Fix dropped union expressions for piped non-types in PYI055 autofix (#9161)

## Summary

Fix dropped union expressions for piped non-types in `PYI055` autofix

If you had `type[int] | type[str] | str`, it would have dropped the
`str`, which breaks the type!

Closes #9156 

## Test Plan

`cargo test`

crates/ruff_linter/resources/test/fixtures/flake8_pyi/PYI055.py

@@ -37,3 +37,28 @@ def func():
 
     # PYI055
     x: Union[type[requests_mock.Mocker], type[httpretty], type[str]] = requests_mock.Mocker
+
+
+def convert_union(union: UnionType) -> _T | None:
+    converters: tuple[
+        type[_T] | type[Converter[_T]] | Converter[_T] | Callable[[str], _T], ...  # PYI055
+    ] = union.__args__
+    ...
+
+def convert_union(union: UnionType) -> _T | None:
+    converters: tuple[
+        Union[type[_T] | type[Converter[_T]] | Converter[_T] | Callable[[str], _T]], ...  # PYI055
+    ] = union.__args__
+    ...
+
+def convert_union(union: UnionType) -> _T | None:
+    converters: tuple[
+        Union[type[_T] | type[Converter[_T]]] | Converter[_T] | Callable[[str], _T], ...  # PYI055
+    ] = union.__args__
+    ...
+
+def convert_union(union: UnionType) -> _T | None:
+    converters: tuple[
+        Union[type[_T] | type[Converter[_T]] | str] | Converter[_T] | Callable[[str], _T], ...  # PYI055
+    ] = union.__args__
+    ...

crates/ruff_linter/src/rules/flake8_pyi/rules/unnecessary_type_union.rs

@@ -80,17 +80,24 @@ pub(crate) fn unnecessary_type_union<'a>(checker: &mut Checker, union: &'a Expr)
     }
 
     let mut type_exprs = Vec::new();
+    let mut other_exprs = Vec::new();
 
     let mut collect_type_exprs = |expr: &'a Expr, _| {
-        let Some(subscript) = expr.as_subscript_expr() else {
+        let subscript = expr.as_subscript_expr();
-            return;
+
-        };
+        if subscript.is_none() {
+            other_exprs.push(expr);
+        } else {
+            let unwrapped = subscript.unwrap();
             if checker
                 .semantic()
-            .resolve_call_path(subscript.value.as_ref())
+                .resolve_call_path(unwrapped.value.as_ref())
                 .is_some_and(|call_path| matches!(call_path.as_slice(), ["" | "builtins", "type"]))
             {
-            type_exprs.push(&subscript.slice);
+                type_exprs.push(&unwrapped.slice);
+            } else {
+                other_exprs.push(expr);
+            }
         }
     };
 
@@ -113,9 +120,7 @@ pub(crate) fn unnecessary_type_union<'a>(checker: &mut Checker, union: &'a Expr)
 
         if checker.semantic().is_builtin("type") {
             let content = if let Some(subscript) = subscript {
-                checker
+                let types = &Expr::Subscript(ast::ExprSubscript {
-                    .generator()
-                    .expr(&Expr::Subscript(ast::ExprSubscript {
                     value: Box::new(Expr::Name(ast::ExprName {
                         id: "type".into(),
                         ctx: ExprContext::Load,
@@ -142,11 +147,30 @@ pub(crate) fn unnecessary_type_union<'a>(checker: &mut Checker, union: &'a Expr)
                     })),
                     ctx: ExprContext::Load,
                     range: TextRange::default(),
-                    }))
+                });
+
+                if other_exprs.is_empty() {
+                    checker.generator().expr(types)
                 } else {
-                checker
+                    let mut exprs = Vec::new();
-                    .generator()
+                    exprs.push(types);
-                    .expr(&Expr::Subscript(ast::ExprSubscript {
+                    exprs.extend(other_exprs);
+
+                    let union = Expr::Subscript(ast::ExprSubscript {
+                        value: subscript.value.clone(),
+                        slice: Box::new(Expr::Tuple(ast::ExprTuple {
+                            elts: exprs.into_iter().cloned().collect(),
+                            ctx: ExprContext::Load,
+                            range: TextRange::default(),
+                        })),
+                        ctx: ExprContext::Load,
+                        range: TextRange::default(),
+                    });
+
+                    checker.generator().expr(&union)
+                }
+            } else {
+                let types = &Expr::Subscript(ast::ExprSubscript {
                     value: Box::new(Expr::Name(ast::ExprName {
                         id: "type".into(),
                         ctx: ExprContext::Load,
@@ -161,7 +185,17 @@ pub(crate) fn unnecessary_type_union<'a>(checker: &mut Checker, union: &'a Expr)
                     )),
                     ctx: ExprContext::Load,
                     range: TextRange::default(),
-                    }))
+                });
+
+                if other_exprs.is_empty() {
+                    checker.generator().expr(types)
+                } else {
+                    let mut exprs = Vec::new();
+                    exprs.push(types);
+                    exprs.extend(other_exprs);
+
+                    checker.generator().expr(&concatenate_bin_ors(exprs))
+                }
             };
 
             diagnostic.set_fix(Fix::safe_edit(Edit::range_replacement(

crates/ruff_linter/src/rules/flake8_pyi/snapshots/ruff_linter__rules__flake8_pyi__tests__PYI055_PYI055.py.snap

@@ -54,5 +54,91 @@ PYI055.py:39:8: PYI055 [*] Multiple `type` members in a union. Combine them into
 38 38 |     # PYI055
 39    |-    x: Union[type[requests_mock.Mocker], type[httpretty], type[str]] = requests_mock.Mocker
    39 |+    x: type[Union[requests_mock.Mocker, httpretty, str]] = requests_mock.Mocker
+40 40 | 
+41 41 | 
+42 42 | def convert_union(union: UnionType) -> _T | None:
+
+PYI055.py:44:9: PYI055 [*] Multiple `type` members in a union. Combine them into one, e.g., `type[_T | Converter[_T]]`.
+   |
+42 | def convert_union(union: UnionType) -> _T | None:
+43 |     converters: tuple[
+44 |         type[_T] | type[Converter[_T]] | Converter[_T] | Callable[[str], _T], ...  # PYI055
+   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ PYI055
+45 |     ] = union.__args__
+46 |     ...
+   |
+   = help: Combine multiple `type` members
+
+ℹ Safe fix
+41 41 | 
+42 42 | def convert_union(union: UnionType) -> _T | None:
+43 43 |     converters: tuple[
+44    |-        type[_T] | type[Converter[_T]] | Converter[_T] | Callable[[str], _T], ...  # PYI055
+   44 |+        type[_T | Converter[_T]] | Converter[_T] | Callable[[str], _T], ...  # PYI055
+45 45 |     ] = union.__args__
+46 46 |     ...
+47 47 | 
+
+PYI055.py:50:15: PYI055 [*] Multiple `type` members in a union. Combine them into one, e.g., `type[_T | Converter[_T]]`.
+   |
+48 | def convert_union(union: UnionType) -> _T | None:
+49 |     converters: tuple[
+50 |         Union[type[_T] | type[Converter[_T]] | Converter[_T] | Callable[[str], _T]], ...  # PYI055
+   |               ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ PYI055
+51 |     ] = union.__args__
+52 |     ...
+   |
+   = help: Combine multiple `type` members
+
+ℹ Safe fix
+47 47 | 
+48 48 | def convert_union(union: UnionType) -> _T | None:
+49 49 |     converters: tuple[
+50    |-        Union[type[_T] | type[Converter[_T]] | Converter[_T] | Callable[[str], _T]], ...  # PYI055
+   50 |+        Union[type[_T | Converter[_T]] | Converter[_T] | Callable[[str], _T]], ...  # PYI055
+51 51 |     ] = union.__args__
+52 52 |     ...
+53 53 | 
+
+PYI055.py:56:15: PYI055 [*] Multiple `type` members in a union. Combine them into one, e.g., `type[_T | Converter[_T]]`.
+   |
+54 | def convert_union(union: UnionType) -> _T | None:
+55 |     converters: tuple[
+56 |         Union[type[_T] | type[Converter[_T]]] | Converter[_T] | Callable[[str], _T], ...  # PYI055
+   |               ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ PYI055
+57 |     ] = union.__args__
+58 |     ...
+   |
+   = help: Combine multiple `type` members
+
+ℹ Safe fix
+53 53 | 
+54 54 | def convert_union(union: UnionType) -> _T | None:
+55 55 |     converters: tuple[
+56    |-        Union[type[_T] | type[Converter[_T]]] | Converter[_T] | Callable[[str], _T], ...  # PYI055
+   56 |+        Union[type[_T | Converter[_T]]] | Converter[_T] | Callable[[str], _T], ...  # PYI055
+57 57 |     ] = union.__args__
+58 58 |     ...
+59 59 | 
+
+PYI055.py:62:15: PYI055 [*] Multiple `type` members in a union. Combine them into one, e.g., `type[_T | Converter[_T]]`.
+   |
+60 | def convert_union(union: UnionType) -> _T | None:
+61 |     converters: tuple[
+62 |         Union[type[_T] | type[Converter[_T]] | str] | Converter[_T] | Callable[[str], _T], ...  # PYI055
+   |               ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ PYI055
+63 |     ] = union.__args__
+64 |     ...
+   |
+   = help: Combine multiple `type` members
+
+ℹ Safe fix
+59 59 | 
+60 60 | def convert_union(union: UnionType) -> _T | None:
+61 61 |     converters: tuple[
+62    |-        Union[type[_T] | type[Converter[_T]] | str] | Converter[_T] | Callable[[str], _T], ...  # PYI055
+   62 |+        Union[type[_T | Converter[_T]] | str] | Converter[_T] | Callable[[str], _T], ...  # PYI055
+63 63 |     ] = union.__args__
+64 64 |     ...
 
 

crates/ruff_linter/src/rules/flake8_pyi/snapshots/ruff_linter__rules__flake8_pyi__tests__PYI055_PYI055.pyi.snap

@@ -120,7 +120,7 @@ PYI055.pyi:10:15: PYI055 [*] Multiple `type` members in a union. Combine them in
 8  8  | z: Union[type[float, int], type[complex]]
 9  9  | 
 10    |-def func(arg: type[int] | str | type[float]) -> None: ...
-   10 |+def func(arg: type[int | float]) -> None: ...
+   10 |+def func(arg: type[int | float] | str) -> None: ...
 11 11 | 
 12 12 | # OK
 13 13 | x: type[int, str, float]