Fix assert usage in tests (#724)

Co-authored-by: Dusan Stanivukovic <[email protected]>
Co-authored-by: Nicholas Rodrigues Lordello <[email protected]>

ethcontract-common/src/bytecode.rs

@@ -60,9 +60,7 @@ impl Bytecode {
         S: AsRef<str>,
     {
         let name = name.as_ref();
-        if name.len() > 38 {
-            panic!("invalid library name for linking");
-        }
+        assert!(name.len() <= 38, "invalid library name for linking");
 
         // NOTE(nlordell): solc linking works by string search and replace of
         //   '__$name__..__' with the library address; see generated bytecode for

ethcontract-generate/src/util.rs

@@ -94,16 +94,18 @@ mod tests {
 
     #[test]
     fn parse_address_missing_prefix() {
-        if parse_address("0000000000000000000000000000000000000000").is_ok() {
-            panic!("parsing address not starting with 0x should fail");
-        }
+        assert!(
+            parse_address("0000000000000000000000000000000000000000").is_err(),
+            "parsing address not starting with 0x should fail"
+        );
     }
 
     #[test]
     fn parse_address_address_too_short() {
-        if parse_address("0x00000000000000").is_ok() {
-            panic!("parsing address not starting with 0x should fail");
-        }
+        assert!(
+            parse_address("0x00000000000000").is_err(),
+            "parsing address not starting with 0x should fail"
+        );
     }
 
     #[test]

ethcontract-mock/src/details/mod.rs

@@ -602,14 +602,13 @@ impl MockTransport {
         let tx = verify(&raw_tx.0, state.chain_id);
 
         let nonce = state.nonce.entry(tx.from).or_insert(0);
-        if *nonce != tx.nonce.as_u64() {
-            panic!(
-                "nonce mismatch for account {:#x}: expected {}, actual {}",
-                tx.from,
-                tx.nonce.as_u64(),
-                nonce
-            );
-        }
+        assert!(
+            *nonce == tx.nonce.as_u64(),
+            "nonce mismatch for account {:#x}: expected {}, actual {}",
+            tx.from,
+            tx.nonce.as_u64(),
+            nonce
+        );
         *nonce += 1;
 
         let contract = state.contract(tx.to);
@@ -717,9 +716,7 @@ impl Contract {
         //
         // We could support receive/fallback functions if data is empty.
 
-        if data.len() < 4 {
-            panic!("transaction has invalid call data");
-        }
+        assert!(data.len() >= 4, "transaction has invalid call data");
 
         let signature = H32::try_from(&data[0..4]).unwrap();
         let method = self.method(signature);
@@ -785,9 +782,10 @@ impl Method {
         index: usize,
         generation: usize,
     ) -> &mut Expectation<P, R> {
-        if generation != self.generation {
-            panic!("old expectations are not valid after checkpoint");
-        }
+        assert!(
+            generation == self.generation,
+            "old expectations are not valid after checkpoint"
+        );
 
         let expectation: &mut Expectation<P, R> = self
             .expectations

ethcontract-mock/src/details/parse.rs

@@ -90,8 +90,10 @@ impl Parser {
 
 impl Drop for Parser {
     fn drop(&mut self) {
-        if !std::thread::panicking() && self.current < self.args.len() {
-            panic!("too many arguments for rpc call {:?}", self.name);
-        }
+        assert!(
+            std::thread::panicking() || self.current >= self.args.len(),
+            "too many arguments for rpc call {:?}",
+            self.name
+        );
     }
 }

ethcontract-mock/src/details/sign.rs

@@ -22,13 +22,11 @@ pub fn verify(raw_tx: &[u8], node_chain_id: u64) -> Transaction {
         err();
     }
 
-    if res(rlp.at(3)).size() == 0 {
-        // TODO:
-        //
-        // We could support deployments via RPC calls by introducing
-        // something like `expect_deployment` method to `Mock` struct.
-        panic!("mock client does not support deploying contracts via transaction, use `Mock::deploy` instead");
-    }
+    // TODO:
+    //
+    // We could support deployments via RPC calls by introducing
+    // something like `expect_deployment` method to `Mock` struct.
+    assert!(res(rlp.at(3)).size() != 0, "mock client does not support deploying contracts via transaction, use `Mock::deploy` instead");
 
     let nonce: U256 = res(rlp.val_at(0));
     let gas_price: U256 = res(rlp.val_at(1));
@@ -46,9 +44,10 @@ pub fn verify(raw_tx: &[u8], node_chain_id: u64) -> Transaction {
         _ => panic!("invalid transaction signature, v value is out of range"),
     };
 
-    if chain_id != node_chain_id {
-        panic!("invalid transaction signature, chain id mismatch");
-    }
+    assert!(
+        chain_id == node_chain_id,
+        "invalid transaction signature, chain id mismatch"
+    );
 
     let msg_hash = {
         let mut rlp = rlp::RlpStream::new();

ethcontract/src/int.rs

@@ -28,9 +28,7 @@ fn twos_complement(u: U256) -> U256 {
 fn handle_overflow<T>((result, overflow): (T, bool)) -> T {
     #[cfg(debug_assertions)]
     {
-        if overflow {
-            panic!("overflow");
-        }
+        assert!(!overflow, "overflow");
     }
 
     let _ = overflow;
@@ -1708,9 +1706,7 @@ mod tests {
     #[test]
     #[cfg_attr(debug_assertions, should_panic)]
     fn div_euclid_overflow() {
-        // We only attempt to print here because of the must_use
-        // error: unused return value of `int::I256::div_euclid` that must be used
-        println!("{}", I256::MIN.div_euclid(-I256::one()));
+        let _ = I256::MIN.div_euclid(-I256::one());
     }
 
     #[test]