[Snowflake Connector] Add tests for connector's SQL overrides.

Author: paolomorandini

dumper/app/src/test/java/com/google/edwmigration/dumper/application/dumper/connector/snowflake/SnowflakeMetadataConnectorTest.java

@@ -34,6 +34,8 @@
 import java.util.List;
 import java.util.Map;
 import javax.annotation.Nonnull;
+import org.apache.commons.lang3.ArrayUtils;
+import org.apache.commons.lang3.StringUtils;
 import org.junit.Assert;
 import org.junit.Assume;
 import org.junit.Test;
@@ -154,10 +156,35 @@ public void connector_generatesExpectedSql() throws IOException {
     }
   }
 
-  private static Map<String, String> collectSqlStatements() throws IOException {
+  @Test
+  public void connector_generatesExpectedSql_withQueryOverrides() throws IOException {
+    Map<String, String> actualSqls =
+        collectSqlStatements("-Dsnowflake.metadata.columns.query=SQL_OVERRIDE");
+
+    Assert.assertEquals("SQL_OVERRIDE", actualSqls.get("columns-au.csv"));
+    Assert.assertEquals("SQL_OVERRIDE", actualSqls.get("columns.csv"));
+  }
+
+  @Test
+  public void connector_generatesExpectedSql_withWhereOverrides() throws IOException {
+    Map<String, String> actualSqls =
+        collectSqlStatements("-Dsnowflake.metadata.columns.where=SQL_OVERRIDE");
+
+    // TODO: should be endsWith("WHERE SQL_OVERRIDE")
+    Assert.assertTrue(
+        actualSqls.get("columns-au.csv").endsWith("WHERE DELETED IS NULL WHERE SQL_OVERRIDE"));
+    // TODO: should be 1
+    Assert.assertEquals(2, StringUtils.countMatches(actualSqls.get("columns-au.csv"), " WHERE "));
+
+    Assert.assertTrue(actualSqls.get("columns.csv").endsWith("WHERE SQL_OVERRIDE"));
+    Assert.assertEquals(1, StringUtils.countMatches(actualSqls.get("columns.csv"), " WHERE "));
+  }
+
+  private static Map<String, String> collectSqlStatements(String... extraArgs) throws IOException {
     List<Task<?>> tasks = new ArrayList<>();
     SnowflakeMetadataConnector connector = new SnowflakeMetadataConnector();
-    connector.addTasksTo(tasks, new ConnectorArguments("--connector", connector.getName()));
+    String[] args = ArrayUtils.addAll(new String[] {"--connector", connector.getName()}, extraArgs);
+    connector.addTasksTo(tasks, new ConnectorArguments(args));
     return tasks.stream()
         .filter(t -> t instanceof JdbcSelectTask)
         .map(t -> (JdbcSelectTask) t)