Feature/mixnet contract ci (#562)

* Fixed constant not updated in error macros

* Fixed clippy warning

* Attempt at adding mixnet contract to CI

.github/workflows/mixnet_contract.yml

@@ -0,0 +1,43 @@
+name: Mixnet Contract
+
+on: [push, pull_request]
+
+jobs:
+  ci:
+    # since it's going to be compiled into wasm, there's absolutely
+    # no point in running CI on different OS-es
+    runs-on: ubuntu-latest
+    continue-on-error: ${{ matrix.rust == 'nightly' }}
+    strategy:
+      matrix:
+        rust: [ stable, beta, nightly ]
+    steps:
+      - uses: actions/checkout@v2
+
+      - uses: actions-rs/toolchain@v1
+        with:
+          profile: minimal
+          toolchain: ${{ matrix.rust }}
+          target: wasm32-unknown-unknown
+          override: true
+          components: rustfmt, clippy
+
+      - uses: actions-rs/cargo@v1
+        with:
+          command: build
+          args: --manifest-path contracts/mixnet/Cargo.toml --target wasm32-unknown-unknown
+
+      - uses: actions-rs/cargo@v1
+        with:
+          command: test
+          args: --manifest-path contracts/mixnet/Cargo.toml
+
+      - uses: actions-rs/cargo@v1
+        with:
+          command: fmt
+          args: --manifest-path contracts/mixnet/Cargo.toml -- --check
+
+      - uses: actions-rs/cargo@v1
+        with:
+          command: clippy
+          args: --manifest-path contracts/mixnet/Cargo.toml -- -D warnings

contracts/mixnet/src/error.rs

@@ -30,9 +30,9 @@ pub enum ContractError {
     #[error("Unauthorized")]
     Unauthorized {},
 
-    #[error("Wrong coin denomination, you must send {}", STAKE_DENOM)]
+    #[error("Wrong coin denomination, you must send {}", DENOM)]
     WrongDenom {},
 
-    #[error("No coin was sent for the bonding, you must send {}", STAKE_DENOM)]
+    #[error("No coin was sent for the bonding, you must send {}", DENOM)]
     NoBondFound,
 }

contracts/mixnet/src/queries.rs

@@ -30,7 +30,7 @@ pub fn query_mixnodes_paged(
         .into_iter()
         .map(|item| item.1)
         .collect::<Vec<_>>();
-    let start_next_after = last_node_owner(&nodes);
+    let start_next_after = nodes.last().map(|node| node.owner().clone());
 
     let response = PagedResponse::new(nodes, limit, start_next_after);
     Ok(response)
@@ -90,13 +90,6 @@ fn calculate_start_value(
     })
 }
 
-fn last_node_owner(nodes: &[MixNodeBond]) -> Option<HumanAddr> {
-    match nodes.last() {
-        None => None,
-        Some(node) => Some(node.owner().clone()),
-    }
-}
-
 #[cfg(test)]
 mod tests {
     use super::*;