Fix Timestamp borsh failed and Improve parity-scale-codec Timestamp (#688)

* refactor(ibc): clean up Cargo.toml and update timestamp implementation and tests.

* Refactor Timestamp's encoding to remove conditional implementation

* test: add serde test for timestamp module with parity-scale-codec feature

* Create 687-fix-borsh-timstamp-ser-der.md

Author: DaviRain-Su

.changelog/unreleased/features/687-fix-borsh-timstamp-ser-der.md

@@ -0,0 +1,2 @@
+- Timestamp ser and der failed on borsh feature
+  ([#687](https://github.com/cosmos/ibc-rs/issues/687))

crates/ibc/Cargo.toml

@@ -18,7 +18,7 @@ all-features = true
 
 [features]
 default = ["std"]
-std = [ 
+std = [
     "ibc-proto/std",
     "ics23/std",
     "serde/std",

crates/ibc/src/core/timestamp.rs

@@ -34,12 +34,7 @@ impl borsh::BorshSerialize for Timestamp {
         &self,
         writer: &mut W,
     ) -> borsh::maybestd::io::Result<()> {
-        let timestamp = if let Some(time) = self.time {
-            time.unix_timestamp_nanos()
-        } else {
-            // When the value in `Time` is `None` we give the timestamp a default value of 0
-            0
-        };
+        let timestamp = self.nanoseconds();
         borsh::BorshSerialize::serialize(&timestamp, writer)
     }
 }
@@ -58,13 +53,7 @@ impl borsh::BorshDeserialize for Timestamp {
 #[cfg(feature = "parity-scale-codec")]
 impl parity_scale_codec::Encode for Timestamp {
     fn encode_to<T: parity_scale_codec::Output + ?Sized>(&self, writer: &mut T) {
-        let timestamp = if let Some(time) = self.time {
-            time.unix_timestamp_nanos()
-        } else {
-            // When the value in `Time` is `None` we give the timestamp a default value of 0
-            0
-        };
-
+        let timestamp = self.nanoseconds();
         timestamp.encode_to(writer);
     }
 }
@@ -389,4 +378,22 @@ mod tests {
         let inner = res.unwrap();
         assert!(inner > sleep_duration);
     }
+
+    #[test]
+    #[cfg(feature = "borsh")]
+    fn test_timestamp_borsh_ser_der() {
+        use borsh::{BorshDeserialize, BorshSerialize};
+        let timestamp = Timestamp::now();
+        let encode_timestamp = timestamp.try_to_vec().unwrap();
+        let _ = Timestamp::try_from_slice(&encode_timestamp).unwrap();
+    }
+
+    #[test]
+    #[cfg(feature = "parity-scale-codec")]
+    fn test_timestamp_parity_scale_codec_ser_der() {
+        use parity_scale_codec::{Decode, Encode};
+        let timestamp = Timestamp::now();
+        let encode_timestamp = timestamp.encode();
+        let _ = Timestamp::decode(&mut encode_timestamp.as_slice()).unwrap();
+    }
 }