From 1fb5e0149fb85af0e49fa40329cbc352b4cba861 Mon Sep 17 00:00:00 2001
From: Kivooeo <Kivooeo123@gmail.com>
Date: Tue, 1 Jul 2025 23:33:59 +0500
Subject: [PATCH 01/23] moved tests

---
 .../weak-uninhabited-type.rs}                                     | 0
 .../underscore-prefixed-function-argument.rs}                     | 0
 .../ownership-struct-update-moved-error.rs}                       | 0
 .../ownership-struct-update-moved-error.stderr}                   | 0
 .../no-capture-closure-call.rs}                                   | 0
 .../ui/{unknown-llvm-arg.rs => codegen/llvm-args-invalid-flag.rs} | 0
 .../llvm-args-invalid-flag.stderr}                                | 0
 .../box-drop-unused-value-statement-regression.rs}                | 0
 tests/ui/{weird-exprs.rs => expr/syntax-edge-cases-lint-clean.rs} | 0
 .../hashset-enum-variant.rs}                                      | 0
 tests/ui/{write-fmt-errors.rs => io-checks/write-macro-error.rs}  | 0
 .../lang-item-unknown-definition-error.rs}                        | 0
 .../lang-item-unknown-definition-error.stderr}                    | 0
 .../module-qualified-paths-basic.rs}                              | 0
 .../{use-nested-groups.rs => modules/module-use-nested-groups.rs} | 0
 .../primitive-type-module-deprecated-paths.rs}                    | 0
 .../use-keyword-reexport-type-alias.rs}                           | 0
 .../unary-negation-unsigned-integer-error.rs}                     | 0
 .../unary-negation-unsigned-integer-error.stderr}                 | 0
 .../unwind-force-no-unwind-tables.rs}                             | 0
 .../process-spawn-failure.rs}                                     | 0
 .../windows-exit-code-still-active.rs}                            | 0
 .../diverging-expressions-unreachable-code.rs}                    | 0
 .../unreachable-code-diverging-expressions.rs}                    | 0
 .../virtual-call-parameter-handling.rs}                           | 0
 tests/ui/{unit.rs => type/unit-type-basic-usages.rs}              | 0
 .../usize-no-generic-arguments.rs}                                | 0
 .../usize-no-generic-arguments.stderr}                            | 0
 .../maybe-uninit-zero-sized-types.rs}                             | 0
 29 files changed, 0 insertions(+), 0 deletions(-)
 rename tests/ui/{weak-new-uninhabited-issue-48493.rs => allocator/weak-uninhabited-type.rs} (100%)
 rename tests/ui/{unnamed_argument_mode.rs => binding/underscore-prefixed-function-argument.rs} (100%)
 rename tests/ui/{walk-struct-literal-with.rs => borrowck/ownership-struct-update-moved-error.rs} (100%)
 rename tests/ui/{walk-struct-literal-with.stderr => borrowck/ownership-struct-update-moved-error.stderr} (100%)
 rename tests/ui/{unused-move-capture.rs => closures/no-capture-closure-call.rs} (100%)
 rename tests/ui/{unknown-llvm-arg.rs => codegen/llvm-args-invalid-flag.rs} (100%)
 rename tests/ui/{unknown-llvm-arg.stderr => codegen/llvm-args-invalid-flag.stderr} (100%)
 rename tests/ui/{unused-move.rs => drop/box-drop-unused-value-statement-regression.rs} (100%)
 rename tests/ui/{weird-exprs.rs => expr/syntax-edge-cases-lint-clean.rs} (100%)
 rename tests/ui/{wrong-hashset-issue-42918.rs => hashmap/hashset-enum-variant.rs} (100%)
 rename tests/ui/{write-fmt-errors.rs => io-checks/write-macro-error.rs} (100%)
 rename tests/ui/{unknown-language-item.rs => lang-items/lang-item-unknown-definition-error.rs} (100%)
 rename tests/ui/{unknown-language-item.stderr => lang-items/lang-item-unknown-definition-error.stderr} (100%)
 rename tests/ui/{use-import-export.rs => modules/module-qualified-paths-basic.rs} (100%)
 rename tests/ui/{use-nested-groups.rs => modules/module-use-nested-groups.rs} (100%)
 rename tests/ui/{use-module-level-int-consts.rs => modules/primitive-type-module-deprecated-paths.rs} (100%)
 rename tests/ui/{use-keyword-2.rs => modules/use-keyword-reexport-type-alias.rs} (100%)
 rename tests/ui/{unsigned-literal-negation.rs => numbers-arithmetic/unary-negation-unsigned-integer-error.rs} (100%)
 rename tests/ui/{unsigned-literal-negation.stderr => numbers-arithmetic/unary-negation-unsigned-integer-error.stderr} (100%)
 rename tests/ui/{unwind-no-uwtable.rs => panics/unwind-force-no-unwind-tables.rs} (100%)
 rename tests/ui/{wait-forked-but-failed-child.rs => process/process-spawn-failure.rs} (100%)
 rename tests/ui/{weird-exit-code.rs => process/windows-exit-code-still-active.rs} (100%)
 rename tests/ui/{unreachable-code-1.rs => reachable/diverging-expressions-unreachable-code.rs} (100%)
 rename tests/ui/{unreachable-code.rs => reachable/unreachable-code-diverging-expressions.rs} (100%)
 rename tests/ui/{virtual-call-attrs-issue-137646.rs => traits/virtual-call-parameter-handling.rs} (100%)
 rename tests/ui/{unit.rs => type/unit-type-basic-usages.rs} (100%)
 rename tests/ui/{usize-generic-argument-parent.rs => type/usize-no-generic-arguments.rs} (100%)
 rename tests/ui/{usize-generic-argument-parent.stderr => type/usize-no-generic-arguments.stderr} (100%)
 rename tests/ui/{uninit-empty-types.rs => unsafe/maybe-uninit-zero-sized-types.rs} (100%)

diff --git a/tests/ui/weak-new-uninhabited-issue-48493.rs b/tests/ui/allocator/weak-uninhabited-type.rs
similarity index 100%
rename from tests/ui/weak-new-uninhabited-issue-48493.rs
rename to tests/ui/allocator/weak-uninhabited-type.rs
diff --git a/tests/ui/unnamed_argument_mode.rs b/tests/ui/binding/underscore-prefixed-function-argument.rs
similarity index 100%
rename from tests/ui/unnamed_argument_mode.rs
rename to tests/ui/binding/underscore-prefixed-function-argument.rs
diff --git a/tests/ui/walk-struct-literal-with.rs b/tests/ui/borrowck/ownership-struct-update-moved-error.rs
similarity index 100%
rename from tests/ui/walk-struct-literal-with.rs
rename to tests/ui/borrowck/ownership-struct-update-moved-error.rs
diff --git a/tests/ui/walk-struct-literal-with.stderr b/tests/ui/borrowck/ownership-struct-update-moved-error.stderr
similarity index 100%
rename from tests/ui/walk-struct-literal-with.stderr
rename to tests/ui/borrowck/ownership-struct-update-moved-error.stderr
diff --git a/tests/ui/unused-move-capture.rs b/tests/ui/closures/no-capture-closure-call.rs
similarity index 100%
rename from tests/ui/unused-move-capture.rs
rename to tests/ui/closures/no-capture-closure-call.rs
diff --git a/tests/ui/unknown-llvm-arg.rs b/tests/ui/codegen/llvm-args-invalid-flag.rs
similarity index 100%
rename from tests/ui/unknown-llvm-arg.rs
rename to tests/ui/codegen/llvm-args-invalid-flag.rs
diff --git a/tests/ui/unknown-llvm-arg.stderr b/tests/ui/codegen/llvm-args-invalid-flag.stderr
similarity index 100%
rename from tests/ui/unknown-llvm-arg.stderr
rename to tests/ui/codegen/llvm-args-invalid-flag.stderr
diff --git a/tests/ui/unused-move.rs b/tests/ui/drop/box-drop-unused-value-statement-regression.rs
similarity index 100%
rename from tests/ui/unused-move.rs
rename to tests/ui/drop/box-drop-unused-value-statement-regression.rs
diff --git a/tests/ui/weird-exprs.rs b/tests/ui/expr/syntax-edge-cases-lint-clean.rs
similarity index 100%
rename from tests/ui/weird-exprs.rs
rename to tests/ui/expr/syntax-edge-cases-lint-clean.rs
diff --git a/tests/ui/wrong-hashset-issue-42918.rs b/tests/ui/hashmap/hashset-enum-variant.rs
similarity index 100%
rename from tests/ui/wrong-hashset-issue-42918.rs
rename to tests/ui/hashmap/hashset-enum-variant.rs
diff --git a/tests/ui/write-fmt-errors.rs b/tests/ui/io-checks/write-macro-error.rs
similarity index 100%
rename from tests/ui/write-fmt-errors.rs
rename to tests/ui/io-checks/write-macro-error.rs
diff --git a/tests/ui/unknown-language-item.rs b/tests/ui/lang-items/lang-item-unknown-definition-error.rs
similarity index 100%
rename from tests/ui/unknown-language-item.rs
rename to tests/ui/lang-items/lang-item-unknown-definition-error.rs
diff --git a/tests/ui/unknown-language-item.stderr b/tests/ui/lang-items/lang-item-unknown-definition-error.stderr
similarity index 100%
rename from tests/ui/unknown-language-item.stderr
rename to tests/ui/lang-items/lang-item-unknown-definition-error.stderr
diff --git a/tests/ui/use-import-export.rs b/tests/ui/modules/module-qualified-paths-basic.rs
similarity index 100%
rename from tests/ui/use-import-export.rs
rename to tests/ui/modules/module-qualified-paths-basic.rs
diff --git a/tests/ui/use-nested-groups.rs b/tests/ui/modules/module-use-nested-groups.rs
similarity index 100%
rename from tests/ui/use-nested-groups.rs
rename to tests/ui/modules/module-use-nested-groups.rs
diff --git a/tests/ui/use-module-level-int-consts.rs b/tests/ui/modules/primitive-type-module-deprecated-paths.rs
similarity index 100%
rename from tests/ui/use-module-level-int-consts.rs
rename to tests/ui/modules/primitive-type-module-deprecated-paths.rs
diff --git a/tests/ui/use-keyword-2.rs b/tests/ui/modules/use-keyword-reexport-type-alias.rs
similarity index 100%
rename from tests/ui/use-keyword-2.rs
rename to tests/ui/modules/use-keyword-reexport-type-alias.rs
diff --git a/tests/ui/unsigned-literal-negation.rs b/tests/ui/numbers-arithmetic/unary-negation-unsigned-integer-error.rs
similarity index 100%
rename from tests/ui/unsigned-literal-negation.rs
rename to tests/ui/numbers-arithmetic/unary-negation-unsigned-integer-error.rs
diff --git a/tests/ui/unsigned-literal-negation.stderr b/tests/ui/numbers-arithmetic/unary-negation-unsigned-integer-error.stderr
similarity index 100%
rename from tests/ui/unsigned-literal-negation.stderr
rename to tests/ui/numbers-arithmetic/unary-negation-unsigned-integer-error.stderr
diff --git a/tests/ui/unwind-no-uwtable.rs b/tests/ui/panics/unwind-force-no-unwind-tables.rs
similarity index 100%
rename from tests/ui/unwind-no-uwtable.rs
rename to tests/ui/panics/unwind-force-no-unwind-tables.rs
diff --git a/tests/ui/wait-forked-but-failed-child.rs b/tests/ui/process/process-spawn-failure.rs
similarity index 100%
rename from tests/ui/wait-forked-but-failed-child.rs
rename to tests/ui/process/process-spawn-failure.rs
diff --git a/tests/ui/weird-exit-code.rs b/tests/ui/process/windows-exit-code-still-active.rs
similarity index 100%
rename from tests/ui/weird-exit-code.rs
rename to tests/ui/process/windows-exit-code-still-active.rs
diff --git a/tests/ui/unreachable-code-1.rs b/tests/ui/reachable/diverging-expressions-unreachable-code.rs
similarity index 100%
rename from tests/ui/unreachable-code-1.rs
rename to tests/ui/reachable/diverging-expressions-unreachable-code.rs
diff --git a/tests/ui/unreachable-code.rs b/tests/ui/reachable/unreachable-code-diverging-expressions.rs
similarity index 100%
rename from tests/ui/unreachable-code.rs
rename to tests/ui/reachable/unreachable-code-diverging-expressions.rs
diff --git a/tests/ui/virtual-call-attrs-issue-137646.rs b/tests/ui/traits/virtual-call-parameter-handling.rs
similarity index 100%
rename from tests/ui/virtual-call-attrs-issue-137646.rs
rename to tests/ui/traits/virtual-call-parameter-handling.rs
diff --git a/tests/ui/unit.rs b/tests/ui/type/unit-type-basic-usages.rs
similarity index 100%
rename from tests/ui/unit.rs
rename to tests/ui/type/unit-type-basic-usages.rs
diff --git a/tests/ui/usize-generic-argument-parent.rs b/tests/ui/type/usize-no-generic-arguments.rs
similarity index 100%
rename from tests/ui/usize-generic-argument-parent.rs
rename to tests/ui/type/usize-no-generic-arguments.rs
diff --git a/tests/ui/usize-generic-argument-parent.stderr b/tests/ui/type/usize-no-generic-arguments.stderr
similarity index 100%
rename from tests/ui/usize-generic-argument-parent.stderr
rename to tests/ui/type/usize-no-generic-arguments.stderr
diff --git a/tests/ui/uninit-empty-types.rs b/tests/ui/unsafe/maybe-uninit-zero-sized-types.rs
similarity index 100%
rename from tests/ui/uninit-empty-types.rs
rename to tests/ui/unsafe/maybe-uninit-zero-sized-types.rs

From c9f97d333567b971331d4382422c5619fc587985 Mon Sep 17 00:00:00 2001
From: Kivooeo <Kivooeo123@gmail.com>
Date: Tue, 1 Jul 2025 23:37:49 +0500
Subject: [PATCH 02/23] uninit-empty-types

---
 tests/ui/unsafe/maybe-uninit-zero-sized-types.rs | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/tests/ui/unsafe/maybe-uninit-zero-sized-types.rs b/tests/ui/unsafe/maybe-uninit-zero-sized-types.rs
index 82474d873b788..e587ca554fe4d 100644
--- a/tests/ui/unsafe/maybe-uninit-zero-sized-types.rs
+++ b/tests/ui/unsafe/maybe-uninit-zero-sized-types.rs
@@ -1,6 +1,9 @@
-//@ build-pass
-// Test the uninit() construct returning various empty types.
+//! This test checks that ZSTs can be safely initialized from
+//! `MaybeUninit::uninit().assume_init()` and `std::mem::uninitialized()`
+//! (which is deprecated). This is safe because ZSTs inherently
+//! require no actual memory initialization, as they occupy no memory.
 
+//@ build-pass
 
 use std::mem::MaybeUninit;
 

From 34cea131cf4bb0f9a60baedf75b80306ad7ab341 Mon Sep 17 00:00:00 2001
From: Kivooeo <Kivooeo123@gmail.com>
Date: Tue, 1 Jul 2025 23:39:55 +0500
Subject: [PATCH 03/23] unit

---
 tests/ui/type/unit-type-basic-usages.rs | 18 ++++++++----------
 1 file changed, 8 insertions(+), 10 deletions(-)

diff --git a/tests/ui/type/unit-type-basic-usages.rs b/tests/ui/type/unit-type-basic-usages.rs
index 04404fc3f5e66..24c685aebdc0b 100644
--- a/tests/ui/type/unit-type-basic-usages.rs
+++ b/tests/ui/type/unit-type-basic-usages.rs
@@ -1,16 +1,14 @@
-//@ run-pass
-
-#![allow(unused_assignments)]
-#![allow(unknown_lints)]
+// Checks the basic usage of unit type
 
-#![allow(unused_variables)]
-#![allow(dead_assignment)]
+//@ run-pass
 
-fn f(u: ()) { return u; }
+fn f(u: ()) {
+    u
+}
 
 pub fn main() {
     let u1: () = ();
-    let mut u2: () = f(u1);
-    u2 = ();
-    return ();
+    let mut _u2: () = f(u1);
+    _u2 = ();
+    ()
 }

From 6d8cc7356b68daaa03f6db34bf6afc629d0294d6 Mon Sep 17 00:00:00 2001
From: Kivooeo <Kivooeo123@gmail.com>
Date: Tue, 1 Jul 2025 23:41:33 +0500
Subject: [PATCH 04/23] unknown-language-item

---
 tests/ui/lang-items/lang-item-unknown-definition-error.rs     | 4 +++-
 tests/ui/lang-items/lang-item-unknown-definition-error.stderr | 2 +-
 2 files changed, 4 insertions(+), 2 deletions(-)

diff --git a/tests/ui/lang-items/lang-item-unknown-definition-error.rs b/tests/ui/lang-items/lang-item-unknown-definition-error.rs
index ce206d20358a1..22812128c2d36 100644
--- a/tests/ui/lang-items/lang-item-unknown-definition-error.rs
+++ b/tests/ui/lang-items/lang-item-unknown-definition-error.rs
@@ -1,9 +1,11 @@
+//! Checks that compiler prevernt attempting to define an unrecognized or unknown lang item
+
 #![allow(unused)]
 #![feature(lang_items)]
 
 #[lang = "foo"]
 fn bar() -> ! {
-//~^^ ERROR definition of an unknown lang item: `foo`
+    //~^^ ERROR definition of an unknown lang item: `foo`
     loop {}
 }
 
diff --git a/tests/ui/lang-items/lang-item-unknown-definition-error.stderr b/tests/ui/lang-items/lang-item-unknown-definition-error.stderr
index 832f134241844..3b939757ac2b0 100644
--- a/tests/ui/lang-items/lang-item-unknown-definition-error.stderr
+++ b/tests/ui/lang-items/lang-item-unknown-definition-error.stderr
@@ -1,5 +1,5 @@
 error[E0522]: definition of an unknown lang item: `foo`
-  --> $DIR/unknown-language-item.rs:4:1
+  --> $DIR/lang-item-unknown-definition-error.rs:6:1
    |
 LL | #[lang = "foo"]
    | ^^^^^^^^^^^^^^^ definition of unknown lang item `foo`

From 41efd61a69370b29f6d647b8def3f8ded6073189 Mon Sep 17 00:00:00 2001
From: Kivooeo <Kivooeo123@gmail.com>
Date: Tue, 1 Jul 2025 23:44:18 +0500
Subject: [PATCH 05/23] unnamed_argument_mode

---
 .../binding/underscore-prefixed-function-argument.rs | 12 +++++++-----
 1 file changed, 7 insertions(+), 5 deletions(-)

diff --git a/tests/ui/binding/underscore-prefixed-function-argument.rs b/tests/ui/binding/underscore-prefixed-function-argument.rs
index 2014e0d23d849..aec2e1b9eb861 100644
--- a/tests/ui/binding/underscore-prefixed-function-argument.rs
+++ b/tests/ui/binding/underscore-prefixed-function-argument.rs
@@ -1,11 +1,13 @@
-//@ run-pass
+//! Test that functions with unnamed arguments are correct handled by compiler
 
-fn good(_a: &isize) {
-}
+//@ run-pass
 
-// unnamed argument &isize is now parse x: &isize
+fn good(_a: &isize) {}
 
-fn called<F>(_f: F) where F: FnOnce(&isize) {
+fn called<F>(_f: F)
+where
+    F: FnOnce(&isize),
+{
 }
 
 pub fn main() {

From ccbb2a4544e7a2355d02d946925c0e17ce1152d2 Mon Sep 17 00:00:00 2001
From: Kivooeo <Kivooeo123@gmail.com>
Date: Tue, 1 Jul 2025 23:49:56 +0500
Subject: [PATCH 06/23] unreachable-code-1

---
 .../diverging-expressions-unreachable-code.rs | 20 +++++++++----------
 1 file changed, 10 insertions(+), 10 deletions(-)

diff --git a/tests/ui/reachable/diverging-expressions-unreachable-code.rs b/tests/ui/reachable/diverging-expressions-unreachable-code.rs
index 9c5f7c8f45190..bb56987775ff2 100644
--- a/tests/ui/reachable/diverging-expressions-unreachable-code.rs
+++ b/tests/ui/reachable/diverging-expressions-unreachable-code.rs
@@ -3,17 +3,17 @@
 #![allow(unused_must_use)]
 #![allow(unreachable_code)]
 
-#![allow(unused_variables)]
-#![allow(dead_code)]
-
-fn id(x: bool) -> bool { x }
-
-fn call_id() {
-    let c = panic!();
-    id(c);
+fn _id(x: bool) -> bool {
+    x
 }
 
-fn call_id_3() { id(return) && id(return); }
+fn _call_id() {
+    let _c = panic!();
+    _id(_c);
+}
 
-pub fn main() {
+fn _call_id_3() {
+    _id(return) && _id(return);
 }
+
+pub fn main() {}

From f19500ec2ec31737e4d5b6e0691002dbc7fcf62e Mon Sep 17 00:00:00 2001
From: Kivooeo <Kivooeo123@gmail.com>
Date: Tue, 1 Jul 2025 23:50:46 +0500
Subject: [PATCH 07/23] unreachable-code

---
 .../unreachable-code-diverging-expressions.rs          | 10 +++++++---
 1 file changed, 7 insertions(+), 3 deletions(-)

diff --git a/tests/ui/reachable/unreachable-code-diverging-expressions.rs b/tests/ui/reachable/unreachable-code-diverging-expressions.rs
index 0c46a38d73f35..00676418002c9 100644
--- a/tests/ui/reachable/unreachable-code-diverging-expressions.rs
+++ b/tests/ui/reachable/unreachable-code-diverging-expressions.rs
@@ -26,9 +26,13 @@ fn call_id_3() {
 
 fn ret_guard() {
     match 2 {
-      x if (return) => { x; }
-      x if let true = return => { x; }
-      _ => {}
+        x if (return) => {
+            x;
+        }
+        x if let true = return => {
+            x;
+        }
+        _ => {}
     }
 }
 

From ace1230d52c1f9406aeb8eeb143bb5fea2c1b96c Mon Sep 17 00:00:00 2001
From: Kivooeo <Kivooeo123@gmail.com>
Date: Tue, 1 Jul 2025 23:51:49 +0500
Subject: [PATCH 08/23] unsigned-literal-negation

---
 .../unary-negation-unsigned-integer-error.rs                | 2 ++
 .../unary-negation-unsigned-integer-error.stderr            | 6 +++---
 2 files changed, 5 insertions(+), 3 deletions(-)

diff --git a/tests/ui/numbers-arithmetic/unary-negation-unsigned-integer-error.rs b/tests/ui/numbers-arithmetic/unary-negation-unsigned-integer-error.rs
index 943c7f79742ab..4325c8b111bc5 100644
--- a/tests/ui/numbers-arithmetic/unary-negation-unsigned-integer-error.rs
+++ b/tests/ui/numbers-arithmetic/unary-negation-unsigned-integer-error.rs
@@ -1,3 +1,5 @@
+//! This test ensures that the unary negation operator (`-`) cannot be applied to unsigned ints
+
 fn main() {
     let x = -1 as usize; //~ ERROR: cannot apply unary operator `-`
     let x = (-1) as usize; //~ ERROR: cannot apply unary operator `-`
diff --git a/tests/ui/numbers-arithmetic/unary-negation-unsigned-integer-error.stderr b/tests/ui/numbers-arithmetic/unary-negation-unsigned-integer-error.stderr
index 0bedbc1accd3b..4ce870ded9f76 100644
--- a/tests/ui/numbers-arithmetic/unary-negation-unsigned-integer-error.stderr
+++ b/tests/ui/numbers-arithmetic/unary-negation-unsigned-integer-error.stderr
@@ -1,5 +1,5 @@
 error[E0600]: cannot apply unary operator `-` to type `usize`
-  --> $DIR/unsigned-literal-negation.rs:2:13
+  --> $DIR/unary-negation-unsigned-integer-error.rs:4:13
    |
 LL |     let x = -1 as usize;
    |             ^^ cannot apply unary operator `-`
@@ -12,7 +12,7 @@ LL +     let x = usize::MAX;
    |
 
 error[E0600]: cannot apply unary operator `-` to type `usize`
-  --> $DIR/unsigned-literal-negation.rs:3:13
+  --> $DIR/unary-negation-unsigned-integer-error.rs:5:13
    |
 LL |     let x = (-1) as usize;
    |             ^^^^ cannot apply unary operator `-`
@@ -25,7 +25,7 @@ LL +     let x = usize::MAX;
    |
 
 error[E0600]: cannot apply unary operator `-` to type `u32`
-  --> $DIR/unsigned-literal-negation.rs:4:18
+  --> $DIR/unary-negation-unsigned-integer-error.rs:6:18
    |
 LL |     let x: u32 = -1;
    |                  ^^ cannot apply unary operator `-`

From b2eb2b162f3fceab142101f0e8835c330fcd4731 Mon Sep 17 00:00:00 2001
From: Kivooeo <Kivooeo123@gmail.com>
Date: Tue, 1 Jul 2025 23:54:50 +0500
Subject: [PATCH 09/23] unused-move-capture

---
 tests/ui/closures/no-capture-closure-call.rs | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/tests/ui/closures/no-capture-closure-call.rs b/tests/ui/closures/no-capture-closure-call.rs
index 5f42bcbe280e6..29e5ac635b421 100644
--- a/tests/ui/closures/no-capture-closure-call.rs
+++ b/tests/ui/closures/no-capture-closure-call.rs
@@ -1,3 +1,5 @@
+//! Sanity check for no capture closures
+
 //@ run-pass
 
 pub fn main() {

From 9203c44377060ad12c315e699a3fdfc395e5de05 Mon Sep 17 00:00:00 2001
From: Kivooeo <Kivooeo123@gmail.com>
Date: Tue, 1 Jul 2025 23:56:32 +0500
Subject: [PATCH 10/23] unused-move

---
 .../box-drop-unused-value-statement-regression.rs  | 14 +++++++-------
 1 file changed, 7 insertions(+), 7 deletions(-)

diff --git a/tests/ui/drop/box-drop-unused-value-statement-regression.rs b/tests/ui/drop/box-drop-unused-value-statement-regression.rs
index 3d5eff2c48d50..43865e0844457 100644
--- a/tests/ui/drop/box-drop-unused-value-statement-regression.rs
+++ b/tests/ui/drop/box-drop-unused-value-statement-regression.rs
@@ -1,12 +1,12 @@
-//@ run-pass
-// Issue #3878
-// Issue Name: Unused move causes a crash
-// Abstract: zero-fill to block after drop
-
+//! Regression test for a crash caused by an "unsused move"
+//! (specifically, a variable bound to a `Box` used as a statement)
+//! leading to incorrect memory zero-filling after drop.
+//!
+//! Regression test for <https://github.com/rust-lang/rust/issues/3878>.
 
-#![allow(path_statements)]
+//@ run-pass
 
 pub fn main() {
     let y: Box<_> = Box::new(1);
-    y;
+    drop(y);
 }

From c2a8336806dce6a67dcca09e791c1a871c3784a2 Mon Sep 17 00:00:00 2001
From: Kivooeo <Kivooeo123@gmail.com>
Date: Tue, 1 Jul 2025 23:57:28 +0500
Subject: [PATCH 11/23] unwind-no-uwtable

---
 tests/ui/panics/unwind-force-no-unwind-tables.rs | 15 +++++++++++----
 1 file changed, 11 insertions(+), 4 deletions(-)

diff --git a/tests/ui/panics/unwind-force-no-unwind-tables.rs b/tests/ui/panics/unwind-force-no-unwind-tables.rs
index fb8082e31880a..2226e4dd03ebc 100644
--- a/tests/ui/panics/unwind-force-no-unwind-tables.rs
+++ b/tests/ui/panics/unwind-force-no-unwind-tables.rs
@@ -1,3 +1,7 @@
+//! This test checks that Rust's unwinding mechanism correctly executes `Drop`
+//! implementations during stack unwinding, even when unwind tables (`uwtable`)
+//! are explicitly disabled via `-C force-unwind-tables=n`.
+
 //@ run-pass
 //@ needs-unwind
 //@ ignore-windows target requires uwtable
@@ -26,9 +30,12 @@ fn increase(count: &mut u8) {
 
 fn main() {
     let mut count = 0;
-    assert!(panic::catch_unwind(AssertUnwindSafe(
-        #[inline(never)]
-        || increase(&mut count)
-    )).is_err());
+    assert!(
+        panic::catch_unwind(AssertUnwindSafe(
+            #[inline(never)]
+            || increase(&mut count)
+        ))
+        .is_err()
+    );
     assert_eq!(count, 1);
 }

From 79e155c6c275be88acdbf774fcf99142d23a06ea Mon Sep 17 00:00:00 2001
From: Kivooeo <Kivooeo123@gmail.com>
Date: Tue, 1 Jul 2025 23:59:01 +0500
Subject: [PATCH 12/23] use-import-export

---
 tests/ui/modules/module-qualified-paths-basic.rs | 15 ++++++++++++---
 1 file changed, 12 insertions(+), 3 deletions(-)

diff --git a/tests/ui/modules/module-qualified-paths-basic.rs b/tests/ui/modules/module-qualified-paths-basic.rs
index d948ffc1520b3..c02f6060caa71 100644
--- a/tests/ui/modules/module-qualified-paths-basic.rs
+++ b/tests/ui/modules/module-qualified-paths-basic.rs
@@ -1,11 +1,20 @@
+//! Checks that functions from different modules are accessible via their fully-qualified paths.
+
 //@ run-pass
 
 mod foo {
-    pub fn x() -> isize { return 1; }
+    pub fn x() -> isize {
+        return 1;
+    }
 }
 
 mod bar {
-    pub fn y() -> isize { return 1; }
+    pub fn y() -> isize {
+        return 1;
+    }
 }
 
-pub fn main() { foo::x(); bar::y(); }
+pub fn main() {
+    foo::x();
+    bar::y();
+}

From 698c614f494f108599eff405f785c7682c317a5a Mon Sep 17 00:00:00 2001
From: Kivooeo <Kivooeo123@gmail.com>
Date: Wed, 2 Jul 2025 00:00:20 +0500
Subject: [PATCH 13/23] use-keyword-2

---
 tests/ui/modules/use-keyword-reexport-type-alias.rs | 10 ++++++----
 1 file changed, 6 insertions(+), 4 deletions(-)

diff --git a/tests/ui/modules/use-keyword-reexport-type-alias.rs b/tests/ui/modules/use-keyword-reexport-type-alias.rs
index 4f3d1ee500d80..c62bd9687ae62 100644
--- a/tests/ui/modules/use-keyword-reexport-type-alias.rs
+++ b/tests/ui/modules/use-keyword-reexport-type-alias.rs
@@ -1,18 +1,20 @@
+//! Checks module re-exports, aliasing with `pub use`,
+//! and calling private methods via `Self` in an impl block.
+
 //@ run-pass
 
 #![allow(unused_variables)]
 pub struct A;
 
 mod test {
-    pub use super :: A;
-
-    pub use self :: A as B;
+    pub use self::A as B;
+    pub use super::A;
 }
 
 impl A {
     fn f() {}
     fn g() {
-        Self :: f()
+        Self::f()
     }
 }
 

From cc1df9f85d6c3249cec8c3dfb6715a2e975724f7 Mon Sep 17 00:00:00 2001
From: Kivooeo <Kivooeo123@gmail.com>
Date: Wed, 2 Jul 2025 00:02:54 +0500
Subject: [PATCH 14/23] use-module-level-int-consts

---
 tests/ui/modules/primitive-type-module-deprecated-paths.rs | 7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/tests/ui/modules/primitive-type-module-deprecated-paths.rs b/tests/ui/modules/primitive-type-module-deprecated-paths.rs
index 6e8c7053c5760..5c9d2a616b3f0 100644
--- a/tests/ui/modules/primitive-type-module-deprecated-paths.rs
+++ b/tests/ui/modules/primitive-type-module-deprecated-paths.rs
@@ -1,9 +1,10 @@
+//! Make sure the module level constants are still there and accessible even after
+//! the corresponding associated constants have been added, and later stabilized.
+
 //@ run-pass
 
-// Make sure the module level constants are still there and accessible even after
-// the corresponding associated constants have been added, and later stabilized.
 #![allow(deprecated, deprecated_in_future)]
-use std::{u16, f32};
+use std::{f32, u16};
 
 fn main() {
     let _ = u16::MAX;

From a3922df0922432d86867c427e16bef1c1a37c0c9 Mon Sep 17 00:00:00 2001
From: Kivooeo <Kivooeo123@gmail.com>
Date: Wed, 2 Jul 2025 00:05:06 +0500
Subject: [PATCH 15/23] use-nested-groups

---
 tests/ui/modules/module-use-nested-groups.rs | 11 ++++++++---
 1 file changed, 8 insertions(+), 3 deletions(-)

diff --git a/tests/ui/modules/module-use-nested-groups.rs b/tests/ui/modules/module-use-nested-groups.rs
index c5d66a8693533..9ac3246735fc8 100644
--- a/tests/ui/modules/module-use-nested-groups.rs
+++ b/tests/ui/modules/module-use-nested-groups.rs
@@ -1,3 +1,5 @@
+//! Checks complex `use` syntax and availability of types across nested modules.
+
 //@ run-pass
 
 mod a {
@@ -15,10 +17,13 @@ mod a {
 }
 
 // Test every possible part of the syntax
-use a::{B, d::{self, *, g::H}};
-
 // Test a more common use case
-use std::sync::{Arc, atomic::{AtomicBool, Ordering}};
+use std::sync::Arc;
+use std::sync::atomic::{AtomicBool, Ordering};
+
+use a::B;
+use a::d::g::H;
+use a::d::{self, *};
 
 fn main() {
     let _: B;

From bc8af49a3636a4e434a9d8c6d24fbfdf899bb142 Mon Sep 17 00:00:00 2001
From: Kivooeo <Kivooeo123@gmail.com>
Date: Wed, 2 Jul 2025 00:08:29 +0500
Subject: [PATCH 16/23] usize-generic-argument-parent

---
 tests/ui/type/usize-no-generic-arguments.rs     | 2 ++
 tests/ui/type/usize-no-generic-arguments.stderr | 2 +-
 2 files changed, 3 insertions(+), 1 deletion(-)

diff --git a/tests/ui/type/usize-no-generic-arguments.rs b/tests/ui/type/usize-no-generic-arguments.rs
index 4ab80d944a56f..d4d1eea757cab 100644
--- a/tests/ui/type/usize-no-generic-arguments.rs
+++ b/tests/ui/type/usize-no-generic-arguments.rs
@@ -1,3 +1,5 @@
+//! Sanity test that primitives cannot have const generics.
+
 fn foo() {
     let x: usize<foo>; //~ ERROR const arguments are not allowed on builtin type `usize`
 }
diff --git a/tests/ui/type/usize-no-generic-arguments.stderr b/tests/ui/type/usize-no-generic-arguments.stderr
index 9c081a287ed75..f1f3456461fc6 100644
--- a/tests/ui/type/usize-no-generic-arguments.stderr
+++ b/tests/ui/type/usize-no-generic-arguments.stderr
@@ -1,5 +1,5 @@
 error[E0109]: const arguments are not allowed on builtin type `usize`
-  --> $DIR/usize-generic-argument-parent.rs:2:18
+  --> $DIR/usize-no-generic-arguments.rs:4:18
    |
 LL |     let x: usize<foo>;
    |            ----- ^^^ const argument not allowed

From b987f400417845b9aab2aed462420f17201fd508 Mon Sep 17 00:00:00 2001
From: Kivooeo <Kivooeo123@gmail.com>
Date: Wed, 2 Jul 2025 00:10:07 +0500
Subject: [PATCH 17/23] virtual-call-attrs-issue-137646

---
 tests/ui/traits/virtual-call-parameter-handling.rs | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/tests/ui/traits/virtual-call-parameter-handling.rs b/tests/ui/traits/virtual-call-parameter-handling.rs
index e80bd5768a429..71ed459d15aca 100644
--- a/tests/ui/traits/virtual-call-parameter-handling.rs
+++ b/tests/ui/traits/virtual-call-parameter-handling.rs
@@ -1,5 +1,7 @@
-//! Regression test for https://github.com/rust-lang/rust/issues/137646.
-//! The parameter value at all calls to `check` should be `(1, 1, 1)`.
+//! This test checks the correct parameter handling during virtual method calls
+//! through a `dyn Trait` object.
+//!
+//! Regression test for: <https://github.com/rust-lang/rust/issues/137646>
 
 //@ run-pass
 

From b1086cea938046bbacf0aa64e2a28718ec87bed8 Mon Sep 17 00:00:00 2001
From: Kivooeo <Kivooeo123@gmail.com>
Date: Wed, 2 Jul 2025 00:13:43 +0500
Subject: [PATCH 18/23] wait-forked-but-failed-child

---
 tests/ui/process/process-spawn-failure.rs | 47 +++++++++++++++--------
 1 file changed, 30 insertions(+), 17 deletions(-)

diff --git a/tests/ui/process/process-spawn-failure.rs b/tests/ui/process/process-spawn-failure.rs
index 4a7f2bee9d954..0950b044c97ca 100644
--- a/tests/ui/process/process-spawn-failure.rs
+++ b/tests/ui/process/process-spawn-failure.rs
@@ -1,3 +1,9 @@
+//! Tests that repeatedly spawning a failing command does not create zombie processes.
+//! Spawns a deliberately invalid command multiple times, verifies each spawn fails,
+//! then uses `ps` (on Unix) to detect any leftover zombie (defunct) child processes.
+//! Checks Rust's process spawning cleans up resources properly.
+//! Skipped on platforms without `ps` utility.
+
 //@ run-pass
 //@ needs-subprocess
 //@ ignore-vxworks no 'ps'
@@ -36,35 +42,42 @@ fn find_zombies() {
     // the PPID column contains a "-" for the respective process.
     // Filter out any lines that have a "-" as the PPID as the PPID is
     // expected to be an integer.
-    let filtered_ps: Vec<_> = ps_output
-        .lines()
-        .filter(|line| line.split_whitespace().nth(1) != Some("-"))
-        .collect();
+    let filtered_ps: Vec<_> =
+        ps_output.lines().filter(|line| line.split_whitespace().nth(1) != Some("-")).collect();
 
     for (line_no, line) in filtered_ps.into_iter().enumerate() {
-        if 0 < line_no && 0 < line.len() &&
-           my_pid == line.split(' ').filter(|w| 0 < w.len()).nth(1)
-                         .expect("1st column should be PPID")
-                         .parse().ok()
-                         .expect("PPID string into integer") &&
-           line.contains("defunct") {
+        if 0 < line_no
+            && 0 < line.len()
+            && my_pid
+                == line
+                    .split(' ')
+                    .filter(|w| 0 < w.len())
+                    .nth(1)
+                    .expect("1st column should be PPID")
+                    .parse()
+                    .ok()
+                    .expect("PPID string into integer")
+            && line.contains("defunct")
+        {
             panic!("Zombie child {}", line);
         }
     }
 }
 
 #[cfg(windows)]
-fn find_zombies() { }
+fn find_zombies() {}
 
 fn main() {
     let too_long = format!("/NoSuchCommand{:0300}", 0u8);
 
-    let _failures = (0..100).map(|_| {
-        let mut cmd = Command::new(&too_long);
-        let failed = cmd.spawn();
-        assert!(failed.is_err(), "Make sure the command fails to spawn(): {:?}", cmd);
-        failed
-    }).collect::<Vec<_>>();
+    let _failures = (0..100)
+        .map(|_| {
+            let mut cmd = Command::new(&too_long);
+            let failed = cmd.spawn();
+            assert!(failed.is_err(), "Make sure the command fails to spawn(): {:?}", cmd);
+            failed
+        })
+        .collect::<Vec<_>>();
 
     find_zombies();
     // then _failures goes out of scope

From a927d1171aadc20d2f2d3dcb325ae133eb6bef0f Mon Sep 17 00:00:00 2001
From: Kivooeo <Kivooeo123@gmail.com>
Date: Wed, 2 Jul 2025 00:15:33 +0500
Subject: [PATCH 19/23] walk-struct-literal-with

---
 .../ownership-struct-update-moved-error.rs       | 16 +++++++++-------
 .../ownership-struct-update-moved-error.stderr   | 12 ++++++------
 2 files changed, 15 insertions(+), 13 deletions(-)

diff --git a/tests/ui/borrowck/ownership-struct-update-moved-error.rs b/tests/ui/borrowck/ownership-struct-update-moved-error.rs
index ee1a77eb9a48a..62fc1f42969f4 100644
--- a/tests/ui/borrowck/ownership-struct-update-moved-error.rs
+++ b/tests/ui/borrowck/ownership-struct-update-moved-error.rs
@@ -1,17 +1,19 @@
-struct Mine{
+//! Checks borrow after move error when using `self` consuming method with struct update syntax.
+
+struct Mine {
     test: String,
-    other_val: isize
+    other_val: isize,
 }
 
-impl Mine{
-    fn make_string_bar(mut self) -> Mine{
+impl Mine {
+    fn make_string_bar(mut self) -> Mine {
         self.test = "Bar".to_string();
         self
     }
 }
 
-fn main(){
-    let start = Mine{test:"Foo".to_string(), other_val:0};
-    let end = Mine{other_val:1, ..start.make_string_bar()};
+fn main() {
+    let start = Mine { test: "Foo".to_string(), other_val: 0 };
+    let end = Mine { other_val: 1, ..start.make_string_bar() };
     println!("{}", start.test); //~ ERROR borrow of moved value: `start`
 }
diff --git a/tests/ui/borrowck/ownership-struct-update-moved-error.stderr b/tests/ui/borrowck/ownership-struct-update-moved-error.stderr
index 34b501f8ec881..83cfc7bb412cf 100644
--- a/tests/ui/borrowck/ownership-struct-update-moved-error.stderr
+++ b/tests/ui/borrowck/ownership-struct-update-moved-error.stderr
@@ -1,17 +1,17 @@
 error[E0382]: borrow of moved value: `start`
-  --> $DIR/walk-struct-literal-with.rs:16:20
+  --> $DIR/ownership-struct-update-moved-error.rs:18:20
    |
-LL |     let start = Mine{test:"Foo".to_string(), other_val:0};
+LL |     let start = Mine { test: "Foo".to_string(), other_val: 0 };
    |         ----- move occurs because `start` has type `Mine`, which does not implement the `Copy` trait
-LL |     let end = Mine{other_val:1, ..start.make_string_bar()};
-   |                                         ----------------- `start` moved due to this method call
+LL |     let end = Mine { other_val: 1, ..start.make_string_bar() };
+   |                                            ----------------- `start` moved due to this method call
 LL |     println!("{}", start.test);
    |                    ^^^^^^^^^^ value borrowed here after move
    |
 note: `Mine::make_string_bar` takes ownership of the receiver `self`, which moves `start`
-  --> $DIR/walk-struct-literal-with.rs:7:28
+  --> $DIR/ownership-struct-update-moved-error.rs:9:28
    |
-LL |     fn make_string_bar(mut self) -> Mine{
+LL |     fn make_string_bar(mut self) -> Mine {
    |                            ^^^^
    = note: this error originates in the macro `$crate::format_args_nl` which comes from the expansion of the macro `println` (in Nightly builds, run with -Z macro-backtrace for more info)
 

From 10951bb440fa657fba7059ca1ab2d15c04c558fb Mon Sep 17 00:00:00 2001
From: Kivooeo <Kivooeo123@gmail.com>
Date: Wed, 2 Jul 2025 00:17:45 +0500
Subject: [PATCH 20/23] weak-new-uninhabited-issue-48493

---
 tests/ui/allocator/weak-uninhabited-type.rs | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/tests/ui/allocator/weak-uninhabited-type.rs b/tests/ui/allocator/weak-uninhabited-type.rs
index ce7d5786b41bb..74258eedc6ac3 100644
--- a/tests/ui/allocator/weak-uninhabited-type.rs
+++ b/tests/ui/allocator/weak-uninhabited-type.rs
@@ -1,7 +1,13 @@
+//! Checks that `Weak` pointers can be created with an empty enum type parameter.
+//! And generic `Weak` handles zero-variant enums without error.
+//!
+//! Regression test for <https://github.com/rust-lang/rust/issues/48493>
+
 //@ run-pass
 
+enum Void {}
+
 fn main() {
-    enum Void {}
     let _ = std::rc::Weak::<Void>::new();
     let _ = std::sync::Weak::<Void>::new();
 }

From d08fb12f40d081d433ccd6d8cea5a513cadb4208 Mon Sep 17 00:00:00 2001
From: Kivooeo <Kivooeo123@gmail.com>
Date: Wed, 2 Jul 2025 00:18:17 +0500
Subject: [PATCH 21/23] weird-exit-code

---
 .../process/windows-exit-code-still-active.rs | 24 +++++++++----------
 1 file changed, 11 insertions(+), 13 deletions(-)

diff --git a/tests/ui/process/windows-exit-code-still-active.rs b/tests/ui/process/windows-exit-code-still-active.rs
index e016343f8ba2f..e661a4f6adc53 100644
--- a/tests/ui/process/windows-exit-code-still-active.rs
+++ b/tests/ui/process/windows-exit-code-still-active.rs
@@ -1,23 +1,21 @@
+//! On Windows the GetExitCodeProcess API is used to get the exit code of a
+//! process, but it's easy to mistake a process exiting with the code 259 as
+//! "still running" because this is the value of the STILL_ACTIVE constant. Make
+//! sure we handle this case in the standard library and correctly report the
+//! status.
+//!
+//! Note that this is disabled on unix as processes exiting with 259 will have
+//! their exit status truncated to 3 (only the lower 8 bits are used).
+
 //@ run-pass
-// On Windows the GetExitCodeProcess API is used to get the exit code of a
-// process, but it's easy to mistake a process exiting with the code 259 as
-// "still running" because this is the value of the STILL_ACTIVE constant. Make
-// sure we handle this case in the standard library and correctly report the
-// status.
-//
-// Note that this is disabled on unix as processes exiting with 259 will have
-// their exit status truncated to 3 (only the lower 8 bits are used).
 
 #[cfg(windows)]
 fn main() {
-    use std::process::{self, Command};
     use std::env;
+    use std::process::{self, Command};
 
     if env::args().len() == 1 {
-        let status = Command::new(env::current_exe().unwrap())
-                             .arg("foo")
-                             .status()
-                             .unwrap();
+        let status = Command::new(env::current_exe().unwrap()).arg("foo").status().unwrap();
         assert_eq!(status.code(), Some(259));
     } else {
         process::exit(259);

From 14f84f36b1ac7f88a899d2759e94966bfe32edd1 Mon Sep 17 00:00:00 2001
From: Kivooeo <Kivooeo123@gmail.com>
Date: Wed, 2 Jul 2025 00:20:30 +0500
Subject: [PATCH 22/23] write-fmt-errors

---
 tests/ui/io-checks/write-macro-error.rs | 13 ++++++++++---
 1 file changed, 10 insertions(+), 3 deletions(-)

diff --git a/tests/ui/io-checks/write-macro-error.rs b/tests/ui/io-checks/write-macro-error.rs
index b48fa3f11ccb1..857ea0024e16c 100644
--- a/tests/ui/io-checks/write-macro-error.rs
+++ b/tests/ui/io-checks/write-macro-error.rs
@@ -1,3 +1,6 @@
+//! Tests that errors from both the writer (`Write::write`) and formatter (`Display::fmt`)
+//! are correctly propagated: writer errors return `Err`, formatter errors cause panics.
+
 //@ run-pass
 //@ needs-unwind
 
@@ -24,7 +27,9 @@ impl Write for ErrorWriter {
         Err(Error::new(WRITER_ERROR, "not connected"))
     }
 
-    fn flush(&mut self) -> io::Result<()> { Ok(()) }
+    fn flush(&mut self) -> io::Result<()> {
+        Ok(())
+    }
 }
 
 fn main() {
@@ -37,7 +42,8 @@ fn main() {
     let err = res.expect_err("formatter error did not lead to panic").downcast::<&str>().unwrap();
     assert!(
         err.contains("formatting trait implementation returned an error"),
-        "unexpected panic: {}", err
+        "unexpected panic: {}",
+        err
     );
 
     // Writer error when there's some string before the first `{}`
@@ -50,6 +56,7 @@ fn main() {
     let err = res.expect_err("formatter error did not lead to panic").downcast::<&str>().unwrap();
     assert!(
         err.contains("formatting trait implementation returned an error"),
-        "unexpected panic: {}", err
+        "unexpected panic: {}",
+        err
     );
 }

From f6b57e4b5c7e9a924f0a535805510d9f3cc4b279 Mon Sep 17 00:00:00 2001
From: Kivooeo <Kivooeo123@gmail.com>
Date: Wed, 2 Jul 2025 00:23:41 +0500
Subject: [PATCH 23/23] wrong-hashset-issue-42918.rs

---
 tests/ui/hashmap/hashset-enum-variant.rs | 14 ++++++++------
 1 file changed, 8 insertions(+), 6 deletions(-)

diff --git a/tests/ui/hashmap/hashset-enum-variant.rs b/tests/ui/hashmap/hashset-enum-variant.rs
index 5795cc527cf27..ac715c7c54739 100644
--- a/tests/ui/hashmap/hashset-enum-variant.rs
+++ b/tests/ui/hashmap/hashset-enum-variant.rs
@@ -1,26 +1,28 @@
+//! Checks that `HashSet` initialization with enum variants correctly includes only
+//! specified variants, preventing platform-specific bugs
+//! where all enum variants were mistakenly included
+//!
+//! Regression test for <https://github.com/rust-lang/rust/issues/42918>
+
 //@ run-pass
-//
-#![allow(dead_code)]
 //@ compile-flags: -O
 
+#![allow(dead_code)]
+
 use std::collections::HashSet;
 
 #[derive(PartialEq, Debug, Hash, Eq, Clone, PartialOrd, Ord)]
 enum MyEnum {
     E0,
-
     E1,
-
     E2,
     E3,
     E4,
-
     E5,
     E6,
     E7,
 }
 
-
 fn main() {
     use MyEnum::*;
     let s: HashSet<_> = [E4, E1].iter().cloned().collect();