chore(nargo): add test for reading/writing inputs to fs (#996)

chore: add test for reading/writing inputs to fs

crates/nargo/src/cli/fs/inputs.rs

@@ -73,3 +73,66 @@ pub(crate) fn write_inputs_to_file<P: AsRef<Path>>(
 
     Ok(())
 }
+
+#[cfg(test)]
+mod tests {
+    use std::{collections::BTreeMap, vec};
+
+    use acvm::FieldElement;
+    use noirc_abi::{
+        input_parser::{Format, InputValue},
+        Abi, AbiParameter, AbiType, AbiVisibility,
+    };
+    use tempdir::TempDir;
+
+    use super::{read_inputs_from_file, write_inputs_to_file};
+    use crate::constants::VERIFIER_INPUT_FILE;
+
+    #[test]
+    fn write_and_read_recovers_inputs_and_return_value() {
+        let input_dir = TempDir::new("input_dir").unwrap().into_path();
+
+        // We purposefully test a simple ABI here as we're focussing on `fs`.
+        // Tests for serializing complex types should exist in `noirc_abi`.
+        let abi = Abi {
+            parameters: vec![
+                AbiParameter {
+                    name: "foo".into(),
+                    typ: AbiType::Field,
+                    visibility: AbiVisibility::Public,
+                },
+                AbiParameter {
+                    name: "bar".into(),
+                    typ: AbiType::String { length: 11 },
+                    visibility: AbiVisibility::Private,
+                },
+            ],
+            return_type: Some(AbiType::Field),
+
+            // Input serialization is only dependent on types, not position in witness map.
+            // Neither of these should be relevant so we leave them empty.
+            param_witnesses: BTreeMap::new(),
+            return_witnesses: Vec::new(),
+        };
+        let input_map = BTreeMap::from([
+            ("foo".to_owned(), InputValue::Field(42u128.into())),
+            ("bar".to_owned(), InputValue::String("hello world".to_owned())),
+        ]);
+        let return_value = Some(InputValue::Field(FieldElement::zero()));
+
+        write_inputs_to_file(
+            &input_map,
+            &return_value,
+            &input_dir,
+            VERIFIER_INPUT_FILE,
+            Format::Toml,
+        )
+        .unwrap();
+
+        let (loaded_inputs, loaded_return_value) =
+            read_inputs_from_file(input_dir, VERIFIER_INPUT_FILE, Format::Toml, &abi).unwrap();
+
+        assert_eq!(loaded_inputs, input_map);
+        assert_eq!(loaded_return_value, return_value);
+    }
+}

crates/noirc_abi/src/input_parser/mod.rs

@@ -10,8 +10,7 @@ use crate::{Abi, AbiType};
 /// This is what all formats eventually transform into
 /// For example, a toml file will parse into TomlTypes
 /// and those TomlTypes will be mapped to Value
-#[cfg_attr(test, derive(PartialEq))]
-#[derive(Debug, Clone, Serialize)]
+#[derive(Debug, Clone, Serialize, PartialEq)]
 pub enum InputValue {
     Field(FieldElement),
     Vec(Vec<FieldElement>),