Merge #10283

10283: minor: simplify generics parsing r=matklad a=matklad

bors r+
🤖

Co-authored-by: Aleksey Kladov <aleksey.kladov@gmail.com>

Author: bors[bot]

crates/parser/src/grammar/generic_args.rs

@@ -32,45 +32,24 @@ fn generic_arg(p: &mut Parser) {
         // fn print_all<T: Iterator<Item, Item::Item, Item::<true>, Item: Display, Item<'a> = Item>>(printables: T) {}
         IDENT if [T![<], T![=], T![:]].contains(&p.nth(1)) => {
             let m = p.start();
-            let path_ty = p.start();
-            let path = p.start();
-            let path_seg = p.start();
             name_ref(p);
             opt_generic_arg_list(p, false);
             match p.current() {
                 // NameRef<...> =
                 T![=] => {
                     p.bump_any();
                     types::type_(p);
-
-                    path_seg.abandon(p);
-                    path.abandon(p);
-                    path_ty.abandon(p);
                     m.complete(p, ASSOC_TYPE_ARG);
                 }
-                T![:] if p.at(T![::]) => {
-                    // NameRef::, this is a path type
-                    path_seg.complete(p, PATH_SEGMENT);
-                    let qual = path.complete(p, PATH);
-                    paths::type_path_for_qualifier(p, qual);
-                    path_ty.complete(p, PATH_TYPE);
-                    m.complete(p, TYPE_ARG);
-                }
                 // NameRef<...>:
-                T![:] => {
+                T![:] if !p.at(T![::]) => {
                     generic_params::bounds(p);
-
-                    path_seg.abandon(p);
-                    path.abandon(p);
-                    path_ty.abandon(p);
                     m.complete(p, ASSOC_TYPE_ARG);
                 }
-                // NameRef, this is a single segment path type
                 _ => {
-                    path_seg.complete(p, PATH_SEGMENT);
-                    path.complete(p, PATH);
-                    path_ty.complete(p, PATH_TYPE);
-                    m.complete(p, TYPE_ARG);
+                    let m = m.complete(p, PATH_SEGMENT).precede(p).complete(p, PATH);
+                    let m = paths::type_path_for_qualifier(p, m);
+                    m.precede(p).complete(p, TYPE_ARG);
                 }
             }
         }

crates/parser/src/grammar/paths.rs

@@ -27,7 +27,7 @@ pub(super) fn expr_path(p: &mut Parser) {
     path(p, Mode::Expr)
 }
 
-pub(crate) fn type_path_for_qualifier(p: &mut Parser, qual: CompletedMarker) {
+pub(crate) fn type_path_for_qualifier(p: &mut Parser, qual: CompletedMarker) -> CompletedMarker {
     path_for_qualifier(p, Mode::Type, qual)
 }
 
@@ -42,10 +42,10 @@ fn path(p: &mut Parser, mode: Mode) {
     let path = p.start();
     path_segment(p, mode, true);
     let qual = path.complete(p, PATH);
-    path_for_qualifier(p, mode, qual)
+    path_for_qualifier(p, mode, qual);
 }
 
-fn path_for_qualifier(p: &mut Parser, mode: Mode, mut qual: CompletedMarker) {
+fn path_for_qualifier(p: &mut Parser, mode: Mode, mut qual: CompletedMarker) -> CompletedMarker {
     loop {
         let use_tree = matches!(p.nth(2), T![*] | T!['{']);
         if p.at(T![::]) && !use_tree {
@@ -55,7 +55,7 @@ fn path_for_qualifier(p: &mut Parser, mode: Mode, mut qual: CompletedMarker) {
             let path = path.complete(p, PATH);
             qual = path;
         } else {
-            break;
+            return qual;
         }
     }
 }