Write units tests

src/tests.rs

@@ -0,0 +1,57 @@
+use super::*;
+
+#[derive(Debug, PartialEq)]
+struct EvenUsize(usize);
+
+#[derive(Debug)]
+struct OddUsize;
+
+impl Vet for EvenUsize {
+    type VetError = OddUsize;
+    fn is_valid(&self) -> Result<(), Self::VetError> {
+        if self.0 % 2 == 0 {
+            Ok(())
+        } else {
+            Err(OddUsize)
+        }
+    }
+}
+
+#[test]
+fn vet_type() {
+    let foo = EvenUsize(2);
+    assert!(foo.is_valid().is_ok());
+
+    let foo = EvenUsize(3);
+    assert!(foo.is_valid().is_err());
+}
+
+#[test]
+fn vet_option() {
+    let foo = None::<EvenUsize>;
+    assert!(foo.is_valid().is_ok());
+
+    let foo = Some(EvenUsize(4));
+    assert!(foo.is_valid().is_ok());
+
+    let foo = Some(EvenUsize(5));
+    assert!(foo.is_valid().is_err());
+}
+
+#[test]
+#[cfg(feature = "alloc")]
+fn vet_vec() {
+    use alloc::{vec, vec::Vec};
+
+    let foo = Vec::<EvenUsize>::new();
+    assert!(foo.is_valid().is_ok());
+
+    let foo = vec![EvenUsize(8)];
+    assert!(foo.is_valid().is_ok());
+
+    let foo = vec![EvenUsize(7)];
+    assert!(foo.is_valid().is_err());
+
+    let foo = vec![EvenUsize(8), EvenUsize(7)];
+    assert!(foo.is_valid().is_err());
+}