migrate version only if newer pattern

contracts/distribution/dao-rewards-distributor/Cargo.toml

@@ -29,6 +29,7 @@ cw-utils = { workspace = true }
 dao-hooks = { workspace = true }
 dao-interface = { workspace = true }
 dao-voting = { workspace = true }
+semver = { workspace = true }
 thiserror = { workspace = true }
 
 [dev-dependencies]

contracts/distribution/dao-rewards-distributor/src/contract.rs

@@ -9,6 +9,7 @@ use cw20::{Cw20ReceiveMsg, Denom};
 use cw_storage_plus::Bound;
 use cw_utils::{must_pay, nonpayable, Duration, Expiration};
 use dao_interface::voting::InfoResponse;
+use semver::Version;
 
 use std::ops::Add;
 
@@ -592,6 +593,12 @@ fn query_distributions(
 
 #[cfg_attr(not(feature = "library"), entry_point)]
 pub fn migrate(deps: DepsMut, _env: Env, _msg: MigrateMsg) -> Result<Response, ContractError> {
-    set_contract_version(deps.storage, CONTRACT_NAME, CONTRACT_VERSION)?;
+    let version: Version = CONTRACT_VERSION.parse()?;
+    let storage_version: Version = get_contract_version(deps.storage)?.version.parse()?;
+
+    if storage_version < version {
+        set_contract_version(deps.storage, CONTRACT_NAME, CONTRACT_VERSION)?;
+    }
+
     Ok(Response::default())
 }

contracts/distribution/dao-rewards-distributor/src/error.rs

@@ -22,6 +22,9 @@ pub enum ContractError {
     #[error(transparent)]
     Payment(#[from] PaymentError),
 
+    #[error("semver parsing error: {0}")]
+    SemVer(String),
+
     #[error("Invalid CW20")]
     InvalidCw20 {},
 
@@ -55,3 +58,9 @@ pub enum ContractError {
     #[error("Cannot update emission rate because this distribution has accumulated the maximum rewards. Start a new distribution with the new emission rate instead. (Overflow: {err})")]
     DistributionHistoryTooLarge { err: String },
 }
+
+impl From<semver::Error> for ContractError {
+    fn from(err: semver::Error) -> Self {
+        Self::SemVer(err.to_string())
+    }
+}