From 4fb242e4bfc455cd24d372f2fbe8a507b9953488 Mon Sep 17 00:00:00 2001
From: A4-Tacks <wdsjxhno1001@163.com>
Date: Sun, 16 Nov 2025 17:23:32 +0800
Subject: [PATCH] Fix make::unnamed_param result a untyped_param

- Add `make::untyped_param`
- Add some basic make tests

Example
---
```rust
make::unnamed_param(make::ty("Vec<T>")),

```

**Before this PR**

```text
PARAM@0..4
  IDENT_PAT@0..4
    NAME@0..4
      IDENT@0..4 "Vec"
```

**After this PR**

```text
PARAM@0..6
  PATH_TYPE@0..6
    PATH@0..6
      PATH_SEGMENT@0..6
        NAME_REF@0..3
          IDENT@0..3 "Vec"
        GENERIC_ARG_LIST@3..6
          L_ANGLE@3..4 "<"
          TYPE_ARG@4..5
            PATH_TYPE@4..5
              PATH@4..5
                PATH_SEGMENT@4..5
                  NAME_REF@4..5
                    IDENT@4..5 "T"
          R_ANGLE@5..6 ">"
```

---

Assist: `Generate a type alias for function with unnamed params`

```rust
fn foo$0(x: Vec<i32>) {}
```

**Before this PR**

```rust
type FooFn = fn(Vec);

fn foo(x: Vec<i32>) {}
```

**After this PR**

```rust
type FooFn = fn(Vec<i32>);

fn foo(x: Vec<i32>) {}
```
---
 crates/syntax/src/ast/make.rs | 97 ++++++++++++++++++++++++++++++++++-
 1 file changed, 96 insertions(+), 1 deletion(-)

diff --git a/crates/syntax/src/ast/make.rs b/crates/syntax/src/ast/make.rs
index dba39204e3..4a7afed61e 100644
--- a/crates/syntax/src/ast/make.rs
+++ b/crates/syntax/src/ast/make.rs
@@ -1016,7 +1016,19 @@ pub fn item_static(
 }
 
 pub fn unnamed_param(ty: ast::Type) -> ast::Param {
-    ast_from_text(&format!("fn f({ty}) {{ }}"))
+    quote! {
+        Param {
+            #ty
+        }
+    }
+}
+
+pub fn untyped_param(pat: ast::Pat) -> ast::Param {
+    quote! {
+        Param {
+            #pat
+        }
+    }
 }
 
 pub fn param(pat: ast::Pat, ty: ast::Type) -> ast::Param {
@@ -1456,3 +1468,86 @@ pub mod tokens {
         }
     }
 }
+
+#[cfg(test)]
+mod tests {
+    use expect_test::expect;
+
+    use super::*;
+
+    #[track_caller]
+    fn check(node: impl AstNode, expect: expect_test::Expect) {
+        let node_debug = format!("{:#?}", node.syntax());
+        expect.assert_eq(&node_debug);
+    }
+
+    #[test]
+    fn test_unnamed_param() {
+        check(
+            unnamed_param(ty("Vec")),
+            expect![[r#"
+                PARAM@0..3
+                  PATH_TYPE@0..3
+                    PATH@0..3
+                      PATH_SEGMENT@0..3
+                        NAME_REF@0..3
+                          IDENT@0..3 "Vec"
+            "#]],
+        );
+
+        check(
+            unnamed_param(ty("Vec<T>")),
+            expect![[r#"
+                PARAM@0..6
+                  PATH_TYPE@0..6
+                    PATH@0..6
+                      PATH_SEGMENT@0..6
+                        NAME_REF@0..3
+                          IDENT@0..3 "Vec"
+                        GENERIC_ARG_LIST@3..6
+                          L_ANGLE@3..4 "<"
+                          TYPE_ARG@4..5
+                            PATH_TYPE@4..5
+                              PATH@4..5
+                                PATH_SEGMENT@4..5
+                                  NAME_REF@4..5
+                                    IDENT@4..5 "T"
+                          R_ANGLE@5..6 ">"
+            "#]],
+        );
+    }
+
+    #[test]
+    fn test_untyped_param() {
+        check(
+            untyped_param(path_pat(ext::ident_path("name"))),
+            expect![[r#"
+                PARAM@0..4
+                  IDENT_PAT@0..4
+                    NAME@0..4
+                      IDENT@0..4 "name"
+            "#]],
+        );
+
+        check(
+            untyped_param(
+                range_pat(
+                    Some(path_pat(ext::ident_path("start"))),
+                    Some(path_pat(ext::ident_path("end"))),
+                )
+                .into(),
+            ),
+            expect![[r#"
+                PARAM@0..10
+                  RANGE_PAT@0..10
+                    IDENT_PAT@0..5
+                      NAME@0..5
+                        IDENT@0..5 "start"
+                    DOT2@5..7 ".."
+                    IDENT_PAT@7..10
+                      NAME@7..10
+                        IDENT@7..10 "end"
+            "#]],
+        );
+    }
+}