fix(ecstore): guard free-version decommission conflicts

crates/ecstore/src/core/pools.rs

@@ -2640,8 +2640,12 @@ fn determine_decommission_final_state(items_failed: usize, was_cancelled: bool)
     }
 }
 
-fn decommission_remaining_version_count(total_versions: usize, expired: usize) -> usize {
-    total_versions.saturating_sub(expired)
+fn decommission_remaining_version_count(versions: &[rustfs_filemeta::FileInfo], expired: usize) -> usize {
+    versions
+        .iter()
+        .filter(|version| !version.tier_free_version())
+        .count()
+        .saturating_sub(expired)
 }
 
 fn should_skip_decommission_delete_marker(
@@ -3954,7 +3958,7 @@ impl ECStore {
                 continue;
             }
 
-            let remaining_versions = decommission_remaining_version_count(fivs.versions.len(), expired);
+            let remaining_versions = decommission_remaining_version_count(&fivs.versions, expired);
             if should_skip_decommission_delete_marker(version, remaining_versions, replication_config.is_some()) {
                 //
                 decommissioned += 1;
@@ -4419,6 +4423,39 @@ impl ECStore {
         .await
     }
 
+    #[cfg(test)]
+    pub(crate) async fn decommission_entry_for_test_with_bucket_incarnation(
+        self: &Arc<Self>,
+        idx: usize,
+        entry: MetaCacheEntry,
+        bucket: String,
+        set: Arc<SetDisks>,
+    ) -> Result<()> {
+        let expected_bucket_incarnation_id = if is_meta_bucketname(&bucket) {
+            None
+        } else {
+            Some(self.bucket_incarnation_id_from_disk(&bucket).await?)
+        };
+        self.decommission_entry(
+            CancellationToken::new(),
+            idx,
+            OffsetDateTime::now_utc(),
+            entry,
+            bucket,
+            set,
+            None,
+            None,
+            None,
+            expected_bucket_incarnation_id,
+        )
+        .await
+    }
+
+    #[cfg(test)]
+    pub(crate) async fn check_after_decommission_for_test(self: &Arc<Self>, idx: usize) -> Result<()> {
+        self.check_after_decommission(idx).await
+    }
+
     #[tracing::instrument(skip(self, rx))]
     async fn decommission_pool(
         self: &Arc<Self>,
@@ -5459,13 +5496,6 @@ mod tests {
         assert_eq!(determine_decommission_final_state(0, true), DecommissionFinalState::Failed);
     }
 
-    #[test]
-    fn decommission_remaining_version_count_excludes_only_expired_versions() {
-        assert_eq!(decommission_remaining_version_count(1, 0), 1);
-        assert_eq!(decommission_remaining_version_count(2, 1), 1);
-        assert_eq!(decommission_remaining_version_count(1, 1), 0);
-    }
-
     #[test]
     fn lifecycle_action_removes_data_movement_version_rejects_delete_marker_action() {
         assert!(!lifecycle_action_removes_data_movement_version(IlmAction::DeleteAction));