Add crate level no_std test for swap

Author: dswij

tests/ui/crate_level_checks/no_std_swap.rs

@@ -0,0 +1,23 @@
+#![no_std]
+#![feature(lang_items, start, libc)]
+
+use core::panic::PanicInfo;
+
+#[warn(clippy::all)]
+fn main() {
+    // TODO: do somethjing with swap
+    let mut a = 42;
+    let mut b = 1337;
+
+    a = b;
+    b = a;
+}
+
+#[allow(clippy::empty_loop)]
+#[panic_handler]
+fn panic(_info: &PanicInfo) -> ! {
+    loop {}
+}
+
+#[lang = "eh_personality"]
+extern "C" fn eh_personality() {}

tests/ui/crate_level_checks/no_std_swap.stderr

@@ -0,0 +1,12 @@
+error: this looks like you are trying to swap `a` and `b`
+  --> $DIR/no_std_swap.rs:12:5
+   |
+LL | /     a = b;
+LL | |     b = a;
+   | |_________^ help: try: `core::mem::swap(&mut a, &mut b)`
+   |
+   = note: `-D clippy::almost-swapped` implied by `-D warnings`
+   = note: or maybe you should use `core::mem::replace`?
+
+error: aborting due to previous error
+

tests/ui/swap.fixed

@@ -9,7 +9,6 @@
     dead_code,
     unused_assignments
 )]
-#![feature(no_core)]
 
 struct Foo(u32);
 
@@ -107,28 +106,6 @@ fn distinct_slice() {
     std::mem::swap(&mut foo[0][1], &mut bar[1][0]);
 }
 
-fn test_no_std() {
-    #![allow(unused_attributes)]
-    #![no_std]
-
-    let mut a = 42;
-    let mut b = 1337;
-
-    core::mem::swap(&mut a, &mut b);
-}
-
-fn test_no_std_and_core() {
-    #![allow(unused_attributes)]
-    #![no_std]
-    #![no_core]
-
-    let mut a = 42;
-    let mut b = 1337;
-
-    a = b;
-    b = a;
-}
-
 #[rustfmt::skip]
 fn main() {
 

tests/ui/swap.rs

@@ -9,7 +9,6 @@
     dead_code,
     unused_assignments
 )]
-#![feature(no_core)]
 
 struct Foo(u32);
 
@@ -123,29 +122,6 @@ fn distinct_slice() {
     bar[1][0] = temp;
 }
 
-fn test_no_std() {
-    #![allow(unused_attributes)]
-    #![no_std]
-
-    let mut a = 42;
-    let mut b = 1337;
-
-    a = b;
-    b = a;
-}
-
-fn test_no_std_and_core() {
-    #![allow(unused_attributes)]
-    #![no_std]
-    #![no_core]
-
-    let mut a = 42;
-    let mut b = 1337;
-
-    a = b;
-    b = a;
-}
-
 #[rustfmt::skip]
 fn main() {
 

tests/ui/swap.stderr

@@ -1,5 +1,5 @@
 error: this looks like you are swapping `bar.a` and `bar.b` manually
-  --> $DIR/swap.rs:25:5
+  --> $DIR/swap.rs:24:5
    |
 LL | /     let temp = bar.a;
 LL | |     bar.a = bar.b;
@@ -10,55 +10,55 @@ LL | |     bar.b = temp;
    = note: or maybe you should use `std::mem::replace`?
 
 error: this looks like you are swapping elements of `foo` manually
-  --> $DIR/swap.rs:37:5
+  --> $DIR/swap.rs:36:5
    |
 LL | /     let temp = foo[0];
 LL | |     foo[0] = foo[1];
 LL | |     foo[1] = temp;
    | |_________________^ help: try: `foo.swap(0, 1)`
 
 error: this looks like you are swapping elements of `foo` manually
-  --> $DIR/swap.rs:46:5
+  --> $DIR/swap.rs:45:5
    |
 LL | /     let temp = foo[0];
 LL | |     foo[0] = foo[1];
 LL | |     foo[1] = temp;
    | |_________________^ help: try: `foo.swap(0, 1)`
 
 error: this looks like you are swapping elements of `foo` manually
-  --> $DIR/swap.rs:65:5
+  --> $DIR/swap.rs:64:5
    |
 LL | /     let temp = foo[0];
 LL | |     foo[0] = foo[1];
 LL | |     foo[1] = temp;
    | |_________________^ help: try: `foo.swap(0, 1)`
 
 error: this looks like you are swapping `a` and `b` manually
-  --> $DIR/swap.rs:76:5
+  --> $DIR/swap.rs:75:5
    |
 LL | /     a ^= b;
 LL | |     b ^= a;
 LL | |     a ^= b;
    | |___________^ help: try: `std::mem::swap(&mut a, &mut b)`
 
 error: this looks like you are swapping `bar.a` and `bar.b` manually
-  --> $DIR/swap.rs:84:5
+  --> $DIR/swap.rs:83:5
    |
 LL | /     bar.a ^= bar.b;
 LL | |     bar.b ^= bar.a;
 LL | |     bar.a ^= bar.b;
    | |___________________^ help: try: `std::mem::swap(&mut bar.a, &mut bar.b)`
 
 error: this looks like you are swapping elements of `foo` manually
-  --> $DIR/swap.rs:92:5
+  --> $DIR/swap.rs:91:5
    |
 LL | /     foo[0] ^= foo[1];
 LL | |     foo[1] ^= foo[0];
 LL | |     foo[0] ^= foo[1];
    | |_____________________^ help: try: `foo.swap(0, 1)`
 
 error: this looks like you are swapping `foo[0][1]` and `bar[1][0]` manually
-  --> $DIR/swap.rs:121:5
+  --> $DIR/swap.rs:120:5
    |
 LL | /     let temp = foo[0][1];
 LL | |     foo[0][1] = bar[1][0];
@@ -67,18 +67,8 @@ LL | |     bar[1][0] = temp;
    |
    = note: or maybe you should use `std::mem::replace`?
 
-error: this looks like you are trying to swap `a` and `b`
-  --> $DIR/swap.rs:133:5
-   |
-LL | /     a = b;
-LL | |     b = a;
-   | |_________^ help: try: `core::mem::swap(&mut a, &mut b)`
-   |
-   = note: `-D clippy::almost-swapped` implied by `-D warnings`
-   = note: or maybe you should use `core::mem::replace`?
-
 error: this looks like you are swapping `a` and `b` manually
-  --> $DIR/swap.rs:158:7
+  --> $DIR/swap.rs:134:7
    |
 LL |       ; let t = a;
    |  _______^
@@ -89,7 +79,7 @@ LL | |     b = t;
    = note: or maybe you should use `std::mem::replace`?
 
 error: this looks like you are swapping `c.0` and `a` manually
-  --> $DIR/swap.rs:167:7
+  --> $DIR/swap.rs:143:7
    |
 LL |       ; let t = c.0;
    |  _______^
@@ -100,22 +90,23 @@ LL | |     a = t;
    = note: or maybe you should use `std::mem::replace`?
 
 error: this looks like you are trying to swap `a` and `b`
-  --> $DIR/swap.rs:155:5
+  --> $DIR/swap.rs:131:5
    |
 LL | /     a = b;
 LL | |     b = a;
    | |_________^ help: try: `std::mem::swap(&mut a, &mut b)`
    |
+   = note: `-D clippy::almost-swapped` implied by `-D warnings`
    = note: or maybe you should use `std::mem::replace`?
 
 error: this looks like you are trying to swap `c.0` and `a`
-  --> $DIR/swap.rs:164:5
+  --> $DIR/swap.rs:140:5
    |
 LL | /     c.0 = a;
 LL | |     a = c.0;
    | |___________^ help: try: `std::mem::swap(&mut c.0, &mut a)`
    |
    = note: or maybe you should use `std::mem::replace`?
 
-error: aborting due to 13 previous errors
+error: aborting due to 12 previous errors