the metadata parser

Signed-off-by: Cyrill Leutwiler <bigcyrill@hotmail.com>

crates/format/src/input.rs

@@ -0,0 +1,77 @@
+use alloy_json_abi::Function;
+use alloy_primitives::U256;
+use serde::{Deserialize, de::Deserializer};
+
+/// Specify how the contract is called.
+#[derive(Debug, Default, Clone, Eq, PartialEq)]
+pub enum Method {
+    /// Initiate a deploy transaction, calling contracts constructor.
+    ///
+    /// Indicated by `#deployer`.
+    Deployer,
+    /// Does not calculate and insert a function selector.
+    ///
+    /// Indicated by `#fallback`.
+    #[default]
+    Fallback,
+    /// Call the public function with this selector.
+    ///
+    /// Calculates the selector if neither deployer or fallback matches.
+    Function([u8; 4]),
+}
+
+#[derive(Clone, Debug, Default, Deserialize, Eq, PartialEq)]
+pub struct Input {
+    instance: String,
+    #[serde(deserialize_with = "deserialize_method")]
+    method: Method,
+    #[serde(deserialize_with = "deserialize_calldata")]
+    calldata: Vec<u8>,
+    expected: Option<Vec<String>>,
+}
+
+fn deserialize_calldata<'de, D>(deserializer: D) -> Result<Vec<u8>, D::Error>
+where
+    D: Deserializer<'de>,
+{
+    let calldata_strings: Vec<String> = Vec::deserialize(deserializer)?;
+    let mut result = Vec::with_capacity(calldata_strings.len() * 32);
+
+    for calldata_string in &calldata_strings {
+        match calldata_string.parse::<U256>() {
+            Ok(parsed) => result.extend_from_slice(&parsed.to_be_bytes::<32>()),
+            Err(error) => {
+                return Err(serde::de::Error::custom(&format!(
+                    "parsing U256 {calldata_string} error: {error}"
+                )));
+            }
+        };
+    }
+
+    Ok(result)
+}
+
+fn deserialize_method<'de, D>(deserializer: D) -> Result<Method, D::Error>
+where
+    D: Deserializer<'de>,
+{
+    Ok(match String::deserialize(deserializer)?.as_str() {
+        "#deployer" => Method::Deployer,
+        "#fallback" => Method::Fallback,
+        signature => {
+            let signature = if signature.ends_with(')') {
+                signature.to_string()
+            } else {
+                format!("{signature}()")
+            };
+            match Function::parse(&signature) {
+                Ok(function) => Method::Function(function.selector().0),
+                Err(error) => {
+                    return Err(serde::de::Error::custom(&format!(
+                        "parsing function signature '{signature}' error: {error}"
+                    )));
+                }
+            }
+        }
+    })
+}