added MassChangeTests

main/src/com/google/refine/model/changes/MassChange.java

@@ -33,7 +33,9 @@ OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 
 package com.google.refine.model.changes;
 
- import java.io.IOException;
+import java.io.IOException;
+import com.google.common.collect.Lists;
+ 
 import java.io.LineNumberReader;
 import java.io.Writer;
 import java.util.ArrayList;
@@ -70,8 +72,8 @@ public class MassChange implements Change {
     @Override
     public void revert(Project project) {
         synchronized (project) {
-            for (int i = _changes.size() - 1; i >= 0; i--){
+            for (Change change : Lists.reverse(_changes)){
-                _changes.get(i).revert(project);
+                change.revert(project);
             }
             
             if (_updateRowContextDependencies) {

main/tests/server/src/com/google/refine/tests/model/changes/MassChangeTests.java

@@ -0,0 +1,67 @@
+
+package com.google.refine.tests.model.changes;
+
+import static org.testng.AssertJUnit.assertTrue;
+
+import java.io.File;
+import java.io.IOException;
+import java.util.ArrayList;
+import java.util.List;
+
+import org.slf4j.LoggerFactory;
+import org.testng.annotations.BeforeMethod;
+import org.testng.annotations.BeforeTest;
+import org.testng.annotations.Test;
+
+import com.google.refine.ProjectManager;
+import com.google.refine.ProjectMetadata;
+import com.google.refine.model.ModelException;
+import com.google.refine.model.Project;
+import com.google.refine.model.changes.CellAtRow;
+import com.google.refine.model.changes.ColumnAdditionChange;
+import com.google.refine.model.changes.MassChange;
+import com.google.refine.history.Change;
+import com.google.refine.io.FileProjectManager;
+import com.google.refine.tests.RefineTest;
+import com.google.refine.tests.util.TestUtils;
+
+public class MassChangeTests extends RefineTest {
+
+    Project project;
+
+    @Override
+    @BeforeTest
+    public void init() {
+        logger = LoggerFactory.getLogger(this.getClass());
+    }
+
+    @BeforeMethod
+    public void SetUp()
+            throws IOException, ModelException {
+        File dir = TestUtils.createTempDirectory("openrefine-test-workspace-dir");
+        FileProjectManager.initialize(dir);
+        project = new Project();
+        ProjectMetadata pm = new ProjectMetadata();
+        pm.setName("TNG Test Project");
+        ProjectManager.singleton.registerProject(project, pm);
+    }
+
+    /**
+     * Test case for #914 - Demonstrates MassChange revert doesn't work by
+     * adding two columns to a project with a MassChange and then reverting.
+     * Without the fix, column "a" will be removed before column "b", causing
+     * column "b" removal to fail because it won't be found at index 1 as
+     * expected.
+     */
+    @Test
+    public void testWrongReverseOrder()
+            throws Exception {
+        List<Change> changes = new ArrayList<Change>();
+        changes.add(new ColumnAdditionChange("a", 0, new ArrayList<CellAtRow>()));
+        changes.add(new ColumnAdditionChange("b", 1, new ArrayList<CellAtRow>()));
+        MassChange massChange = new MassChange(changes, false);
+        massChange.apply(project);
+        massChange.revert(project);
+        assertTrue(project.columnModel.columns.isEmpty());
+    }
+}