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

Diff for: 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)

Diff for: 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);
 

Diff for: 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);
 }

Diff for: 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 () {

Diff for: 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
 }

Diff for: 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
 }

Diff for: 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
 }

Diff for: 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");
 }

Diff for: 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");
 }

Diff for: 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) }) }

Diff for: src/test/run-fail/panic.rs

@@ -9,4 +9,4 @@
 // except according to those terms.
 
 // error-pattern:1 == 2
-fn main() { assert!((1 == 2)); }
+fn main() { assert!(1 == 2); }

Diff for: src/test/run-make/extern-flag-disambiguates/d.rs

@@ -16,6 +16,6 @@ extern crate c;
 fn t(a: &'static usize) -> usize { a as *const _ as usize }
 
 fn main() {
-    assert!(t(a::token()) == t(b::a_token()));
+    assert_eq!(t(a::token()), t(b::a_token()));
     assert!(t(a::token()) != t(c::a_token()));
 }

Diff for: src/test/run-make/static-unwinding/main.rs

@@ -28,7 +28,7 @@ fn main() {
     }).join().err().unwrap();
 
     unsafe {
-        assert!(lib::statik == 1);
-        assert!(statik == 1);
+        assert_eq!(lib::statik, 1);
+        assert_eq!(statik, 1);
     }
 }

Diff for: src/test/run-pass-fulldeps/compiler-calls.rs

@@ -78,5 +78,5 @@ fn main() {
     // we should never get use this filename, but lets make sure they are valid args.
     let args = vec!["compiler-calls".to_string(), "foo.rs".to_string()];
     rustc_driver::run_compiler(&args, &mut tc);
-    assert!(tc.count == 30);
+    assert_eq!(tc.count, 30);
 }

Diff for: src/test/run-pass-valgrind/dst-dtor-2.rs

@@ -27,6 +27,6 @@ pub fn main() {
         let _x: Box<Fat<[Foo]>> = Box::<Fat<[Foo; 3]>>::new(Fat { f: [Foo, Foo, Foo] });
     }
     unsafe {
-        assert!(DROP_RAN == 3);
+        assert_eq!(DROP_RAN, 3);
     }
 }

Diff for: src/test/run-pass/arith-2.rs

@@ -13,6 +13,6 @@
 
 pub fn main() {
     let i32_c: isize = 0x10101010;
-    assert!(i32_c + i32_c * 2 / 3 * 2 + (i32_c - 7 % 3) ==
+    assert_eq!(i32_c + i32_c * 2 / 3 * 2 + (i32_c - 7 % 3),
                  i32_c + i32_c * 2 / 3 * 2 + (i32_c - 7 % 3));
 }

Diff for: src/test/run-pass/artificial-block.rs

@@ -11,4 +11,4 @@
 
 fn f() -> isize { { return 3; } }
 
-pub fn main() { assert!((f() == 3)); }
+pub fn main() { assert_eq!(f(), 3); }

Diff for: src/test/run-pass/assignability-trait.rs

@@ -43,7 +43,7 @@ fn length<A, T: iterable<A>>(x: T) -> usize {
 pub fn main() {
     let x: Vec<isize> = vec!(0,1,2,3);
     // Call a method
-    x.iterate(|y| { assert!(x[*y as usize] == *y); true });
+    x.iterate(|y| { assert_eq!(x[*y as usize], *y); true });
     // Call a parameterized function
     assert_eq!(length(x.clone()), x.len());
     // Call a parameterized function, with type arguments that require

Diff for: src/test/run-pass/associated-types-return.rs

@@ -16,7 +16,7 @@ pub trait Foo {
     fn boo(&self) -> <Self as Foo>::A;
 }
 
-#[derive(PartialEq)]
+#[derive(PartialEq, Debug)]
 pub struct Bar;
 
 impl Foo for isize {
@@ -44,12 +44,12 @@ fn foo2<I: Foo>(x: I) -> <I as Foo>::A {
 
 pub fn main() {
     let a = 42;
-    assert!(foo2(a) == 42);
+    assert_eq!(foo2(a), 42);
 
     let a = Bar;
-    assert!(foo2(a) == 43);
+    assert_eq!(foo2(a), 43);
 
     let a = 'a';
     foo1(a);
-    assert!(foo2(a) == Bar);
+    assert_eq!(foo2(a), Bar);
 }

Diff for: src/test/run-pass/bool.rs

@@ -74,8 +74,8 @@ fn main() {
     assert!(true >= false);
     assert!(!(true <= false));
 
-    assert!(true.cmp(&true) == Equal);
-    assert!(false.cmp(&false) == Equal);
-    assert!(true.cmp(&false) == Greater);
-    assert!(false.cmp(&true) == Less);
+    assert_eq!(true.cmp(&true), Equal);
+    assert_eq!(false.cmp(&false), Equal);
+    assert_eq!(true.cmp(&false), Greater);
+    assert_eq!(false.cmp(&true), Less);
 }

Diff for: src/test/run-pass/builtin-superkinds-capabilities-transitive.rs

@@ -30,5 +30,5 @@ fn foo<T: Foo + 'static>(val: T, chan: Sender<T>) {
 pub fn main() {
     let (tx, rx) = channel();
     foo(31337, tx);
-    assert!(rx.recv().unwrap() == 31337);
+    assert_eq!(rx.recv().unwrap(), 31337);
 }

Diff for: src/test/run-pass/builtin-superkinds-capabilities-xc.rs

@@ -20,7 +20,7 @@ extern crate trait_superkinds_in_metadata;
 use std::sync::mpsc::{channel, Sender, Receiver};
 use trait_superkinds_in_metadata::{RequiresRequiresShareAndSend, RequiresShare};
 
-#[derive(PartialEq)]
+#[derive(PartialEq, Debug)]
 struct X<T>(T);
 
 impl <T: Sync> RequiresShare for X<T> { }
@@ -33,5 +33,5 @@ fn foo<T: RequiresRequiresShareAndSend + 'static>(val: T, chan: Sender<T>) {
 pub fn main() {
     let (tx, rx): (Sender<X<isize>>, Receiver<X<isize>>) = channel();
     foo(X(31337), tx);
-    assert!(rx.recv().unwrap() == X(31337));
+    assert_eq!(rx.recv().unwrap(), X(31337));
 }

Diff for: src/test/run-pass/builtin-superkinds-capabilities.rs

@@ -26,5 +26,5 @@ fn foo<T: Foo + 'static>(val: T, chan: Sender<T>) {
 pub fn main() {
     let (tx, rx): (Sender<isize>, Receiver<isize>) = channel();
     foo(31337, tx);
-    assert!(rx.recv().unwrap() == 31337);
+    assert_eq!(rx.recv().unwrap(), 31337);
 }

Diff for: src/test/run-pass/builtin-superkinds-self-type.rs

@@ -25,5 +25,5 @@ impl <T: Send + 'static> Foo for T { }
 pub fn main() {
     let (tx, rx) = channel();
     1193182.foo(tx);
-    assert!(rx.recv().unwrap() == 1193182);
+    assert_eq!(rx.recv().unwrap(), 1193182);
 }

Diff for: src/test/run-pass/c-stack-returning-int64.rs

@@ -37,6 +37,6 @@ fn atoll(s: String) -> i64 {
 
 pub fn main() {
     assert_eq!(atol("1024".to_string()) * 10, atol("10240".to_string()));
-    assert!((atoll("11111111111111111".to_string()) * 10) ==
+    assert_eq!((atoll("11111111111111111".to_string()) * 10),
              atoll("111111111111111110".to_string()));
 }

Diff for: src/test/run-pass/cci_impl_exe.rs

@@ -22,6 +22,6 @@ pub fn main() {
 
         //let bt1 = sys::frame_address();
         //println!("%?", bt1);
-        //assert!(bt0 == bt1);
+        //assert_eq!(bt0, bt1);
     })
 }

Diff for: src/test/run-pass/cci_iter_exe.rs

@@ -17,6 +17,6 @@ pub fn main() {
     //println!("%?", bt0);
     cci_iter_lib::iter(&[1, 2, 3], |i| {
         println!("{}", *i);
-        //assert!(bt0 == sys::rusti::frame_address(2));
+        //assert_eq!(bt0, sys::rusti::frame_address(2));
     })
 }

Diff for: src/test/run-pass/check-static-slice.rs

@@ -28,14 +28,14 @@ static cf: isize = af[2];
 
 fn main () {
     let b: &[isize] = &[1, 2, 3];
-    assert!(ac == b);
-    assert!(ad == b);
-    assert!(af == b);
+    assert_eq!(ac, b);
+    assert_eq!(ad, b);
+    assert_eq!(af, b);
 
-    assert!(ca == 1);
-    assert!(cb == 2);
-    assert!(cc == 3);
-    assert!(cd == 1);
-    assert!(ce == 2);
-    assert!(cf == 3);
+    assert_eq!(ca, 1);
+    assert_eq!(cb, 2);
+    assert_eq!(cc, 3);
+    assert_eq!(cd, 1);
+    assert_eq!(ce, 2);
+    assert_eq!(cf, 3);
 }

Diff for: src/test/run-pass/class-impl-very-parameterized-trait.rs

@@ -104,7 +104,7 @@ impl<T> cat<T> {
 pub fn main() {
     let mut nyan: cat<String> = cat::new(0, 2, "nyan".to_string());
     for _ in 1_usize..5 { nyan.speak(); }
-    assert!(*nyan.find(&1).unwrap() == "nyan".to_string());
+    assert_eq!(*nyan.find(&1).unwrap(), "nyan".to_string());
     assert_eq!(nyan.find(&10), None);
     let mut spotty: cat<cat_type> = cat::new(2, 57, cat_type::tuxedo);
     for _ in 0_usize..6 { spotty.speak(); }

Diff for: src/test/run-pass/cmp-default.rs

@@ -13,6 +13,7 @@ use std::cmp::Ordering;
 
 // Test default methods in PartialOrd and PartialEq
 //
+#[derive(Debug)]
 struct Fool(bool);
 
 impl PartialEq for Fool {
@@ -74,8 +75,8 @@ pub fn main() {
     assert!(RevInt(1) >= RevInt(2));
     assert!(RevInt(1) >= RevInt(1));
 
-    assert!(Fool(true)  == Fool(false));
+    assert_eq!(Fool(true), Fool(false));
     assert!(Fool(true)  != Fool(true));
     assert!(Fool(false) != Fool(false));
-    assert!(Fool(false) == Fool(true));
+    assert_eq!(Fool(false), Fool(true));
 }

Diff for: src/test/run-pass/const-big-enum.rs

@@ -23,7 +23,7 @@ pub fn main() {
         _ => panic!()
     }
     match Y {
-        Foo::Bar(s) => assert!(s == 2654435769),
+        Foo::Bar(s) => assert_eq!(s, 2654435769),
         _ => panic!()
     }
     match Z {

Diff for: src/test/run-pass/const-enum-structlike.rs

@@ -19,6 +19,6 @@ static C: E = E::S1 { u: 23 };
 pub fn main() {
     match C {
         E::S0 { .. } => panic!(),
-        E::S1 { u } => assert!(u == 23)
+        E::S1 { u } => assert_eq!(u, 23)
     }
 }

Diff for: src/test/run-pass/const-enum-vec-index.rs

@@ -23,7 +23,7 @@ pub fn main() {
         _ => panic!()
     }
     match C1 {
-        E::V1(n) => assert!(n == 0xDEADBEE),
+        E::V1(n) => assert_eq!(n, 0xDEADBEE),
         _ => panic!()
     }
 
@@ -32,7 +32,7 @@ pub fn main() {
         _ => panic!()
     }
     match D1 {
-        E::V1(n) => assert!(n == 0xDEADBEE),
+        E::V1(n) => assert_eq!(n, 0xDEADBEE),
         _ => panic!()
     }
 }

Diff for: src/test/run-pass/const-enum-vec-ptr.rs

@@ -14,7 +14,7 @@ static C: &'static [E] = &[E::V0, E::V1(0xDEADBEE), E::V0];
 
 pub fn main() {
     match C[1] {
-        E::V1(n) => assert!(n == 0xDEADBEE),
+        E::V1(n) => assert_eq!(n, 0xDEADBEE),
         _ => panic!()
     }
     match C[2] {

Diff for: src/test/run-pass/const-enum-vector.rs

@@ -14,7 +14,7 @@ static C: [E; 3] = [E::V0, E::V1(0xDEADBEE), E::V0];
 
 pub fn main() {
     match C[1] {
-        E::V1(n) => assert!(n == 0xDEADBEE),
+        E::V1(n) => assert_eq!(n, 0xDEADBEE),
         _ => panic!()
     }
     match C[2] {