Rollup merge of #141974 - Kivooeo:tf4, r=jieyouxu

`tests/ui`: A New Order [4/N]

> [!NOTE]
>
> Intermediate commits are intended to help review, but will be squashed prior to merge.

r? ``@jieyouxu``

added stderr tag for commit which means it included generated stderr

Author: matthiaskrgr

tests/ui/char.rs

@@ -0,0 +1,33 @@
+//! Check that temporaries in the for into-iterable expr are not dropped
+//! until the end of the for expr.
+
+//@ run-pass
+
+static mut FLAGS: u64 = 0;
+
+struct AddFlags {
+    bits: u64,
+}
+
+impl Drop for AddFlags {
+    fn drop(&mut self) {
+        unsafe {
+            FLAGS += self.bits;
+        }
+    }
+}
+
+fn check_flags(expected: u64) {
+    unsafe {
+        let actual = FLAGS;
+        FLAGS = 0;
+        assert_eq!(actual, expected, "flags {}, expected {}", actual, expected);
+    }
+}
+
+fn main() {
+    for _ in &[AddFlags { bits: 1 }] {
+        check_flags(0);
+    }
+    check_flags(1);
+}

tests/ui/class-cast-to-trait.rs

@@ -1,3 +1,7 @@
+//! Check that trying to cast an enum with a Drop impl to an integer is rejected.
+//!
+//! Issue: <https://github.com/rust-lang/rust/issues/35941>
+
 enum E {
     A = 0,
 }

tests/ui/class-cast-to-trait.stderr

@@ -1,5 +1,5 @@
 error: cannot cast enum `E` into integer `u32` because it implements `Drop`
-  --> $DIR/cenum_impl_drop_cast.rs:13:13
+  --> $DIR/enum-drop-cast-error.rs:17:13
    |
 LL |     let i = e as u32;
    |             ^^^^^^^^

tests/ui/class-method-missing.rs

@@ -0,0 +1,20 @@
+//! Trait objects only allow access to methods defined in the trait.
+
+trait MyTrait {
+    fn trait_method(&mut self);
+}
+
+struct ImplType;
+
+impl MyTrait for ImplType {
+    fn trait_method(&mut self) {}
+}
+
+impl ImplType {
+    fn struct_impl_method(&mut self) {}
+}
+
+fn main() {
+    let obj: Box<dyn MyTrait> = Box::new(ImplType);
+    obj.struct_impl_method(); //~ ERROR no method named `struct_impl_method` found
+}

tests/ui/class-method-missing.stderr

@@ -0,0 +1,15 @@
+error[E0599]: no method named `struct_impl_method` found for struct `Box<dyn MyTrait>` in the current scope
+  --> $DIR/trait-object-method-error.rs:19:9
+   |
+LL |     obj.struct_impl_method();
+   |         ^^^^^^^^^^^^^^^^^^
+   |
+help: there is a method `trait_method` with a similar name
+   |
+LL -     obj.struct_impl_method();
+LL +     obj.trait_method();
+   |
+
+error: aborting due to 1 previous error
+
+For more information about this error, try `rustc --explain E0599`.

tests/ui/cleanup-rvalue-for-scope.rs

@@ -0,0 +1,13 @@
+//! Trait impls must define all required methods.
+
+trait MyTrait {
+    fn trait_method(&self);
+}
+
+struct ImplType;
+
+impl MyTrait for ImplType {} //~ ERROR not all trait items implemented, missing: `trait_method`
+
+fn main() {
+    let _ = ImplType;
+}

tests/ui/drop/for-expr-temporary-drop-scope.rs

@@ -0,0 +1,12 @@
+error[E0046]: not all trait items implemented, missing: `trait_method`
+  --> $DIR/trait-impl-missing-method.rs:9:1
+   |
+LL |     fn trait_method(&self);
+   |     ----------------------- `trait_method` from trait
+...
+LL | impl MyTrait for ImplType {}
+   | ^^^^^^^^^^^^^^^^^^^^^^^^^ missing `trait_method` in implementation
+
+error: aborting due to 1 previous error
+
+For more information about this error, try `rustc --explain E0046`.