rust: add type aliases for certain ffi types

bindings/rust/evmc-vm/src/lib.rs

@@ -9,9 +9,11 @@
 //! This crate documents how to use certain data types.
 
 mod container;
+mod types;
 
 pub use container::EvmcContainer;
 pub use evmc_sys as ffi;
+pub use types::*;
 
 pub trait EvmcVm {
     fn init() -> Self;

bindings/rust/evmc-vm/src/types.rs

@@ -0,0 +1,37 @@
+use evmc_sys as ffi;
+
+/// EVMC address
+pub type Address = ffi::evmc_address;
+
+/// EVMC 32 bytes value (used for hashes)
+pub type Bytes32 = ffi::evmc_bytes32;
+
+/// EVMC big-endian 256-bit integer
+pub type Uint256 = ffi::evmc_uint256be;
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    // These tests check for Default, PartialEq and Clone traits.
+    #[test]
+    fn address_smoke_test() {
+        let a = ffi::evmc_address::default();
+        let b = Address::default();
+        assert_eq!(a.clone(), b.clone());
+    }
+
+    #[test]
+    fn bytes32_smoke_test() {
+        let a = ffi::evmc_bytes32::default();
+        let b = Bytes32::default();
+        assert_eq!(a.clone(), b.clone());
+    }
+
+    #[test]
+    fn uint26be_smoke_test() {
+        let a = ffi::evmc_uint256be::default();
+        let b = Uint256::default();
+        assert_eq!(a.clone(), b.clone());
+    }
+}