1 files changed, 93 insertions, 0 deletions
diff --git a/vendor/mac/src/inspect.rs b/vendor/mac/src/inspect.rs
new file mode 100644
index 000000000..4fd8ce2ce
--- /dev/null
+++ b/vendor/mac/src/inspect.rs
@@ -0,0 +1,93 @@
+//! Inspect Macros
+
+/// Evaluates an expression, prints a stringified version of the expression
+/// along with the evaluated value, and then returns that value.
+///
+/// # Example
+///
+/// ```
+/// # #[macro_use] extern crate mac;
+///
+/// # fn main() {
+/// fn lcm_2_to_4() -> u32 {
+///     let mut i = 1;
+///     loop {
+///         if inspect!(i % 2, i % 3, i % 4) == (0, 0, 0) {
+///             return inspect!("done: i = " => i);
+///         }
+///         i += 1;
+///     }
+/// }
+/// assert_eq!(lcm_2_to_4(), 12);
+/// # }
+/// ```
+///
+/// Returns `12`, and prints the following to stdout:
+///
+/// ```ignore
+/// src/inspect.rs:94 - (i % 2, i % 3, i % 4) = (1, 1, 1)
+/// src/inspect.rs:94 - (i % 2, i % 3, i % 4) = (0, 2, 2)
+/// src/inspect.rs:94 - (i % 2, i % 3, i % 4) = (1, 0, 3)
+/// src/inspect.rs:94 - (i % 2, i % 3, i % 4) = (0, 1, 0)
+/// src/inspect.rs:94 - (i % 2, i % 3, i % 4) = (1, 2, 1)
+/// src/inspect.rs:94 - (i % 2, i % 3, i % 4) = (0, 0, 2)
+/// src/inspect.rs:94 - (i % 2, i % 3, i % 4) = (1, 1, 3)
+/// src/inspect.rs:94 - (i % 2, i % 3, i % 4) = (0, 2, 0)
+/// src/inspect.rs:94 - (i % 2, i % 3, i % 4) = (1, 0, 1)
+/// src/inspect.rs:94 - (i % 2, i % 3, i % 4) = (0, 1, 2)
+/// src/inspect.rs:94 - (i % 2, i % 3, i % 4) = (1, 2, 3)
+/// src/inspect.rs:94 - (i % 2, i % 3, i % 4) = (0, 0, 0)
+/// src/inspect.rs:95 - done: i = 12
+/// ```
+
+#[macro_export]
+macro_rules! inspect {
+    ($prefix:expr => $expr:expr) => {{
+        let val = $expr;
+        println!("{}:{} - {}{:?}", file!(), line!(), $prefix, val);
+        val
+    }};
+    ($expr:expr) => {
+        inspect!(concat!(stringify!($expr), " = ") => $expr)
+    };
+    ($prefix:expr => $($expr:expr),+) => {
+        inspect!($prefix => ($($expr),+))
+    };
+    ($($expr:expr),+) => {
+        inspect!(($($expr),+))
+    };
+}
+
+#[test]
+fn test_inspect() {
+    assert_eq!(inspect!("foo"), "foo");
+    assert_eq!(inspect!("" => "foo"), "foo");
+    assert_eq!(inspect!(1 + 2, 2 + 3, 3 + 4), (3, 5, 7));
+    assert_eq!(inspect!("" => 1 + 2, 2 + 3, 3 + 4), (3, 5, 7));
+
+    fn fib(n: u64) -> u64 {
+        inspect!("fib :: n = " => n);
+        inspect! { "ret = " => match n {
+            0 | 1 => n,
+            n => fib(n-1) + fib(n-2)
+        }}
+    }
+
+    fn fib_iter(n: u64) -> u64 {
+        inspect!("fib_iter :: n = " => n);
+        let (mut a, mut b) = (0, 1);
+        for _ in 0..n {
+            inspect!(a, b);
+            let tmp = b;
+            b += a;
+            a = tmp;
+        }
+        inspect!("ret = " => a)
+    }
+
+    assert_eq!(fib(4), 3);
+    assert_eq!(fib_iter(7), 13);
+
+    // Uncomment the following to see the output in `cargo test`.
+    // panic!()
+}