Rollup merge of rust-lang#139889 - spencer3035:clean-ui-tests-3-of-n, r=jieyouxu

Clean UI tests 3 of n

Cleaned up 2 tests in `tests/ui/numbers-arithemetic` to be more useful. One for each commit. I can squash these into one commit when approved.

Related Issues:
rust-lang#73494
rust-lang#133895

r? jieyouxu

Author: matthiaskrgr

tests/ui/numbers-arithmetic/int.rs

@@ -0,0 +1,25 @@
+//! Tests basic `isize` functionality
+
+//@ run-pass
+
+pub fn main() {
+    // Literal matches assignment type
+    let a: isize = 42isize;
+    // Literal cast
+    let b: isize = 42 as isize;
+    // Literal type inference from assignment type
+    let c: isize = 42;
+    // Assignment type inference from literal (and later comparison)
+    let d = 42isize;
+    // Function return value type inference
+    let e = return_val();
+
+    assert_eq!(a, b);
+    assert_eq!(a, c);
+    assert_eq!(a, d);
+    assert_eq!(a, e);
+}
+
+fn return_val() -> isize {
+    42
+}

tests/ui/numbers-arithmetic/isize-base.rs

@@ -0,0 +1,25 @@
+//! Tests basic `usize` functionality
+
+//@ run-pass
+
+pub fn main() {
+    // Literal matches assignment type
+    let a: usize = 42usize;
+    // Literal cast
+    let b: usize = 42 as usize;
+    // Literal type inference from assignment type
+    let c: usize = 42;
+    // Assignment type inference from literal (and later comparison)
+    let d = 42usize;
+    // Function return value type inference
+    let e = return_val();
+
+    assert_eq!(a, b);
+    assert_eq!(a, c);
+    assert_eq!(a, d);
+    assert_eq!(a, e);
+}
+
+fn return_val() -> usize {
+    42
+}