Repository: rust-lang/rustfmt (rust)

Issue:
Rustfmt wrongly alphabatizes raw identifiers in `use` statements
# Description

I'm writing a toy compiler, and recently split up the elements of my grammar into their own modules.
Unfortunately, there's overlap between the elements and some Rust keywords, so sometimes I need to use raw identifiers:
```
use self::r#enum::*;
use self::interface::*;
use self::struct::*;
```
I would expect these to be sorted alphabetically, _not including the `r#`_
But, rustfmt seems to include it when sorting, and changes this to:
```
use self::interface::*;
use self::r#enum::*;
use self::struct::*;
```

Note that this _doesn't_ happen with modules:
```
mod r#enum;
mod interface;
mod struct;
```
here rustfmt correctly ignores the `r#` prefix when sorting.

I'm open to fixing this, if someone could point me in the right direction! Since it *seems* \*crosses fingers\* like an easy fix.

# Environment

rustfmt 1.4.38-nightly (e0944922 2022-05-31) on macOS Monterey

Pull request description:
Backport 3795
Backport and version gate the original fix for use statement sorting with raw identifiers (#3795)

Let me know if any additional tests need to be added to this.

Closes #5362 

Patch:
diff --git a/src/imports.rs b/src/imports.rs
index 559ed391..8d41c881 100644
--- a/src/imports.rs
+++ b/src/imports.rs
@@ -15,7 +15,7 @@ use rustc_span::{
 use crate::comment::combine_strs_with_missing_comments;
 use crate::config::lists::*;
 use crate::config::ImportGranularity;
-use crate::config::{Edition, IndentStyle};
+use crate::config::{Edition, IndentStyle, Version};
 use crate::lists::{
     definitive_tactic, itemize_list, write_list, ListFormatting, ListItem, Separator,
 };
@@ -92,7 +92,7 @@ impl<'a> FmtVisitor<'a> {
 
 // FIXME we do a lot of allocation to make our own representation.
 #[derive(Clone, Eq, Hash, PartialEq)]
-pub(crate) enum UseSegment {
+pub(crate) enum UseSegmentKind {
     Ident(String, Option<String>),
     Slf(Option<String>),
     Super(Option<String>),
@@ -101,6 +101,12 @@ pub(crate) enum UseSegment {
     List(Vec<UseTree>),
 }
 
+#[derive(Clone, Eq, PartialEq)]
+pub(crate) struct UseSegment {
+    pub(crate) kind: UseSegmentKind,
+    pub(crate) version: Version,
+}
+
 #[derive(Clone)]
 pub(crate) struct UseTree {
     pub(crate) path: Vec<UseSegment>,
@@ -134,34 +140,38 @@ impl Spanned for UseTree {
 impl UseSegment {
     // Clone a version of self with any top-level alias removed.
     fn remove_alias(&self) -> UseSegment {
-        match *self {
-            UseSegment::Ident(ref s, _) => UseSegment::Ident(s.clone(), None),
-            UseSegment::Slf(_) => UseSegment::Slf(None),
-            UseSegment::Super(_) => UseSegment::Super(None),
-            UseSegment::Crate(_) => UseSegment::Crate(None),
-            _ => self.clone(),
+        let kind = match self.kind {
+            UseSegmentKind::Ident(ref s, _) => UseSegmentKind::Ident(s.clone(), None),
+            UseSegmentKind::Slf(_) => UseSegmentKind::Slf(None),
+            UseSegmentKind::Super(_) => UseSegmentKind::Super(None),
+            UseSegmentKind::Crate(_) => UseSegmentKind::Crate(None),
+            _ => return self.clone(),
+        };
+        UseSegment {
+            kind,
+            version: self.version,
         }
     }
 
     // Check if self == other with their aliases removed.
     fn equal_except_alias(&self, other: &Self) -> bool {
-        match (self, other) {
-            (UseSegment::Ident(ref s1, _), UseSegment::Ident(ref s2, _)) => s1 == s2,
-            (UseSegment::Slf(_), UseSegment::Slf(_))
-            | (UseSegment::Super(_), UseSegment::Super(_))
-            | (UseSegment::Crate(_), UseSegment::Crate(_))
-            | (UseSegment::Glob, UseSegment::Glob) => true,
-            (UseSegment::List(ref list1), UseSegment::List(ref list2)) => list1 == list2,
+        match (&self.kind, &other.kind) {
+            (UseSegmentKind::Ident(ref s1, _), UseSegmentKind::Ident(ref s2, _)) => s1 == s2,
+            (UseSegmentKind::Slf(_), UseSegmentKind::Slf(_))
+            | (UseSegmentKind::Super(_), UseSegmentKind::Super(_))
+            | (UseSegmentKind::Crate(_), UseSegmentKind::Crate(_))
+            | (UseSegmentKind::Glob, UseSegmentKind::Glob) => true,
+            (UseSegmentKind::List(ref list1), UseSegmentKind::List(ref list2)) => list1 == list2,
             _ => false,
         }
     }
 
     fn get_alias(&self) -> Option<&str> {
-        match self {
-            UseSegment::Ident(_, a)
-            | UseSegment::Slf(a)
-            | UseSegment::Super(a)
-            | UseSegment::Crate(a) => a.as_deref(),
+        match &self.kind {
+            UseSegmentKind::Ident(_, a)
+            | UseSegmentKind::Slf(a)
+            | UseSegmentKind::Super(a)
+            | UseSegmentKind::Crate(a) => a.as_deref(),
             _ => None,
         }
     }
@@ -175,19 +185,24 @@ impl UseSegment {
         if name.is_empty() || name == "{{root}}" {
             return None;
         }
-        Some(match name {
-            "self" => UseSegment::Slf(None),
-            "super" => UseSegment::Super(None),
-            "crate" => UseSegment::Crate(None),
+        let kind = match name {
+            "self" => UseSegmentKind::Slf(None),
+            "super" => UseSegmentKind::Super(None),
+            "crate" => UseSegmentKind::Crate(None),
             _ => {
                 let mod_sep = if modsep { "::" } else { "" };
-                UseSegment::Ident(format!("{}{}", mod_sep, name), None)
+                UseSegmentKind::Ident(format!("{}{}", mod_sep, name), None)
             }
+        };
+
+        Some(UseSegment {
+            kind,
+            version: context.config.version(),
         })
     }
 
     fn contains_comment(&self) -> bool {
-        if let UseSegment::List(list) = self {
+        if let UseSegmentKind::List(list) = &self.kind {
             list.iter().any(|subtree| subtree.contains_comment())
         } else {
             false
@@ -254,20 +269,38 @@ impl fmt::Debug for UseTree {
 
 impl fmt::Debug for UseSegment {
     fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
-        fmt::Display::fmt(self, f)
+        fmt::Display::fmt(&self.kind, f)
     }
 }
 
 impl fmt::Display for UseSegment {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        fmt::Display::fmt(&self.kind, f)
+    }
+}
+
+impl Hash for UseSegment {
+    fn hash<H: Hasher>(&self, state: &mut H) {
+        self.kind.hash(state);
+    }
+}
+
+impl fmt::Debug for UseSegmentKind {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        fmt::Display::fmt(self, f)
+    }
+}
+
+impl fmt::Display for UseSegmentKind {
     fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
         match *self {
-            UseSegment::Glob => write!(f, "*"),
-            UseSegment::Ident(ref s, Some(ref alias)) => write!(f, "{} as {}", s, alias),
-            UseSegment::Ident(ref s, None) => write!(f, "{}", s),
-            UseSegment::Slf(..) => write!(f, "self"),
-            UseSegment::Super(..) => write!(f, "super"),
-            UseSegment::Crate(..) => write!(f, "crate"),
-            UseSegment::List(ref list) => {
+            UseSegmentKind::Glob => write!(f, "*"),
+            UseSegmentKind::Ident(ref s, Some(ref alias)) => write!(f, "{} as {}", s, alias),
+            UseSegmentKind::Ident(ref s, None) => write!(f, "{}", s),
+            UseSegmentKind::Slf(..) => write!(f, "self"),
+            UseSegmentKind::Super(..) => write!(f, "super"),
+            UseSegmentKind::Crate(..) => write!(f, "crate"),
+            UseSegmentKind::List(ref list) => {
                 write!(f, "{{")?;
                 for (i, item) in list.iter().enumerate() {
                     if i != 0 {
@@ -411,13 +444,19 @@ impl UseTree {
             }
         }
 
+        let version = context.config.version();
+
         match a.kind {
             UseTreeKind::Glob => {
                 // in case of a global path and the glob starts at the root, e.g., "::*"
                 if a.prefix.segments.len() == 1 && leading_modsep {
-                    result.path.push(UseSegment::Ident("".to_owned(), None));
+                    let kind = UseSegmentKind::Ident("".to_owned(), None);
+                    result.path.push(UseSegment { kind, version });
                 }
-                result.path.push(UseSegment::Glob);
+                result.path.push(UseSegment {
+                    kind: UseSegmentKind::Glob,
+                    version,
+                });
             }
             UseTreeKind::Nested(ref list) => {
                 // Extract comments between nested use items.
@@ -438,16 +477,18 @@ impl UseTree {
                 // in case of a global path and the nested list starts at the root,
                 // e.g., "::{foo, bar}"
                 if a.prefix.segments.len() == 1 && leading_modsep {
-                    result.path.push(UseSegment::Ident("".to_owned(), None));
+                    let kind = UseSegmentKind::Ident("".to_owned(), None);
+                    result.path.push(UseSegment { kind, version });
                 }
-                result.path.push(UseSegment::List(
+                let kind = UseSegmentKind::List(
                     list.iter()
                         .zip(items)
                         .map(|(t, list_item)| {
                             Self::from_ast(context, &t.0, Some(list_item), None, None, None)
                         })
                         .collect(),
-                ));
+                );
+                result.path.push(UseSegment { kind, version });
             }
             UseTreeKind::Simple(ref rename, ..) => {
                 // If the path has leading double colons and is composed of only 2 segments, then we
@@ -469,13 +510,15 @@ impl UseTree {
                         Some(rewrite_ident(context, ident).to_owned())
                     }
                 });
-                let segment = match name.as_ref() {
-                    "self" => UseSegment::Slf(alias),
-                    "super" => UseSegment::Super(alias),
-                    "crate" => UseSegment::Crate(alias),
-                    _ => UseSegment::Ident(name, alias),
+                let kind = match name.as_ref() {
+                    "self" => UseSegmentKind::Slf(alias),
+                    "super" => UseSegmentKind::Super(alias),
+                    "crate" => UseSegmentKind::Crate(alias),
+                    _ => UseSegmentKind::Ident(name, alias),
                 };
 
+                let segment = UseSegment { kind, version };
+
                 // `name` is already in result.
                 result.path.pop();
                 result.path.push(segment);
@@ -492,13 +535,13 @@ impl UseTree {
         let mut aliased_self = false;
 
         // Remove foo::{} or self without attributes.
-        match last {
+        match last.kind {
             _ if self.attrs.is_some() => (),
-            UseSegment::List(ref list) if list.is_empty() => {
+            UseSegmentKind::List(ref list) if list.is_empty() => {
                 self.path = vec![];
                 return self;
             }
-            UseSegment::Slf(None) if self.path.is_empty() && self.visibility.is_some() => {
+            UseSegmentKind::Slf(None) if self.path.is_empty() && self.visibility.is_some() => {
                 self.path = vec![];
                 return self;
             }
@@ -506,15 +549,19 @@ impl UseTree {
         }
 
         // Normalise foo::self -> foo.
-        if let UseSegment::Slf(None) = last {
+        if let UseSegmentKind::Slf(None) = last.kind {
             if !self.path.is_empty() {
                 return self;
             }
         }
 
         // Normalise foo::self as bar -> foo as bar.
-        if let UseSegment::Slf(_) = last {
-            if let Some(UseSegment::Ident(_, None)) = self.path.last() {
+        if let UseSegmentKind::Slf(_) = last.kind {
+            if let Some(UseSegment {
+                kind: UseSegmentKind::Ident(_, None),
+                ..
+            }) = self.path.last()
+            {
                 aliased_self = true;
             }
         }
@@ -522,9 +569,12 @@ impl UseTree {
         let mut done = false;
         if aliased_self {
             match self.path.last_mut() {
-                Some(UseSegment::Ident(_, ref mut old_rename)) => {
+                Some(UseSegment {
+                    kind: UseSegmentKind::Ident(_, ref mut old_rename),
+                    ..
+                }) => {
                     assert!(old_rename.is_none());
-                    if let UseSegment::Slf(Some(rename)) = last.clone() {
+                    if let UseSegmentKind::Slf(Some(rename)) = last.clone().kind {
                         *old_rename = Some(rename);
                         done = true;
                     }
@@ -538,15 +588,15 @@ impl UseTree {
         }
 
         // Normalise foo::{bar} -> foo::bar
-        if let UseSegment::List(ref list) = last {
+        if let UseSegmentKind::List(ref list) = last.kind {
             if list.len() == 1 && list[0].to_string() != "self" {
                 normalize_sole_list = true;
             }
         }
 
         if normalize_sole_list {
-            match last {
-                UseSegment::List(list) => {
+            match last.kind {
+                UseSegmentKind::List(list) => {
                     for seg in &list[0].path {
                         self.path.push(seg.clone());
                     }
@@ -557,10 +607,13 @@ impl UseTree {
         }
 
         // Recursively normalize elements of a list use (including sorting the list).
-        if let UseSegment::List(list) = last {
+        if let UseSegmentKind::List(list) = last.kind {
             let mut list = list.into_iter().map(UseTree::normalize).collect::<Vec<_>>();
             list.sort();
-            last = UseSegment::List(list);
+            last = UseSegment {
+                kind: UseSegmentKind::List(list),
+                version: last.version,
+            };
         }
 
         self.path.push(last);
@@ -620,10 +673,10 @@ impl UseTree {
         if self.path.is_empty() || self.contains_comment() {
             return vec![self];
         }
-        match self.path.clone().last().unwrap() {
-            UseSegment::List(list) => {
+        match &self.path.clone().last().unwrap().kind {
+            UseSegmentKind::List(list) => {
                 if list.len() == 1 && list[0].path.len() == 1 {
-                    if let UseSegment::Slf(..) = list[0].path[0] {
+                    if let UseSegmentKind::Slf(..) = list[0].path[0].kind {
                         return vec![self];
                     };
                 }
@@ -671,12 +724,15 @@ impl UseTree {
 
     /// If this tree ends in `::self`, rewrite it to `::{self}`.
     fn nest_trailing_self(mut self) -> UseTree {
-        if let Some(UseSegment::Slf(..)) = self.path.last() {
+        if let Some(UseSegment {
+            kind: UseSegmentKind::Slf(..),
+            ..
+        }) = self.path.last()
+        {
             let self_segment = self.path.pop().unwrap();
-            self.path.push(UseSegment::List(vec![UseTree::from_path(
-                vec![self_segment],
-                DUMMY_SP,
-            )]));
+            let version = self_segment.version;
+            let kind = UseSegmentKind::List(vec![UseTree::from_path(vec![self_segment], DUMMY_SP)]);
+            self.path.push(UseSegment { kind, version });
         }
         self
     }
@@ -692,7 +748,8 @@ fn merge_rest(
         return None;
     }
     if a.len() != len && b.len() != len {
-        if let UseSegment::List(ref list) = a[len] {
+        let version = a[len].version;
+        if let UseSegmentKind::List(ref list) = a[len].kind {
             let mut list = list.clone();
             merge_use_trees_inner(
                 &mut list,
@@ -700,7 +757,8 @@ fn merge_rest(
                 merge_by,
             );
             let mut new_path = b[..len].to_vec();
-            new_path.push(UseSegment::List(list));
+            let kind = UseSegmentKind::List(list);
+            new_path.push(UseSegment { kind, version });
             return Some(new_path);
         }
     } else if len == 1 {
@@ -709,15 +767,28 @@ fn merge_rest(
         } else {
             (&b[0], &a[1..])
         };
+        let kind = UseSegmentKind::Slf(common.get_alias().map(ToString::to_string));
+        let version = a[0].version;
         let mut list = vec![UseTree::from_path(
-            vec![UseSegment::Slf(common.get_alias().map(ToString::to_string))],
+            vec![UseSegment { kind, version }],
             DUMMY_SP,
         )];
         match rest {
-            [UseSegment::List(rest_list)] => list.extend(rest_list.clone()),
+            [
+                UseSegment {
+                    kind: UseSegmentKind::List(rest_list),
+                    ..
+                },
+            ] => list.extend(rest_list.clone()),
             _ => list.push(UseTree::from_path(rest.to_vec(), DUMMY_SP)),
         }
-        return Some(vec![b[0].clone(), UseSegment::List(list)]);
+        return Some(vec![
+            b[0].clone(),
+            UseSegment {
+                kind: UseSegmentKind::List(list),
+                version,
+            },
+        ]);
     } else {
         len -= 1;
     }
@@ -727,7 +798,9 @@ fn merge_rest(
     ];
     list.sort();
     let mut new_path = b[..len].to_vec();
-    new_path.push(UseSegment::List(list));
+    let kind = UseSegmentKind::List(list);
+    let version = a[0].version;
+    new_path.push(UseSegment { kind, version });
     Some(new_path)
 }
 
@@ -805,19 +878,33 @@ impl PartialOrd for UseTree {
 }
 impl Ord for UseSegment {
     fn cmp(&self, other: &UseSegment) -> Ordering {
-        use self::UseSegment::*;
+        use self::UseSegmentKind::*;
 
         fn is_upper_snake_case(s: &str) -> bool {
             s.chars()
                 .all(|c| c.is_uppercase() || c == '_' || c.is_numeric())
         }
 
-        match (self, other) {
-            (&Slf(ref a), &Slf(ref b))
-            | (&Super(ref a), &Super(ref b))
-            | (&Crate(ref a), &Crate(ref b)) => a.cmp(b),
-            (&Glob, &Glob) => Ordering::Equal,
-            (&Ident(ref ia, ref aa), &Ident(ref ib, ref ab)) => {
+        match (&self.kind, &other.kind) {
+            (Slf(ref a), Slf(ref b))
+            | (Super(ref a), Super(ref b))
+            | (Crate(ref a), Crate(ref b)) => match (a, b) {
+                (Some(sa), Some(sb)) => {
+                    if self.version == Version::Two {
+                        sa.trim_start_matches("r#").cmp(sb.trim_start_matches("r#"))
+                    } else {
+                        a.cmp(b)
+                    }
+                }
+                (_, _) => a.cmp(b),
+            },
+            (Glob, Glob) => Ordering::Equal,
+            (Ident(ref pia, ref aa), Ident(ref pib, ref ab)) => {
+                let (ia, ib) = if self.version == Version::Two {
+                    (pia.trim_start_matches("r#"), pib.trim_start_matches("r#"))
+                } else {
+                    (pia.as_str(), pib.as_str())
+                };
                 // snake_case < CamelCase < UPPER_SNAKE_CASE
                 if ia.starts_with(char::is_uppercase) && ib.starts_with(char::is_lowercase) {
                     return Ordering::Greater;
@@ -835,15 +922,21 @@ impl Ord for UseSegment {
                 if ident_ord != Ordering::Equal {
                     return ident_ord;
                 }
-                if aa.is_none() && ab.is_some() {
-                    return Ordering::Less;
-                }
-                if aa.is_some() && ab.is_none() {
-                    return Ordering::Greater;
+                match (aa, ab) {
+                    (None, Some(_)) => Ordering::Less,
+                    (Some(_), None) => Ordering::Greater,
+                    (Some(aas), Some(abs)) => {
+                        if self.version == Version::Two {
+                            aas.trim_start_matches("r#")
+                                .cmp(abs.trim_start_matches("r#"))
+                        } else {
+                            aas.cmp(abs)
+                        }
+                    }
+                    (None, None) => Ordering::Equal,
                 }
-                aa.cmp(ab)
             }
-            (&List(ref a), &List(ref b)) => {
+            (List(ref a), List(ref b)) => {
                 for (a, b) in a.iter().zip(b.iter()) {
                     let ord = a.cmp(b);
                     if ord != Ordering::Equal {
@@ -853,16 +946,16 @@ impl Ord for UseSegment {
 
                 a.len().cmp(&b.len())
             }
-            (&Slf(_), _) => Ordering::Less,
-            (_, &Slf(_)) => Ordering::Greater,
-            (&Super(_), _) => Ordering::Less,
-            (_, &Super(_)) => Ordering::Greater,
-            (&Crate(_), _) => Ordering::Less,
-            (_, &Crate(_)) => Ordering::Greater,
-            (&Ident(..), _) => Ordering::Less,
-            (_, &Ident(..)) => Ordering::Greater,
-            (&Glob, _) => Ordering::Less,
-            (_, &Glob) => Ordering::Greater,
+            (Slf(_), _) => Ordering::Less,
+            (_, Slf(_)) => Ordering::Greater,
+            (Super(_), _) => Ordering::Less,
+            (_, Super(_)) => Ordering::Greater,
+            (Crate(_), _) => Ordering::Less,
+            (_, Crate(_)) => Ordering::Greater,
+            (Ident(..), _) => Ordering::Less,
+            (_, Ident(..)) => Ordering::Greater,
+            (Glob, _) => Ordering::Less,
+            (_, Glob) => Ordering::Greater,
         }
     }
 }
@@ -906,7 +999,7 @@ fn rewrite_nested_use_tree(
     }
     let has_nested_list = use_tree_list.iter().any(|use_segment| {
         use_segment.path.last().map_or(false, |last_segment| {
-            matches!(last_segment, UseSegment::List(..))
+            matches!(last_segment.kind, UseSegmentKind::List(..))
         })
     });
 
@@ -957,17 +1050,19 @@ fn rewrite_nested_use_tree(
 
 impl Rewrite for UseSegment {
     fn rewrite(&self, context: &RewriteContext<'_>, shape: Shape) -> Option<String> {
-        Some(match self {
-            UseSegment::Ident(ref ident, Some(ref rename)) => format!("{} as {}", ident, rename),
-            UseSegment::Ident(ref ident, None) => ident.clone(),
-            UseSegment::Slf(Some(ref rename)) => format!("self as {}", rename),
-            UseSegment::Slf(None) => "self".to_owned(),
-            UseSegment::Super(Some(ref rename)) => format!("super as {}", rename),
-            UseSegment::Super(None) => "super".to_owned(),
-            UseSegment::Crate(Some(ref rename)) => format!("crate as {}", rename),
-            UseSegment::Crate(None) => "crate".to_owned(),
-            UseSegment::Glob => "*".to_owned(),
-            UseSegment::List(ref use_tree_list) => rewrite_nested_use_tree(
+        Some(match self.kind {
+            UseSegmentKind::Ident(ref ident, Some(ref rename)) => {
+                format!("{} as {}", ident, rename)
+            }
+            UseSegmentKind::Ident(ref ident, None) => ident.clone(),
+            UseSegmentKind::Slf(Some(ref rename)) => format!("self as {}", rename),
+            UseSegmentKind::Slf(None) => "self".to_owned(),
+            UseSegmentKind::Super(Some(ref rename)) => format!("super as {}", rename),
+            UseSegmentKind::Super(None) => "super".to_owned(),
+            UseSegmentKind::Crate(Some(ref rename)) => format!("crate as {}", rename),
+            UseSegmentKind::Crate(None) => "crate".to_owned(),
+            UseSegmentKind::Glob => "*".to_owned(),
+            UseSegmentKind::List(ref use_tree_list) => rewrite_nested_use_tree(
                 context,
                 use_tree_list,
                 // 1 = "{" and "}"
@@ -1016,6 +1111,7 @@ mod test {
 
         struct Parser<'a> {
             input: Peekable<Chars<'a>>,
+            version: Version,
         }
 
         impl<'a> Parser<'a> {
@@ -1028,34 +1124,40 @@ mod test {
             }
 
             fn push_segment(
+                &self,
                 result: &mut Vec<UseSegment>,
                 buf: &mut String,
                 alias_buf: &mut Option<String>,
             ) {
+                let version = self.version;
                 if !buf.is_empty() {
                     let mut alias = None;
                     swap(alias_buf, &mut alias);
 
                     match buf.as_ref() {
                         "self" => {
-                            result.push(UseSegment::Slf(alias));
+                            let kind = UseSegmentKind::Slf(alias);
+                            result.push(UseSegment { kind, version });
                             *buf = String::new();
                             *alias_buf = None;
                         }
                         "super" => {
-                            result.push(UseSegment::Super(alias));
+                            let kind = UseSegmentKind::Super(alias);
+                            result.push(UseSegment { kind, version });
                             *buf = String::new();
                             *alias_buf = None;
                         }
                         "crate" => {
-                            result.push(UseSegment::Crate(alias));
+                            let kind = UseSegmentKind::Crate(alias);
+                            result.push(UseSegment { kind, version });
                             *buf = String::new();
                             *alias_buf = None;
                         }
                         _ => {
                             let mut name = String::new();
                             swap(buf, &mut name);
-                            result.push(UseSegment::Ident(name, alias));
+                            let kind = UseSegmentKind::Ident(name, alias);
+                            result.push(UseSegment { kind, version });
                         }
                     }
                 }
@@ -1070,21 +1172,29 @@ mod test {
                         '{' => {
                             assert!(buf.is_empty());
                             self.bump();
-                            result.push(UseSegment::List(self.parse_list()));
+                            let kind = UseSegmentKind::List(self.parse_list());
+                            result.push(UseSegment {
+                                kind,
+                                version: self.version,
+                            });
                             self.eat('}');
                         }
                         '*' => {
                             assert!(buf.is_empty());
                             self.bump();
-                            result.push(UseSegment::Glob);
+                            let kind = UseSegmentKind::Glob;
+                            result.push(UseSegment {
+                                kind,
+                                version: self.version,
+                            });
                         }
                         ':' => {
                             self.bump();
                             self.eat(':');
-                            Self::push_segment(&mut result, &mut buf, &mut alias_buf);
+                            self.push_segment(&mut result, &mut buf, &mut alias_buf);
                         }
                         '}' | ',' => {
-                            Self::push_segment(&mut result, &mut buf, &mut alias_buf);
+                            self.push_segment(&mut result, &mut buf, &mut alias_buf);
                             return UseTree {
                                 path: result,
                                 span: DUMMY_SP,
@@ -1110,7 +1220,7 @@ mod test {
                         }
                     }
                 }
-                Self::push_segment(&mut result, &mut buf, &mut alias_buf);
+                self.push_segment(&mut result, &mut buf, &mut alias_buf);
                 UseTree {
                     path: result,
                     span: DUMMY_SP,
@@ -1136,6 +1246,7 @@ mod test {
 
         let mut parser = Parser {
             input: s.chars().peekable(),
+            version: Version::One,
         };
         parser.parse_in_list()
     }
diff --git a/src/reorder.rs b/src/reorder.rs
index 8ae297de..9e4a668a 100644
--- a/src/reorder.rs
+++ b/src/reorder.rs
@@ -12,7 +12,7 @@ use rustc_ast::ast;
 use rustc_span::{symbol::sym, Span};
 
 use crate::config::{Config, GroupImportsTactic};
-use crate::imports::{normalize_use_trees_with_granularity, UseSegment, UseTree};
+use crate::imports::{normalize_use_trees_with_granularity, UseSegmentKind, UseTree};
 use crate::items::{is_mod_decl, rewrite_extern_crate, rewrite_mod};
 use crate::lists::{itemize_list, write_list, ListFormatting, ListItem};
 use crate::rewrite::RewriteContext;
@@ -182,16 +182,16 @@ fn group_imports(uts: Vec<UseTree>) -> Vec<Vec<UseTree>> {
             external_imports.push(ut);
             continue;
         }
-        match &ut.path[0] {
-            UseSegment::Ident(id, _) => match id.as_ref() {
+        match &ut.path[0].kind {
+            UseSegmentKind::Ident(id, _) => match id.as_ref() {
                 "std" | "alloc" | "core" => std_imports.push(ut),
                 _ => external_imports.push(ut),
             },
-            UseSegment::Slf(_) | UseSegment::Super(_) | UseSegment::Crate(_) => {
+            UseSegmentKind::Slf(_) | UseSegmentKind::Super(_) | UseSegmentKind::Crate(_) => {
                 local_imports.push(ut)
             }
             // These are probably illegal here
-            UseSegment::Glob | UseSegment::List(_) => external_imports.push(ut),
+            UseSegmentKind::Glob | UseSegmentKind::List(_) => external_imports.push(ut),
         }
     }
 


Test patch:
diff --git a/tests/source/imports_raw_identifiers/version_One.rs b/tests/source/imports_raw_identifiers/version_One.rs
new file mode 100644
index 00000000..bc4b5b13
--- /dev/null
+++ b/tests/source/imports_raw_identifiers/version_One.rs
@@ -0,0 +1,5 @@
+// rustfmt-version:One
+
+use websocket::client::ClientBuilder;
+use websocket::r#async::futures::Stream;
+use websocket::result::WebSocketError;
diff --git a/tests/source/imports_raw_identifiers/version_Two.rs b/tests/source/imports_raw_identifiers/version_Two.rs
new file mode 100644
index 00000000..88e7fbd0
--- /dev/null
+++ b/tests/source/imports_raw_identifiers/version_Two.rs
@@ -0,0 +1,5 @@
+// rustfmt-version:Two
+
+use websocket::client::ClientBuilder;
+use websocket::r#async::futures::Stream;
+use websocket::result::WebSocketError;
diff --git a/tests/target/imports_raw_identifiers/version_One.rs b/tests/target/imports_raw_identifiers/version_One.rs
new file mode 100644
index 00000000..bc4b5b13
--- /dev/null
+++ b/tests/target/imports_raw_identifiers/version_One.rs
@@ -0,0 +1,5 @@
+// rustfmt-version:One
+
+use websocket::client::ClientBuilder;
+use websocket::r#async::futures::Stream;
+use websocket::result::WebSocketError;
diff --git a/tests/target/imports_raw_identifiers/version_Two.rs b/tests/target/imports_raw_identifiers/version_Two.rs
new file mode 100644
index 00000000..22bfe931
--- /dev/null
+++ b/tests/target/imports_raw_identifiers/version_Two.rs
@@ -0,0 +1,5 @@
+// rustfmt-version:Two
+
+use websocket::r#async::futures::Stream;
+use websocket::client::ClientBuilder;
+use websocket::result::WebSocketError;