FIX: applied history drops were not recognized (#1422)

src/main/java/io/ebeaninternal/dbmigration/model/PendingDrops.java

@@ -3,6 +3,7 @@ package io.ebeaninternal.dbmigration.model;
 import io.ebeaninternal.dbmigration.migration.ChangeSet;
 import io.ebeaninternal.dbmigration.migration.ChangeSetType;
 import io.ebeaninternal.dbmigration.migration.DropColumn;
+import io.ebeaninternal.dbmigration.migration.DropHistoryTable;
 import io.ebeaninternal.dbmigration.migration.DropTable;
 import io.ebeaninternal.dbmigration.migration.Migration;
 
@@ -207,10 +208,26 @@ public class PendingDrops {
 
         } else if (pendingDrop instanceof DropTable && dropTableIn((DropTable) pendingDrop, appliedDrops)) {
           iterator.remove();
+
+        } else if (pendingDrop instanceof DropHistoryTable && dropHistoryTableIn((DropHistoryTable) pendingDrop, appliedDrops)) {
+          iterator.remove();
+
         }
       }
     }
 
+    /**
+     * Return true if the pendingDrop is contained in the appliedDrops.
+     */
+    private boolean dropHistoryTableIn(DropHistoryTable pendingDrop, ChangeSet appliedDrops) {
+      for (Object o : appliedDrops.getChangeSetChildren()) {
+        if (o instanceof DropHistoryTable && sameHistoryTable(pendingDrop, (DropHistoryTable) o)) {
+          return true;
+        }
+      }
+      return false;
+    }
+
     /**
      * Return true if the pendingDrop is contained in the appliedDrops.
      */
@@ -235,6 +252,13 @@ public class PendingDrops {
       return false;
     }
 
+    /**
+     * Return true if the DropHistoryTable match by base-table name.
+     */
+    private boolean sameHistoryTable(DropHistoryTable pendingDrop, DropHistoryTable o) {
+      return pendingDrop.getBaseTable().equals(o.getBaseTable());
+    }
+
     /**
      * Return true if the DropTable match by table name.
      */