Add support for exceptions

crates/format/src/case.rs

@@ -1,6 +1,10 @@
 use serde::Deserialize;
 
-use crate::{define_wrapper_type, input::Input, mode::Mode};
+use crate::{
+    define_wrapper_type,
+    input::{Expected, Input},
+    mode::Mode,
+};
 
 #[derive(Debug, Default, Deserialize, Clone, Eq, PartialEq)]
 pub struct Case {
@@ -9,6 +13,7 @@ pub struct Case {
     pub modes: Option<Vec<Mode>>,
     pub inputs: Vec<Input>,
     pub group: Option<String>,
+    pub expected: Option<Expected>,
 }
 
 define_wrapper_type!(
@@ -16,3 +21,21 @@ define_wrapper_type!(
     #[derive(Clone, Copy, Debug, PartialEq, Eq, PartialOrd, Ord, Hash)]
     CaseIdx(usize);
 );
+
+impl Case {
+    pub fn inputs_iterator(&self) -> impl Iterator<Item = Input> {
+        let inputs_len = self.inputs.len();
+        self.inputs
+            .clone()
+            .into_iter()
+            .enumerate()
+            .map(move |(idx, mut input)| {
+                if idx + 1 == inputs_len {
+                    input.expected = self.expected.clone();
+                    input
+                } else {
+                    input
+                }
+            })
+    }
+}