impl: tail test

src/rule/collection.rs

@@ -6,6 +6,7 @@ mod init;
 mod last;
 mod reverse;
 mod skip;
+mod tail;
 
 pub use exists::*;
 pub use for_all::*;
@@ -15,3 +16,4 @@ pub use init::*;
 pub use last::*;
 pub use reverse::*;
 pub use skip::*;
+pub use tail::*;

src/rule/collection/tail.rs

@@ -0,0 +1,78 @@
+use crate::rule::{Rule, SkipFirst, SkipRule};
+use crate::Refined;
+use std::collections::VecDeque;
+
+/// A type that holds a value satisfying the `TailRule`
+pub type Tail<RULE, ITERABLE, ITEM> = Refined<TailRule<RULE, ITERABLE, ITEM>>;
+
+/// A type that holds a `Vec` value satisfying the `TailRule`
+pub type TailVec<RULE> = Tail<RULE, Vec<<RULE as Rule>::Item>, <RULE as Rule>::Item>;
+
+/// A type that holds a `VecDeque` value satisfying the `TailRule`
+pub type TailVecDeque<RULE> = Tail<RULE, VecDeque<<RULE as Rule>::Item>, <RULE as Rule>::Item>;
+
+/// A type that holds a `String` value satisfying the `TailRule`
+pub type TailString<RULE> = Tail<RULE, String, char>;
+
+/// Rule where the data in the collection satisfies the condition after skipping the first element
+pub type TailRule<RULE, ITERABLE, ITEM> = SkipRule<RULE, ITERABLE, SkipFirst<ITEM>>;
+
+/// Rule where the data in the `Vec` satisfies the condition after skipping the first element
+pub type TailVecRule<RULE> = TailRule<RULE, Vec<<RULE as Rule>::Item>, <RULE as Rule>::Item>;
+
+/// Rule where the data in the `VecDeque` satisfies the condition after skipping the first element
+pub type TailVecDequeRule<RULE> =
+    TailRule<RULE, VecDeque<<RULE as Rule>::Item>, <RULE as Rule>::Item>;
+
+/// Rule where the data in the `String` satisfies the condition after skipping the first element
+pub type TailStringRule<RULE> = TailRule<RULE, String, char>;
+
+#[cfg(test)]
+mod tests {
+    use crate::result::Error;
+    use crate::rule::{NonEmptyStringRule, TailVec};
+
+    #[test]
+    fn test_tail_valid() -> Result<(), Error<Vec<String>>> {
+        let table = vec![
+            (
+                vec!["hey".to_string(), "hello".to_string(), "world".to_string()],
+                vec!["hey".to_string(), "hello".to_string(), "world".to_string()],
+            ),
+            (
+                vec!["".to_string(), "hello".to_string(), "world".to_string()],
+                vec!["".to_string(), "hello".to_string(), "world".to_string()],
+            ),
+            (vec!["".to_string()], vec!["".to_string()]),
+            (vec![], vec![]),
+        ];
+
+        for (input, expected) in table {
+            let refined = TailVec::<NonEmptyStringRule>::new(input.clone())?;
+            assert_eq!(refined.into_value(), expected);
+        }
+
+        Ok(())
+    }
+
+    #[test]
+    fn test_tail_invalid() -> Result<(), Error<Vec<String>>> {
+        let table = vec![
+            vec!["hey".to_string(), "hello".to_string(), "".to_string()],
+            vec!["hey".to_string(), "".to_string(), "".to_string()],
+            vec!["".to_string(), "hello".to_string(), "".to_string()],
+            vec!["".to_string(), "".to_string(), "".to_string()],
+            vec!["hey".to_string(), "hello".to_string(), "".to_string()],
+            vec!["hey".to_string(), "".to_string(), "".to_string()],
+            vec!["".to_string(), "hello".to_string(), "".to_string()],
+            vec!["".to_string(), "".to_string(), "".to_string()],
+        ];
+
+        for input in table {
+            let refined = TailVec::<NonEmptyStringRule>::new(input.clone());
+            assert!(refined.is_err());
+        }
+
+        Ok(())
+    }
+}