rs
+++ b/crates/ruff_linter/src/preview.rs
@@ -329,12 +329,6 @@ pub(crate) const fn is_up006_future_annotations_fix_enabled(settings: &LinterSet
     settings.preview.is_enabled()
 }
 
-// https://github.com/astral-sh/ruff/pull/24071
-// Make sure to stabilize the corresponding formatter preview behavior when stabilizing this preview style.
-pub(crate) const fn is_trailing_pragma_in_line_length_enabled(preview: PreviewMode) -> bool {
-    preview.is_enabled()
-}
-
 // https://github.com/astral-sh/ruff/pull/24371
 pub(crate) const fn is_collapsible_if_fix_safe_enabled(settings: &LinterSettings) -> bool {
     settings.preview.is_enabled()
@@ -362,11 +356,6 @@ pub(crate) const fn is_b005_precise_diagnostic_enabled(settings: &LinterSettings
     settings.preview.is_enabled()
 }
 
-// https://github.com/astral-sh/ruff/pull/27313
-pub(crate) const fn is_pragma_excluded_from_import_width_enabled(preview: PreviewMode) -> bool {
-    preview.is_enabled()
-}
-
 // https://github.com/astral-sh/ruff/pull/27666
 pub(crate) const fn is_rule_categories_enabled(preview: PreviewMode) -> bool {
     preview.is_enabled()
diff --git a/crates/ruff_linter/src/rules/isort/format.rs b/crates/ruff_linter/src/rules/isort/format.rs
index 90cdc57238..959c87a2dc 100644
--- a/crates/ruff_linter/src/rules/isort/format.rs
+++ b/crates/ruff_linter/src/rules/isort/format.rs
@@ -1,7 +1,6 @@
 use ruff_python_codegen::Stylist;
 
 use crate::line_width::{LineLength, LineWidthBuilder};
-use crate::settings::types::PreviewMode;
 
 use super::types::{AliasData, ImportCommentSet, ImportFromCommentSet, ImportFromData, Importable};
 
@@ -55,7 +54,6 @@ pub(crate) fn format_import_from(
     force_wrap_aliases: bool,
     is_first: bool,
     trailing_comma: bool,
-    preview: PreviewMode,
 ) -> String {
     if aliases.len() == 1
         && aliases
@@ -69,7 +67,6 @@ pub(crate) fn format_import_from(
             is_first,
             stylist,
             indentation_width,
-            preview,
         );
         return single_line;
     }
@@ -98,7 +95,6 @@ pub(crate) fn format_import_from(
             is_first,
             stylist,
             indentation_width,
-            preview,
         );
         if import_width <= line_length || aliases.iter().any(|(alias, _)| alias.name == "*") {
             return single_line;
@@ -118,7 +114,6 @@ fn format_single_line(
     is_first: bool,
     stylist: &Stylist,
     indentation_width: LineWidthBuilder,
-    preview: PreviewMode,
 ) -> (String, LineWidthBuilder) {
     let mut output = String::with_capacity(CAPACITY);
     let mut line_width = indentation_width;
@@ -161,7 +156,7 @@ fn format_single_line(
         output.push(' ');
         output.push(' ');
         output.push_str(comment);
-        line_width = line_width.add_comment(comment, preview);
+        line_width = line_width.add_comment(comment);
     }
 
     for (_, comments) in aliases {
@@ -169,21 +164,21 @@ fn format_single_line(
             output.push(' ');
             output.push(' ');
             output.push_str(comment);
-            line_width = line_width.add_comment(comment, preview);
+            line_width = line_width.add_comment(comment);
         }
 
         for comment in &comments.inline {
             output.push(' ');
             output.push(' ');
             output.push_str(comment);
-            line_width = line_width.add_comment(comment, preview);
+            line_width = line_width.add_comment(comment);
         }
 
         for comment in &comments.trailing {
             output.push(' ');
             output.push(' ');
             output.push_str(comment);
-            line_width = line_width.add_comment(comment, preview);
+            line_width = line_width.add_comment(comment);
         }
     }
 
@@ -191,7 +186,7 @@ fn format_single_line(
         output.push(' ');
         output.push(' ');
         output.push_str(comment);
-        line_width = line_width.add_comment(comment, preview);
+        line_width = line_width.add_comment(comment);
     }
 
     output.push_str(&stylist.line_ending());
diff --git a/crates/ruff_linter/src/rules/isort/mod.rs b/crates/ruff_linter/src/rules/isort/mod.rs
index 062cfe94e5..78f94d4405 100644
--- a/crates/ruff_linter/src/rules/isort/mod.rs
+++ b/crates/ruff_linter/src/rules/isort/mod.rs
@@ -20,7 +20,6 @@ use types::{AliasData, ImportBlock, TrailingComma};
 use crate::Locator;
 use crate::line_width::{LineLength, LineWidthBuilder};
 use crate::package::PackageRoot;
-use crate::settings::types::PreviewMode;
 use ruff_python_ast::PythonVersion;
 
 mod annotate;
@@ -78,7 +77,6 @@ pub(crate) fn format_imports(
     source_type: PySourceType,
     target_version: PythonVersion,
     settings: &Settings,
-    preview: PreviewMode,
     tokens: &Tokens,
 ) -> String {
     let trailer = &block.trailer;
@@ -106,7 +104,6 @@ pub(crate) fn format_imports(
             package,
             target_version,
             settings,
-            preview,
         );
 
         if !block_output.is_empty() && !output.is_empty() {
@@ -163,7 +160,6 @@ fn format_import_block(
     package: Option<PackageRoot<'_>>,
     target_version: PythonVersion,
     settings: &Settings,
-    preview: PreviewMode,
 ) -> String {
     #[derive(Debug, Copy, Clone, PartialEq, Eq)]
     enum LineInsertion {
@@ -293,7 +289,6 @@ fn format_import_block(
                         is_first_statement,
                         settings.split_on_trailing_comma
                             && matches!(trailing_comma, TrailingComma::Present),
-                        preview,
                     ));
 
                     if settings.from_first {
@@ -323,7 +318,7 @@ mod tests {
     use crate::registry::Rule;
     use crate::rules::isort::categorize::{ImportSection, KnownModules};
     use crate::settings::LinterSettings;
-    use crate::settings::types::{IdentifierPattern, PreviewMode};
+    use crate::settings::types::IdentifierPattern;
     use crate::source_kind::SourceKind;
     use crate::test::{test_contents, test_path, test_resource_path};
 
@@ -399,38 +394,19 @@ mod tests {
         Ok(())
     }
 
-    #[test_case(Path::new("fit_line_length_mixed_pragma.py"))]
-    #[test_case(Path::new("fit_line_length_pragma.py"))]
-    fn preview(path: &Path) -> Result<()> {
-        let snapshot = format!("preview__{}", path.to_string_lossy());
-        let diagnostics = test_path(
-            Path::new("isort").join(path).as_path(),
-            &LinterSettings {
-                preview: PreviewMode::Enabled,
-                src: vec![test_resource_path("fixtures/isort")],
-                ..LinterSettings::for_rule(Rule::UnsortedImports)
-            },
-        )?;
-        assert_diagnostics!(snapshot, diagnostics);
-        Ok(())
-    }
-
     /// Fixing I001 must never leave behind a line that E501 then flags.
     ///
     /// isort excludes pragma comments (e.g., `# noqa: TID251`) from its width computation
     /// per comment, while E501 measures the emitted line's single comment token as a whole.
     /// When isort merges separate comments onto one line (e.g., a statement-level `# explain`
     /// and an alias-level `# noqa`), the two computations could disagree; this test verifies
-    /// that the fix nonetheless converges to output that E501 accepts, in both stable and
-    /// preview modes.
-    #[test_case(PreviewMode::Disabled, "stable")]
-    #[test_case(PreviewMode::Enabled, "preview")]
-    fn no_line_too_long_after_fix(preview: PreviewMode, label: &str) -> Result<()> {
+    /// that the fix nonetheless converges to output that E501 accepts.
+    #[test]
+    fn no_line_too_long_after_fix() -> Result<()> {
         let path = test_resource_path("fixtures").join("isort/fit_line_length_merged_pragma.py");
         let source_type = SourceType::Python(PySourceType::from(&path));
         let source_kind = SourceKind::from_path(&path, source_type)?.expect("valid source");
         let settings = LinterSettings {
-            preview,
             src: vec![test_resource_path("fixtures/isort")],
             ..LinterSettings::for_rules([Rule::UnsortedImports, Rule::LineTooLong])
         };
@@ -438,7 +414,7 @@ mod tests {
         // `test_contents` applies fixes to convergence (and panics if they fail to converge).
         let (_, transformed) = test_contents(&source_kind, &path, &settings);
         insta::assert_snapshot!(
-            format!("fit_line_length_merged_pragma_fixed_{label}"),
+            "fit_line_length_merged_pragma_fixed",
             transformed.source_code()
         );
 
diff --git a/crates/ruff_linter/src/rules/isort/rules/organize_imports.rs b/crates/ruff_linter/src/rules/isort/rules/organize_imports.rs
index e0aa2f553e..8215f8d5a3 100644
--- a/crates/ruff_linter/src/rules/isort/rules/organize_imports.rs
+++ b/crates/ruff_linter/src/rules/isort/rules/organize_imports.rs
@@ -170,7 +170,6 @@ pub(crate) fn organize_imports(
         source_type,
         target_version,
         &settings.isort,
-        settings.preview,
         tokens,
     );
 
diff --git a/crates/ruff_linter/src/rules/isort/snapshots/ruff_linter__rules__isort__tests__fit_line_length_merged_pragma_fixed_preview.snap b/crates/ruff_linter/src/rules/isort/snapshots/ruff_linter__rules__isort__tests__fit_line_length_merged_pragma_fixed.snap
similarity index 97%
rename from crates/ruff_linter/src/rules/isort/snapshots/ruff_linter__rules__isort__tests__fit_line_length_merged_pragma_fixed_preview.snap
rename to crates/ruff_linter/src/rules/isort/snapshots/ruff_linter__rules__isort__tests__fit_line_length_merged_pragma_fixed.snap
index 38ba563037..d78f1e1f44 100644
--- a/crates/ruff_linter/src/rules/isort/snapshots/ruff_linter__rules__isort__tests__fit_line_length_merged_pragma_fixed_preview.snap
+++ b/crates/ruff_linter/src/rules/isort/snapshots/ruff_linter__rules__isort__tests__fit_line_length_merged_pragma_fixed.snap
@@ -11,7 +11,7 @@ from aaaaaaaaaaaaaaaaaaaaaaaa.aaaaaaaaaaaaaaaaaaaaaaa import x  # explain  # noq
 # non-pragma prefix is 86 columns.
 from bbbbbbbbbbbbbbbbbbbbbbbbbbbbbb.bbbbbbbbbbbbbbbbbbbbbbbbbbbbbb import x  # explain  # noqa: TID251
 
-# Separate comments with the pragma first: when isort collapses this import in preview,
+# Separate comments with the pragma first: when isort collapses this import,
 # the merged comment token is pragma-prefixed, so E501 strips it entirely and the
 # collapsed 104-column line is fine.
 from ccccccccccccccccccccccccccccccc.ccccccccccccccccccccccccccccccc import x  # noqa: TID251  # explain
diff --git a/crates/ruff_linter/src/rules/isort/snapshots/ruff_linter__rules__isort__tests__fit_line_length_merged_pragma_fixed_stable.snap b/crates/ruff_linter/src/rules/isort/snapshots/ruff_linter__rules__isort__tests__fit_line_length_merged_pragma_fixed_stable.snap
deleted file mode 100644
index aeff3e15ca..0000000000
--- a/crates/ruff_linter/src/rules/isort/snapshots/ruff_linter__rules__isort__tests__fit_line_length_merged_pragma_fixed_stable.snap
+++ /dev/null
@@ -1,23 +0,0 @@
----
-source: crates/ruff_linter/src/rules/isort/mod.rs
-expression: transformed.source_code()
----
-# Separate statement-level and alias-level comments that isort merges onto one line
-# when collapsing. The merged comment token is 89 columns with the `# explain` prefix
-# counted, so the import must not end up on an overlong single line.
-from aaaaaaaaaaaaaaaaaaaaaaaa.aaaaaaaaaaaaaaaaaaaaaaa import (  # explain
-    x,  # noqa: TID251
-)
-
-# A single mixed comment on an already-collapsed 102-column line. The code plus the
-# non-pragma prefix is 86 columns.
-from bbbbbbbbbbbbbbbbbbbbbbbbbbbbbb.bbbbbbbbbbbbbbbbbbbbbbbbbbbbbb import (
-    x,  # explain  # noqa: TID251
-)
-
-# Separate comments with the pragma first: when isort collapses this import in preview,
-# the merged comment token is pragma-prefixed, so E501 strips it entirely and the
-# collapsed 104-column line is fine.
-from ccccccccccccccccccccccccccccccc.ccccccccccccccccccccccccccccccc import (  # noqa: TID251
-    x,  # explain
-)
diff --git a/crates/ruff_linter/src/rules/isort/snapshots/ruff_linter__rules__isort__tests__fit_line_length_mixed_pragma.py.snap b/crates/ruff_linter/src/rules/isort/snapshots/ruff_linter__rules__isort__tests__fit_line_length_mixed_pragma.py.snap
index a1a4fd29d0..6b7e431775 100644
--- a/crates/ruff_linter/src/rules/isort/snapshots/ruff_linter__rules__isort__tests__fit_line_length_mixed_pragma.py.snap
+++ b/crates/ruff_linter/src/rules/isort/snapshots/ruff_linter__rules__isort__tests__fit_line_length_mixed_pragma.py.snap
@@ -5,24 +5,20 @@ I001 [*] Import block is un-sorted or un-formatted
  --> fit_line_length_mixed_pragma.py:3:1
   |
 1 |   # The next import fits on one line once the trailing pragma is excluded from the width
-2 |   # (the `# keep this` prefix still counts); in preview it should not be wrapped.
+2 |   # (the `# keep this` prefix still counts); it should not be wrapped.
 3 | / from aaaaaaaaaaaaaaaaaaaaaaaaaaaaaa.aaaaaaaaaaaaaaaaaaaaaaaaaaaaaa import x  # keep this  # noqa: TID251
 4 | | # The next import exceeds the line length even without the trailing pragma
 5 | | # (code plus the `# keep this` prefix is 89 columns); it must always be wrapped.
 6 | | from bbbbbbbbbbbbbbbbbbbbbbbbbbbbbb.bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb import x  # keep this  # noqa: TID251
   | |____________________________________________________________________________^
 help: Organize imports
-   |
-2  | # (the `# keep this` prefix still counts); in preview it should not be wrapped.
-   - from aaaaaaaaaaaaaaaaaaaaaaaaaaaaaa.aaaaaaaaaaaaaaaaaaaaaaaaaaaaaa import x  # keep this  # noqa: TID251
-3  + from aaaaaaaaaaaaaaaaaaaaaaaaaaaaaa.aaaaaaaaaaaaaaaaaaaaaaaaaaaaaa import (
-4  +     x,  # keep this  # noqa: TID251
-5  + )
-6  +
-7  | # The next import exceeds the line length even without the trailing pragma
-8  | # (code plus the `# keep this` prefix is 89 columns); it must always be wrapped.
-   - from bbbbbbbbbbbbbbbbbbbbbbbbbbbbbb.bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb import x  # keep this  # noqa: TID251
-9  + from bbbbbbbbbbbbbbbbbbbbbbbbbbbbbb.bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb import (
-10 +     x,  # keep this  # noqa: TID251
-11 + )
-   |
+  |
+3 | from aaaaaaaaaaaaaaaaaaaaaaaaaaaaaa.aaaaaaaaaaaaaaaaaaaaaaaaaaaaaa import x  # keep this  # noqa: TID251
+4 +
+5 | # The next import exceeds the line length even without the trailing pragma
+6 | # (code plus the `# keep this` prefix is 89 columns); it must always be wrapped.
+  - from bbbbbbbbbbbbbbbbbbbbbbbbbbbbbb.bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb import x  # keep this  # noqa: TID251
+7 + from bbbbbbbbbbbbbbbbbbbbbbbbbbbbbb.bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb import (
+8 +     x,  # keep this  # noqa: TID251
+9 + )
+  |
diff --git a/crates/ruff_linter/src/rules/isort/snapshots/ruff_linter__rules__isort__tests__fit_line_length_pragma.py.snap b/crates/ruff_linter/src/rules/isort/snapshots/ruff_linter__rules__isort__tests__fit_line_length_pragma.py.snap
index 258b51f527..90508084eb 100644
--- a/crates/ruff_linter/src/rules/isort/snapshots/ruff_linter__rules__isort__tests__fit_line_length_pragma.py.snap
+++ b/crates/ruff_linter/src/rules/isort/snapshots/ruff_linter__rules__isort__tests__fit_line_length_pragma.py.snap
@@ -5,7 +5,7 @@ I001 [*] Import block is un-sorted or un-formatted
  --> fit_line_length_pragma.py:3:1
   |
 1 |   # The next import fits on one line once the pragma comment is excluded from the width;
-2 |   # in preview it should not be wrapped (the `# noqa` must stay effective).
+2 |   # it should not be wrapped (the `# noqa` must stay effective).
 3 | / from aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa.aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa import x  # noqa: TID251
 4 | | # The next import exceeds the line length even without the pragma comment;
 5 | | # it must still be wrapped.
@@ -13,36 +13,13 @@ I001 [*] Import block is un-sorted or un-formatted
   | |_________________________________________________________________________________________^
 help: Organize imports
    |
-2  | # in preview it should not be wrapped (the `# noqa` must stay effective).
-   - from aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa.aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa import x  # noqa: TID251
-3  + from aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa.aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa import (
-4  +     x,  # noqa: TID251
-5  + )
-6  +
-7  | # The next import exceeds the line length even without the pragma comment;
-8  | # it must still be wrapped.
+3  | from aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa.aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa import x  # noqa: TID251
+4  +
+5  | # The next import exceeds the line length even without the pragma comment;
+6  | # it must still be wrapped.
    - from bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb.bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb import x  # noqa: TID251
-9  + from bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb.bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb import (
-10 +     x,  # noqa: TID251
-11 + )
-12 |
-   |
-
-I001 [*] Import block is un-sorted or un-formatted
-  --> fit_line_length_pragma.py:12:5
-   |
-10 |     # The next import fits on one line once the pragma comment is excluded from the
-11 |     # width, so in preview it should not be wrapped.
-12 |     from cccccccccccccccccccccccccccccc.ccccccccccccccccccccccccccccccccccccc import bar  # noqa: PLC0415
-   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
-13 |     bar()
-   |
-help: Organize imports
-   |
-11 |     # width, so in preview it should not be wrapped.
-   -     from cccccccccccccccccccccccccccccc.ccccccccccccccccccccccccccccccccccccc import bar  # noqa: PLC0415
-12 +     from cccccccccccccccccccccccccccccc.ccccccccccccccccccccccccccccccccccccc import (
-13 +         bar,  # noqa: PLC0415
-14 +     )
-15 |     bar()
+7  + from bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb.bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb import (
+8  +     x,  # noqa: TID251
+9  + )
+10 |
    |
diff --git a/crates/ruff_linter/src/rules/isort/snapshots/ruff_linter__rules__isort__tests__inline_comments.py.snap b/crates/ruff_linter/src/rules/isort/snapshots/ruff_linter__rules__isort__tests__inline_comments.py.snap
index 1e561c6670..1af553f935 100644
--- a/crates/ruff_linter/src/rules/isort/snapshots/ruff_linter__rules__isort__tests__inline_comments.py.snap
+++ b/crates/ruff_linter/src/rules/isort/snapshots/ruff_linter__rules__isort__tests__inline_comments.py.snap
@@ -17,21 +17,15 @@ I001 [*] Import block is un-sorted or un-formatted
 11 | | from d.prometheus.metrics import TERMINAL_CURRENTLY_RUNNING_TOTAL, OTHER_RUNNING_TOTAL  # type:ignore[attr-defined]
    | |______________________________________________________________________________________^
 help: Organize imports
-   |
-3  | )
-   -
-4  | from b.prometheus.metrics import (
-5  |     TERMINAL_CURRENTLY_RUNNING_TOTAL,  # type:ignore[attr-defined]
-6  | )
-   -
-   - from c.prometheus.metrics import TERMINAL_CURRENTLY_RUNNING_TOTAL  # type:ignore[attr-defined]
-   -
-   - from d.prometheus.metrics import TERMINAL_CURRENTLY_RUNNING_TOTAL, OTHER_RUNNING_TOTAL  # type:ignore[attr-defined]
-7  + from c.prometheus.metrics import (
-8  +     TERMINAL_CURRENTLY_RUNNING_TOTAL,  # type:ignore[attr-defined]
-9  + )
-10 + from d.prometheus.metrics import (  # type:ignore[attr-defined]
-11 +     OTHER_RUNNING_TOTAL,
-12 +     TERMINAL_CURRENTLY_RUNNING_TOTAL,
-13 + )
-   |
+  |
+3 | )
+  -
+4 | from b.prometheus.metrics import (
+5 |     TERMINAL_CURRENTLY_RUNNING_TOTAL,  # type:ignore[attr-defined]
+6 | )
+  -
+7 | from c.prometheus.metrics import TERMINAL_CURRENTLY_RUNNING_TOTAL  # type:ignore[attr-defined]
+  -
+  - from d.prometheus.metrics import TERMINAL_CURRENTLY_RUNNING_TOTAL, OTHER_RUNNING_TOTAL  # type:ignore[attr-defined]
+8 + from d.prometheus.metrics import OTHER_RUNNING_TOTAL, TERMINAL_CURRENTLY_RUNNING_TOTAL  # type:ignore[attr-defined]
+  |
diff --git a/crates/ruff_linter/src/rules/isort/snapshots/ruff_linter__rules__isort__tests__preview__fit_line_length_mixed_pragma.py.snap b/crates/ruff_linter/src/rules/isort/snapshots/ruff_linter__rules__isort__tests__preview__fit_line_length_mixed_pragma.py.snap
deleted file mode 100644
index 19e870e003..0000000000
--- a/crates/ruff_linter/src/rules/isort/snapshots/ruff_linter__rules__isort__tests__preview__fit_line_length_mixed_pragma.py.snap
+++ /dev/null
@@ -1,24 +0,0 @@
----
-source: crates/ruff_linter/src/rules/isort/mod.rs
----
-I001 [*] Import block is un-sorted or un-formatted
- --> fit_line_length_mixed_pragma.py:3:1
-  |
-1 |   # The next import fits on one line once the trailing pragma is excluded from the width
-2 |   # (the `# keep this` prefix still counts); in preview it should not be wrapped.
-3 | / from aaaaaaaaaaaaaaaaaaaaaaaaaaaaaa.aaaaaaaaaaaaaaaaaaaaaaaaaaaaaa import x  # keep this  # noqa: TID251
-4 | | # The next import exceeds the line length even without the trailing pragma
-5 | | # (code plus the `# keep this` prefix is 89 columns); it must always be wrapped.
-6 | | from bbbbbbbbbbbbbbbbbbbbbbbbbbbbbb.bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb import x  # keep this  # noqa: TID251
-  | |____________________________________________________________________________^
-help: Organize imports
-  |
-3 | from aaaaaaaaaaaaaaaaaaaaaaaaaaaaaa.aaaaaaaaaaaaaaaaaaaaaaaaaaaaaa import x  # keep this  # noqa: TID251
-4 +
-5 | # The next import exceeds the line length even without the trailing pragma
-6 | # (code plus the `# keep this` prefix is 89 columns); it must always be wrapped.
-  - from bbbbbbbbbbbbbbbbbbbbbbbbbbbbbb.bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb import x  # keep this  # noqa: TID251
-7 + from bbbbbbbbbbbbbbbbbbbbbbbbbbbbbb.bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb import (
-8 +     x,  # keep this  # noqa: TID251
-9 + )
-  |
diff --git a/crates/ruff_linter/src/rules/isort/snapshots/ruff_linter__rules__isort__tests__preview__fit_line_length_pragma.py.snap b/crates/ruff_linter/src/rules/isort/snapshots/ruff_linter__rules__isort__tests__preview__fit_line_length_pragma.py.snap
deleted file mode 100644
index 5bc4f7f090..0000000000
--- a/crates/ruff_linter/src/rules/isort/snapshots/ruff_linter__rules__isort__tests__preview__fit_line_length_pragma.py.snap
+++ /dev/null
@@ -1,25 +0,0 @@
----
-source: crates/ruff_linter/src/rules/isort/mod.rs
----
-I001 [*] Import block is un-sorted or un-formatted
- --> fit_line_length_pragma.py:3:1
-  |
-1 |   # The next import fits on one line once the pragma comment is excluded from the width;
-2 |   # in preview it should not be wrapped (the `# noqa` must stay effective).
-3 | / from aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa.aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa import x  # noqa: TID251
-4 | | # The next import exceeds the line length even without the pragma comment;
-5 | | # it must still be wrapped.
-6 | | from bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb.bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb import x  # noqa: TID251
-  | |_________________________________________________________________________________________^
-help: Organize imports
-   |
-3  | from aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa.aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa import x  # noqa: TID251
-4  +
-5  | # The next import exceeds the line length even without the pragma comment;
-6  | # it must still be wrapped.
-   - from bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb.bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb import x  # noqa: TID251
-7  + from bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb.bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb import (
-8  +     x,  # noqa: TID251
-9  + )
-10 |
-   |
diff --git a/crates/ruff_linter/src/rules/pycodestyle/mod.rs b/crates/ruff_linter/src/rules/pycodestyle/mod.rs
index 785eca607d..8ead50bc96 100644
--- a/crates/ruff_linter/src/rules/pycodestyle/mod.rs
+++ b/crates/ruff_linter/src/rules/pycodestyle/mod.rs
@@ -38,6 +38,7 @@ mod tests {
     #[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::LineTooLong, Path::new("E501_5.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"))]
@@ -75,7 +76,6 @@ mod tests {
         Ok(())
     }
 
-    #[test_case(Rule::LineTooLong, Path::new("E501_5.py"))]
     #[test_case(Rule::ModuleImportNotAtTopOfFile, Path::new("E40.py"))]
     #[test_case(Rule::ModuleImportNotAtTopOfFile, Path::new("E402_0.py"))]
     #[test_case(Rule::ModuleImportNotAtTopOfFile, Path::new("E402_1.py"))]
diff --git a/crates/ruff_linter/src/rules/pycodestyle/overlong.rs b/crates/ruff_linter/src/rules/pycodestyle/overlong.rs
index 80092565b1..6c2ef705b2 100644
--- a/crates/ruff_linter/src/rules/pycodestyle/overlong.rs
+++ b/crates/ruff_linter/src/rules/pycodestyle/overlong.rs
@@ -1,11 +1,10 @@
 use std::ops::Deref;
 
-use ruff_python_trivia::CommentRanges;
+use ruff_python_trivia::{CommentRanges, find_trailing_pragma_offset};
 use ruff_source_file::Line;
 use ruff_text_size::{TextLen, TextRange};
 
-use crate::line_width::{IndentWidth, LineLength, LineWidthBuilder, pragma_offset_for_line_length};
-use crate::settings::types::PreviewMode;
+use crate::line_width::{IndentWidth, LineLength, LineWidthBuilder};
 
 #[derive(Debug)]
 pub(super) struct Overlong {
@@ -22,7 +21,6 @@ impl Overlong {
         limit: LineLength,
         task_tags: &[String],
         tab_size: IndentWidth,
-        preview: PreviewMode,
     ) -> Option<Self> {
         // The maximum width of the line is the number of bytes multiplied by the tab size (the
         // worst-case scenario is that the line is all tabs). If the maximum width is less than the
@@ -39,7 +37,7 @@ impl Overlong {
         }
 
         // Strip trailing comments and re-measure the line, if needed.
-        let line = StrippedLine::from_line(line, comment_ranges, task_tags, preview);
+        let line = StrippedLine::from_line(line, comment_ranges, task_tags);
         let width = match &line {
             StrippedLine::WithoutPragma(line) => {
                 let width = measure(line.as_str(), tab_size);
@@ -118,12 +116,7 @@ enum StrippedLine<'a> {
 impl<'a> StrippedLine<'a> {
     /// Strip trailing comments from a [`Line`], if the line ends with a pragma comment (like
     /// `# type: ignore`) or, if necessary, a task comment (like `# TODO`).
-    fn from_line(
-        line: &'a Line<'a>,
-        comment_ranges: &CommentRanges,
-        task_tags: &[String],
-        preview: PreviewMode,
-    ) -> Self {
+    fn from_line(line: &'a Line<'a>, comment_ranges: &CommentRanges, task_tags: &[String]) -> Self {
         let [comment_range] = comment_ranges.comments_in_range(line.range()) else {
             return Self::Unchanged(line);
         };
@@ -132,8 +125,8 @@ impl<'a> StrippedLine<'a> {
         let comment_range = comment_range - line.start();
         let comment = &line.as_str()[comment_range];
 
-        // Ex) `# type: ignore` or (in preview) `# some comment # noqa: F401`
-        if let Some(offset) = pragma_offset_for_line_length(comment, preview) {
+        // Ex) `# type: ignore` or `# some comment # noqa: F401`
+        if let Some(offset) = find_trailing_pragma_offset(comment) {
             // Strip the pragma from the line, preserving any preceding non-pragma comment text.
             let pragma_start = usize::from(comment_range.start()) + offset;
             let prefix = line[..pragma_start].trim_end();
diff --git a/crates/ruff_linter/src/rules/pycodestyle/rules/doc_line_too_long.rs b/crates/ruff_linter/src/rules/pycodestyle/rules/doc_line_too_long.rs
index afdca7b7e7..a94f5e8a7d 100644
--- a/crates/ruff_linter/src/rules/pycodestyle/rules/doc_line_too_long.rs
+++ b/crates/ruff_linter/src/rules/pycodestyle/rules/doc_line_too_long.rs
@@ -105,7 +105,6 @@ pub(crate) fn doc_line_too_long(
             &[]
         },
         settings.tab_size,
-        settings.preview,
     ) {
         context.report_diagnostic(
             DocLineTooLong(overlong.width(), limit.value() as usize),
diff --git a/crates/ruff_linter/src/rules/pycodestyle/rules/line_too_long.rs b/crates/ruff_linter/src/rules/pycodestyle/rules/line_too_long.rs
index a2d98f1604..1de0ec54b9 100644
--- a/crates/ruff_linter/src/rules/pycodestyle/rules/line_too_long.rs
+++ b/crates/ruff_linter/src/rules/pycodestyle/rules/line_too_long.rs
@@ -101,7 +101,6 @@ pub(crate) fn line_too_long(
             &[]
         },
         settings.tab_size,
-        settings.preview,
     ) {
         context.report_diagnostic(
             LineTooLong(overlong.width(), limit.value() as usize),
diff --git a/crates/ruff_linter/src/rules/pycodestyle/snapshots/ruff_linter__rules__pycodestyle__tests__preview__line-too-long_E501_5.py.snap b/crates/ruff_linter/src/rules/pycodestyle/snapshots/ruff_linter__rules__pycodestyle__tests__line-too-long_E501_5.py.snap
similarity index 100%
rename from crates/ruff_linter/src/rules/pycodestyle/snapshots/ruff_linter__rules__pycodestyle__tests__preview__line-too-long_E501_5.py.snap
rename to crates/ruff_linter/src/rules/pycodestyle/snapshots/ruff_linter__rules__pycodestyle__tests__line-too-long_E501_5.py.snap
diff --git a/crates/ruff_python_formatter/resources/test/fixtures/ruff/trailing_pragma_nested.py b/crates/ruff_python_formatter/resources/test/fixtures/ruff/trailing_pragma_nested.py
index e24810a7e4..b0f499387e 100644
--- a/crates/ruff_python_formatter/resources/test/fixtures/ruff/trailing_pragma_nested.py
+++ b/crates/ruff_python_formatter/resources/test/fixtures/ruff/trailing_pragma_nested.py
@@ -1,5 +1,5 @@
 # Trailing pragma after another comment - the pragma portion should not count
-# toward reserved width in preview mode.
+# toward reserved width.
 
 # The expression is long enough that the formatter would break it if the full
 # comment width were reserved, but short enough to fit if only the non-pragma
@@ -9,9 +9,9 @@ i = ("aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa",)  # comment
 i = ("aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa",)  # comment  # pyright: ignore
 i = ("aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa",)  ## noqa: F401
 
-# Plain pragma (no nested comment) - should behave the same in stable and preview
+# Plain pragma (no nested comment) - should not reserve any width
 i = ("aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa",)  # noqa: F401
 i = ("aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa",)  # type: ignore
 
-# Not a pragma - should reserve full width in both modes
+# Not a pragma - should reserve full width
 i = ("aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa",)  # comment  # not a pragma
diff --git a/crates/ruff_python_formatter/src/comments/format.rs b/crates/ruff_python_formatter/src/comments/format.rs
index 2fa1e5e2e1..a38fe4cb86 100644
--- a/crates/ruff_python_formatter/src/comments/format.rs
+++ b/crates/ruff_python_formatter/src/comments/format.rs
@@ -3,15 +3,14 @@ use std::borrow::Cow;
 use ruff_formatter::{FormatError, FormatOptions, SourceCode, format_args, write};
 use ruff_python_ast::{AnyNodeRef, NodeKind, PySourceType};
 use ruff_python_trivia::{
-    CommentLinePosition, find_trailing_pragma_offset, is_pragma_comment, lines_after,
-    lines_after_ignoring_trivia, lines_before,
+    CommentLinePosition, find_trailing_pragma_offset, lines_after, lines_after_ignoring_trivia,
+    lines_before,
 };
 use ruff_text_size::{Ranged, TextLen, TextRange};
 
 use crate::comments::SourceComment;
 use crate::context::NodeLevel;
 use crate::prelude::*;
-use crate::preview::is_trailing_pragma_in_comment_width_enabled;
 use crate::statement::suite::should_insert_blank_line_after_class_in_stub_file;
 
 /// Formats the leading comments of a node.
@@ -378,18 +377,11 @@ impl Format<PyFormatContext<'_>> for FormatTrailingEndOfLineComment<'_> {
 
         let normalized_comment = normalize_comment(self.comment, source)?;
 
-        // Don't reserve width for pragma comments. In preview, comments
-        // containing a trailing pragma (e.g., `# comment # noqa: F401`) only
-        // reserve width for the non-pragma prefix.
-        let non_pragma_comment_part = if is_trailing_pragma_in_comment_width_enabled(f.context()) {
-            match find_trailing_pragma_offset(&normalized_comment) {
-                Some(offset) => normalized_comment[..offset].trim_end(),
-                None => &normalized_comment,
-            }
-        } else if is_pragma_comment(&normalized_comment) {
-            ""
-        } else {
-            &normalized_comment
+        // Don't reserve width for pragma comments. Comments containing a trailing pragma
+        // (e.g., `# comment # noqa: F401`) only reserve width for the non-pragma prefix.
+        let non_pragma_comment_part = match find_trailing_pragma_offset(&normalized_comment) {
+            Some(offset) => normalized_comment[..offset].trim_end(),
+            None => &normalized_comment,
         };
 
         let reserved_width = if non_pragma_comment_part.is_empty() {
diff --git a/crates/ruff_python_formatter/src/preview.rs b/crates/ruff_python_formatter/src/preview.rs
index 8a195d5b76..958e1b4cd1 100644
--- a/crates/ruff_python_formatter/src/preview.rs
+++ b/crates/ruff_python_formatter/src/preview.rs
@@ -20,13 +20,3 @@ pub(crate) const fn is_hug_parens_with_braces_and_square_brackets_enabled(
 pub(crate) const fn is_fluent_layout_split_first_call_enabled(context: &PyFormatContext) -> bool {
     context.is_preview()
 }
-
-/// Returns `true` if the
-/// [trailing pragma width handling in comments](https://github.com/astral-sh/ruff/pull/24071)
-/// is enabled.
-/// When enabled, comments like `# text # noqa: F401` only reserve width for
-/// the non-pragma prefix (`# text`), not the trailing pragma.
-/// Make sure to stabilize the corresponding linter preview behavior when stabilizing this preview style.
-pub(crate) const fn is_trailing_pragma_in_comment_width_enabled(context: &PyFormatContext) -> bool {
-    context.is_preview()
-}
diff --git a/crates/ruff_python_formatter/tests/snapshots/format@trailing_pragma_nested.py.snap b/crates/ruff_python_formatter/tests/snapshots/format@trailing_pragma_nested.py.snap
index 05d9669b50..c18d04d6fe 100644
--- a/crates/ruff_python_formatter/tests/snapshots/format@trailing_pragma_nested.py.snap
+++ b/crates/ruff_python_formatter/tests/snapshots/format@trailing_pragma_nested.py.snap
@@ -5,7 +5,7 @@ input_file: crates/ruff_python_formatter/resources/test/fixtures/ruff/trailing_p
 ## Input
 ```python
 # Trailing pragma after another comment - the pragma portion should not count
-# toward reserved width in preview mode.
+# toward reserved width.
 
 # The expression is long enough that the formatter would break it if the full
 # comment width were reserved, but short enough to fit if only the non-pragma
@@ -15,65 +15,33 @@ i = ("aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa",)  # comment
 i = ("aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa",)  # comment  # pyright: ignore
 i = ("aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa",)  ## noqa: F401
 
-# Plain pragma (no nested comment) - should behave the same in stable and preview
+# Plain pragma (no nested comment) - should not reserve any width
 i = ("aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa",)  # noqa: F401
 i = ("aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa",)  # type: ignore
 
-# Not a pragma - should reserve full width in both modes
+# Not a pragma - should reserve full width
 i = ("aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa",)  # comment  # not a pragma
 ```
 
 ## Output
 ```python
 # Trailing pragma after another comment - the pragma portion should not count
-# toward reserved width in preview mode.
+# toward reserved width.
 
 # The expression is long enough that the formatter would break it if the full
 # comment width were reserved, but short enough to fit if only the non-pragma
 # prefix is reserved.
-i = (
-    "aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa",
-)  # comment  # noqa: F401
-i = (
-    "aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa",
-)  # comment  # type: ignore
-i = (
-    "aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa",
-)  # comment  # pyright: ignore
+i = ("aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa",)  # comment  # noqa: F401
+i = ("aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa",)  # comment  # type: ignore
+i = ("aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa",)  # comment  # pyright: ignore
 i = ("aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa",)  ## noqa: F401
 
-# Plain pragma (no nested comment) - should behave the same in stable and preview
+# Plain pragma (no nested comment) - should not reserve any width
 i = ("aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa",)  # noqa: F401
 i = ("aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa",)  # type: ignore
 
-# Not a pragma - should reserve full width in both modes
+# Not a pragma - should reserve full width
 i = (
     "aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa",
 )  # comment  # not a pragma
 ```
-
-
-## Preview changes
-```diff
---- Stable
-+++ Preview
-@@ -4,15 +4,9 @@
- # The expression is long enough that the formatter would break it if the full
- # comment width were reserved, but short enough to fit if only the non-pragma
- # prefix is reserved.
--i = (
--    "aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa",
--)  # comment  # noqa: F401
--i = (
--    "aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa",
--)  # comment  # type: ignore
--i = (
--    "aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa",
--)  # comment  # pyright: ignore
-+i = ("aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa",)  # comment  # noqa: F401
-+i = ("aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa",)  # comment  # type: ignore
-+i = ("aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa",)  # comment  # pyright: ignore
- i = ("aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa",)  ## noqa: F401
- 
- # Plain pragma (no nested comment) - should behave the same in stable and preview
-```
diff --git a/docs/formatter/black.md b/docs/formatter/black.md
index b8520cd5e5..7b160a0e07 100644
--- a/docs/formatter/black.md
+++ b/docs/formatter/black.md
@@ -39,6 +39,8 @@ has already been formatted by Black.
 ### Pragma comments are ignored when computing line width
 
 Pragma comments (`# type`, `# noqa`, `# pyright`, `# pylint`, etc.) are ignored when computing the width of a line.
+For mixed comments such as `# explanation  # noqa: F401`, only the pragma suffix is ignored;
+the preceding comment text still contributes to the line width.
 This prevents Ruff from moving pragma comments around, thereby modifying their meaning and behavior:
 
 See Ruff's [pragma comment handling proposal](https://github.com/astral-sh/ruff/discussions/6670)