1 files changed, 82 insertions, 0 deletions
diff --git a/tests/ui/consts/control-flow/basics.rs b/tests/ui/consts/control-flow/basics.rs
new file mode 100644
index 00000000000..02e5501f10c
--- /dev/null
+++ b/tests/ui/consts/control-flow/basics.rs
@@ -0,0 +1,82 @@
+// Test basic functionality of control flow in a const context.
+
+// run-pass
+
+const X: u32 = 4;
+const Y: u32 = 5;
+
+const ABS_DIFF: u32 = if X < Y {
+    Y - X
+} else {
+    X - Y
+};
+
+const fn abs_diff(a: u32, b: u32) -> u32 {
+    match (a, b) {
+        (big, little) if big > little => big - little,
+        (little, big) => big - little,
+    }
+}
+
+const fn gcd(a: u32, b: u32) -> u32 {
+    if b == 0 {
+        return a;
+    }
+
+    gcd(b, a % b)
+}
+
+const fn fib(n: u64) -> u64 {
+    if n == 0 {
+        return 0;
+    }
+
+    let mut fib = (0, 1);
+    let mut i = 1;
+    while i < n {
+        fib = (fib.1, fib.0 + fib.1);
+        i += 1;
+    }
+
+    fib.1
+}
+
+const fn is_prime(n: u64) -> bool {
+    if n % 2 == 0 {
+        return false;
+    }
+
+    let mut div = 3;
+    loop {
+        if n % div == 0 {
+            return false;
+        }
+
+        if div * div > n {
+            return true;
+        }
+
+        div += 2;
+    }
+}
+
+macro_rules! const_assert {
+    ($expr:expr) => {
+        const _: () = assert!($expr);
+        assert!($expr);
+    }
+}
+
+fn main() {
+    const_assert!(abs_diff(4, 5) == abs_diff(5, 4));
+    const_assert!(ABS_DIFF == abs_diff(5, 4));
+
+    const_assert!(gcd(48, 18) == 6);
+    const_assert!(gcd(18, 48) == 6);
+
+    const_assert!(fib(2) == 1);
+    const_assert!(fib(8) == 21);
+
+    const_assert!(is_prime(113));
+    const_assert!(!is_prime(117));
+}