Auto merge of #26071 - petrochenkov:assert1, r=alexcrichton

`assert_eq!` has better diagnostics than `assert!` and is more helpful when something actually breaks, but the diagnostics has it's price - `assert_eq!` generate some formatting code which is slower to compile and possibly run.
[My measurements](https://internals.rust-lang.org/t/assert-a-b-or-assert-eq-a-b/1367/12?u=petrochenkov) show that presence of this formatting code doesn't affect compilation + execution time of the test suite significantly, so `assert_eq!` can be used instead of `assert!` consistently.

(Some tests doesn't reside in src/test, they are not affected by these changes, I'll probably open a separate PR for them later)

Author: bors

src/test/auxiliary/extern_calling_convention.rs

@@ -14,10 +14,10 @@
 #[inline(never)]
 #[cfg(target_arch = "x86_64")]
 pub extern "win64" fn foo(a: isize, b: isize, c: isize, d: isize) {
-    assert!(a == 1);
-    assert!(b == 2);
-    assert!(c == 3);
-    assert!(d == 4);
+    assert_eq!(a, 1);
+    assert_eq!(b, 2);
+    assert_eq!(c, 3);
+    assert_eq!(d, 4);
 
     println!("a: {}, b: {}, c: {}, d: {}",
              a, b, c, d)
@@ -26,10 +26,10 @@ pub extern "win64" fn foo(a: isize, b: isize, c: isize, d: isize) {
 #[inline(never)]
 #[cfg(any(target_arch = "x86", target_arch = "arm", target_arch = "aarch64"))]
 pub extern fn foo(a: isize, b: isize, c: isize, d: isize) {
-    assert!(a == 1);
-    assert!(b == 2);
-    assert!(c == 3);
-    assert!(d == 4);
+    assert_eq!(a, 1);
+    assert_eq!(b, 2);
+    assert_eq!(c, 3);
+    assert_eq!(d, 4);
 
     println!("a: {}, b: {}, c: {}, d: {}",
              a, b, c, d)

src/test/bench/shootout-mandelbrot.rs

@@ -54,7 +54,7 @@ const LIMIT: f64 = 2.0;
 const WORKERS: usize = 16;
 
 fn mandelbrot<W: Write>(w: usize, mut out: W) -> io::Result<()> {
-    assert!(WORKERS % 2 == 0);
+    assert_eq!(WORKERS % 2, 0);
 
     // Ensure w and h are multiples of 8.
     let w = (w + 7) / 8 * 8;
@@ -76,7 +76,7 @@ fn mandelbrot<W: Write>(w: usize, mut out: W) -> io::Result<()> {
     let v_consts = f64x2(1.5, 1.0);
 
     // A lot of this code assumes this (so do other lang benchmarks)
-    assert!(w == h);
+    assert_eq!(w, h);
     let mut precalc_r = Vec::with_capacity(w);
     let mut precalc_i = Vec::with_capacity(h);
 

src/test/compile-fail/builtin-superkinds-self-type.rs

@@ -23,5 +23,5 @@ impl <T: Sync> Foo for T { }
 fn main() {
     let (tx, rx) = channel();
     1193182.foo(tx);
-    assert!(rx.recv() == 1193182);
+    assert_eq!(rx.recv(), 1193182);
 }

src/test/compile-fail/match-static-const-lc.rs

@@ -22,7 +22,7 @@ fn f() {
         //~^ ERROR constant in pattern `a` should have an upper case name such as `A`
         (x, y) => 1 + x + y,
     };
-    assert!(r == 1);
+    assert_eq!(r, 1);
 }
 
 mod m {
@@ -37,7 +37,7 @@ fn g() {
         //~^ ERROR constant in pattern `aha` should have an upper case name such as `AHA`
         (x, y)   => 1 + x + y,
     };
-    assert!(r == 1);
+    assert_eq!(r, 1);
 }
 
 mod n {
@@ -51,7 +51,7 @@ fn h() {
 //~^ ERROR constant in pattern `not_okay` should have an upper case name such as `NOT_OKAY`
         (x, y)   => 1 + x + y,
     };
-    assert!(r == 1);
+    assert_eq!(r, 1);
 }
 
 fn main () {

src/test/compile-fail/mod_file_correct_spans.rs

@@ -13,5 +13,5 @@
 mod mod_file_aux;
 
 fn main() {
-    assert!(mod_file_aux::bar() == 10); //~ ERROR unresolved name
+    assert_eq!(mod_file_aux::bar(), 10); //~ ERROR unresolved name
 }

src/test/compile-fail/private-struct-field-cross-crate.rs

@@ -14,6 +14,6 @@ use cci_class::kitties::cat;
 
 fn main() {
   let nyan : cat = cat(52, 99);
-  assert!((nyan.meows == 52));
+  assert_eq!(nyan.meows, 52);
   //~^ ERROR field `meows` of struct `cci_class::kitties::cat` is private
 }

src/test/compile-fail/private-struct-field.rs

@@ -20,5 +20,5 @@ mod cat {
 
 fn main() {
     let nyan = cat::new_cat();
-    assert!(nyan.meows == 52);    //~ ERROR field `meows` of struct `cat::Cat` is private
+    assert_eq!(nyan.meows, 52);    //~ ERROR field `meows` of struct `cat::Cat` is private
 }

src/test/compile-fail/syntax-extension-minor.rs

@@ -17,6 +17,5 @@ pub fn main() {
     assert_eq!(concat_idents!(asd, f_f, dsa), "<.<".to_string());
     //~^ ERROR: unresolved name `asdf_fdsa`
 
-    assert!(stringify!(use_mention_distinction) ==
-                "use_mention_distinction");
+    assert_eq!(stringify!(use_mention_distinction), "use_mention_distinction");
 }

src/test/parse-fail/macros-no-semicolon.rs

@@ -11,7 +11,7 @@
 // compile-flags: -Z parse-only
 
 fn main() {
-    assert!(1 == 2)
-    assert!(3 == 4) //~ ERROR expected one of `.`, `;`, `}`, or an operator, found `assert`
+    assert_eq!(1, 2)
+    assert_eq!(3, 4) //~ ERROR expected one of `.`, `;`, `}`, or an operator, found `assert_eq`
     println!("hello");
 }

src/test/pretty/do1.rs

@@ -12,4 +12,4 @@
 
 fn f<F>(f: F) where F: Fn(isize) { f(10) }
 
-fn main() { f(|i| { assert!(i == 10) }) }
+fn main() { f(|i| { assert_eq!(i , 10) }) }