fixed bug in altering partitioned tables

The issue was caused by using ObjectMapper for Array column types.

The following sequence of SQL statements would result in an exception:

> create table foo (id int, tag array(string)) partitioned by(id)
> insert into foo (id) values (1)
> alter table foo add column name string

CHANGES.txt

@@ -5,6 +5,9 @@ Changes for Crate
 Unreleased
 ==========
 
+ - Fixed an issue that prevented altering a partitioned table by adding a new
+   column if the table already contains an array column.
+
 2016/05/12 0.54.9
 =================
 

sql/src/main/java/org/elasticsearch/index/mapper/core/ArrayMapper.java

@@ -262,7 +262,11 @@ private void parseNull(ParseContext context) throws IOException {
 
     @Override
     public void merge(Mapper mergeWith, MergeContext mergeContext) throws MergeMappingException {
-        innerMapper.merge(mergeWith, mergeContext);
+        if (mergeWith instanceof ArrayMapper) {
+            innerMapper.merge(((ArrayMapper) mergeWith).innerMapper, mergeContext);
+        } else {
+            innerMapper.merge(mergeWith, mergeContext);
+        }
     }
 
     @Override

sql/src/test/java/io/crate/integrationtests/PartitionedTableIntegrationTest.java

@@ -1259,6 +1259,24 @@ public void testPartitionedTableNestedAllConstraintsRoundTrip() throws Exception
         assertEquals(1L, response.rowCount());
     }
 
+    @Test
+    public void testAlterPartitionedTableWithArrayInRootFields() {
+        execute("create table foo (a integer, b ARRAY(OBJECT)) partitioned by(a)");
+        ensureYellow();
+        execute("insert into foo (a) values (?)", new Object[]{1});
+        execute("refresh table foo");
+        ensureGreen();
+
+        execute("alter table foo add column c string");
+
+        execute("select column_name " +
+                "from information_schema.columns " +
+                "where schema_name = 'doc' and table_name = 'foo' " +
+                "order by column_name asc");
+
+        assertThat(TestingHelpers.printedTable(response.rows()), is("a\nb\nc\n"));
+    }
+
     @Test
     public void testAlterPartitionTable() throws Exception {
         execute("create table quotes (id integer, quote string, date timestamp) " +