reorder: use versionsort for use statements

Author: tanriol

rustfmt-core/rustfmt-lib/src/imports.rs

@@ -11,6 +11,7 @@ use crate::config::{Edition, IndentStyle};
 use crate::lists::{
     definitive_tactic, itemize_list, write_list, ListFormatting, ListItem, Separator,
 };
+use crate::reorder::{compare_as_versions, compare_opt_ident_as_versions};
 use crate::rewrite::{Rewrite, RewriteContext};
 use crate::shape::Shape;
 use crate::source_map::SpanUtils;
@@ -677,18 +678,8 @@ impl Ord for UseSegment {
                 if !is_upper_snake_case(ia) && is_upper_snake_case(ib) {
                     return Ordering::Less;
                 }
-                let ident_ord = ia.cmp(ib);
-                if ident_ord != Ordering::Equal {
-                    return ident_ord;
-                }
-                match (aa, ab) {
-                    (None, Some(_)) => Ordering::Less,
-                    (Some(_), None) => Ordering::Greater,
-                    (Some(aas), Some(abs)) => aas
-                        .trim_start_matches("r#")
-                        .cmp(abs.trim_start_matches("r#")),
-                    (None, None) => Ordering::Equal,
-                }
+
+                compare_as_versions(&ia, &ib).then_with(|| compare_opt_ident_as_versions(&aa, &ab))
             }
             (&List(ref a), &List(ref b)) => {
                 for (a, b) in a.iter().zip(b.iter()) {

rustfmt-core/rustfmt-lib/src/reorder.rs

@@ -117,6 +117,26 @@ pub(crate) fn compare_as_versions(left: &str, right: &str) -> Ordering {
     }
 }
 
+/// Compare identifiers, trimming `r#` if present, according to version sort
+pub(crate) fn compare_ident_as_versions(left: &str, right: &str) -> Ordering {
+    compare_as_versions(
+        left.trim_start_matches("r#"),
+        right.trim_start_matches("r#"),
+    )
+}
+
+pub(crate) fn compare_opt_ident_as_versions<S>(left: &Option<S>, right: &Option<S>) -> Ordering
+where
+    S: AsRef<str>,
+{
+    match (left, right) {
+        (None, None) => Ordering::Equal,
+        (None, Some(_)) => Ordering::Less,
+        (Some(_), None) => Ordering::Greater,
+        (Some(left), Some(right)) => compare_ident_as_versions(left.as_ref(), right.as_ref()),
+    }
+}
+
 /// Choose the ordering between the given two items.
 fn compare_items(a: &ast::Item, b: &ast::Item) -> Ordering {
     match (&a.kind, &b.kind) {

rustfmt-core/rustfmt-lib/tests/source/imports-reorder.rs

@@ -3,3 +3,7 @@
 use path::{C,/*A*/ A, B /* B */, self /* self */};
 
 use {ab, ac, aa, Z, b};
+
+// The sort order shall follow versionsort
+use {u8, u128, u64, u16, u32};
+use {v1, v0200, v0030, v0002, v02000, v02001};

rustfmt-core/rustfmt-lib/tests/target/imports-reorder.rs

@@ -3,3 +3,7 @@
 use path::{self /* self */, /* A */ A, B /* B */, C};
 
 use {aa, ab, ac, b, Z};
+
+// The sort order shall follow versionsort
+use {u8, u16, u32, u64, u128};
+use {v0002, v0030, v0200, v02000, v02001, v1};