/*
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance
* with the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.apache.pig.test;
import static junit.framework.Assert.assertEquals;
import static org.apache.pig.builtin.mock.Storage.resetData;
import static org.apache.pig.builtin.mock.Storage.tuple;
import static org.junit.Assert.fail;
import java.util.List;
import org.apache.pig.ExecType;
import org.apache.pig.PigServer;
import org.apache.pig.builtin.mock.Storage.Data;
import org.apache.pig.data.Tuple;
import org.apache.pig.impl.logicalLayer.FrontendException;
import org.junit.Test;
public class TestCase {
/**
* Verify that CASE statement without else branch works correctly.
* @throws Exception
*/
@Test
public void testNoElseBranch() throws Exception {
PigServer pigServer = new PigServer(ExecType.LOCAL);
Data data = resetData(pigServer);
data.set("foo",
tuple(1),
tuple(2),
tuple(3),
tuple(4),
tuple(5),
tuple(6),
tuple(7)
);
pigServer.registerQuery("A = LOAD 'foo' USING mock.Storage() AS (i:int);");
pigServer.registerQuery("B = FOREACH A GENERATE i, (" +
" CASE i % 5" +
" WHEN 0 THEN '5n'" +
" WHEN 1 THEN '5n+1'" +
" WHEN 2 THEN '5n+2'" +
" WHEN 3 THEN '5n+3'" +
" END" +
") AS s;");
pigServer.registerQuery("C = FILTER B BY s IS NOT NULL;");
pigServer.registerQuery("STORE C INTO 'bar' USING mock.Storage();");
List<Tuple> out = data.get("bar");
assertEquals(6, out.size());
assertEquals(tuple(1,"5n+1"), out.get(0));
assertEquals(tuple(2,"5n+2"), out.get(1));
assertEquals(tuple(3,"5n+3"), out.get(2));
assertEquals(tuple(5,"5n"), out.get(3));
assertEquals(tuple(6,"5n+1"), out.get(4));
assertEquals(tuple(7,"5n+2"), out.get(5));
}
/**
* Verify that CASE statement with else branch works correctly.
* @throws Exception
*/
@Test
public void testWithElseBranch() throws Exception {
PigServer pigServer = new PigServer(ExecType.LOCAL);
Data data = resetData(pigServer);
data.set("foo",
tuple(1),
tuple(2),
tuple(3),
tuple(4),
tuple(5),
tuple(6),
tuple(7)
);
pigServer.registerQuery("A = LOAD 'foo' USING mock.Storage() AS (i:int);");
pigServer.registerQuery("B = FOREACH A GENERATE i, (" +
" CASE i % 4" +
" WHEN 0 THEN '4n'" +
" WHEN 1 THEN '4n+1'" +
" WHEN 2 THEN '4n+2'" +
" ELSE '4n+3'" +
" END" +
");");
pigServer.registerQuery("STORE B INTO 'bar' USING mock.Storage();");
List<Tuple> out = data.get("bar");
assertEquals(7, out.size());
assertEquals(tuple(1,"4n+1"), out.get(0));
assertEquals(tuple(2,"4n+2"), out.get(1));
assertEquals(tuple(3,"4n+3"), out.get(2));
assertEquals(tuple(4,"4n"), out.get(3));
assertEquals(tuple(5,"4n+1"), out.get(4));
assertEquals(tuple(6,"4n+2"), out.get(5));
assertEquals(tuple(7,"4n+3"), out.get(6));
}
/**
* Verify that conditional CASE statement without else branch works correctly.
* @throws Exception
*/
@Test
public void testConditionalWithNoElse() throws Exception {
PigServer pigServer = new PigServer(ExecType.LOCAL);
Data data = resetData(pigServer);
data.set("foo",
tuple(1),
tuple(2),
tuple(3),
tuple(4),
tuple(5),
tuple(6),
tuple(7)
);
pigServer.registerQuery("A = LOAD 'foo' USING mock.Storage() AS (i:int);");
pigServer.registerQuery("B = FOREACH A GENERATE i, (" +
" CASE " +
" WHEN i % 5 == 0 THEN '5n'" + // Conditional expression in when branch
" WHEN i % 5 == 1 THEN '5n+1'" +
" WHEN i % 5 == 2 THEN '5n+2'" +
" WHEN i % 5 == 3 THEN '5n+3'" +
" END" +
") AS s;");
pigServer.registerQuery("C = FILTER B BY s IS NOT NULL;");
pigServer.registerQuery("STORE C INTO 'bar' USING mock.Storage();");
List<Tuple> out = data.get("bar");
assertEquals(6, out.size());
assertEquals(tuple(1,"5n+1"), out.get(0));
assertEquals(tuple(2,"5n+2"), out.get(1));
assertEquals(tuple(3,"5n+3"), out.get(2));
assertEquals(tuple(5,"5n"), out.get(3));
assertEquals(tuple(6,"5n+1"), out.get(4));
assertEquals(tuple(7,"5n+2"), out.get(5));
}
/**
* Verify that conditional CASE statement with else branch works correctly.
* @throws Exception
*/
@Test
public void testConditionalWithElse() throws Exception {
PigServer pigServer = new PigServer(ExecType.LOCAL);
Data data = resetData(pigServer);
data.set("foo",
tuple(1),
tuple(2),
tuple(3),
tuple(4),
tuple(5),
tuple(6),
tuple(7)
);
pigServer.registerQuery("A = LOAD 'foo' USING mock.Storage() AS (i:int);");
pigServer.registerQuery("B = FOREACH A GENERATE i, (" +
" CASE " +
" WHEN i % 4 == 0 THEN '4n'" + // Conditional expression in when branch
" WHEN i % 4 == 1 THEN '4n+1'" +
" WHEN i % 4 == 2 THEN '4n+2'" +
" ELSE '4n+3'" +
" END" +
");");
pigServer.registerQuery("STORE B INTO 'bar' USING mock.Storage();");
List<Tuple> out = data.get("bar");
assertEquals(7, out.size());
assertEquals(tuple(1,"4n+1"), out.get(0));
assertEquals(tuple(2,"4n+2"), out.get(1));
assertEquals(tuple(3,"4n+3"), out.get(2));
assertEquals(tuple(4,"4n"), out.get(3));
assertEquals(tuple(5,"4n+1"), out.get(4));
assertEquals(tuple(6,"4n+2"), out.get(5));
assertEquals(tuple(7,"4n+3"), out.get(6));
}
/**
* Verify that FrontendException is thrown when case expression is missing,
* and when branches do not contain conditional expressions.
* @throws Exception
*/
@Test(expected = FrontendException.class)
public void testMissingCaseExpression() throws Exception {
PigServer pigServer = new PigServer(ExecType.LOCAL);
Data data = resetData(pigServer);
data.set("foo",
tuple(1),
tuple(2),
tuple(3),
tuple(4),
tuple(5)
);
pigServer.registerQuery("A = LOAD 'foo' USING mock.Storage() AS (i:int);");
pigServer.registerQuery("B = FOREACH A GENERATE (" +
" CASE " + // No case expression
" WHEN 0 THEN '3n'" + // When expression is not conditional
" WHEN 1 THEN '3n+1'" +
" ELSE '3n+2'" +
" END" +
");");
pigServer.registerQuery("STORE B INTO 'bar' USING mock.Storage();");
fail("FrontendException must be thrown for invalid case statement");
}
/**
* Verify that FrontendException is thrown when when expression is missing.
* @throws Exception
*/
@Test(expected = FrontendException.class)
public void testMissingWhenExpression() throws Exception {
PigServer pigServer = new PigServer(ExecType.LOCAL);
Data data = resetData(pigServer);
data.set("foo",
tuple(1),
tuple(2),
tuple(3),
tuple(4),
tuple(5)
);
pigServer.registerQuery("A = LOAD 'foo' USING mock.Storage() AS (i:int);");
pigServer.registerQuery("B = FOREACH A GENERATE (" +
" CASE i % 3" +
" WHEN THEN '3n'" + // No when expression
" WHEN 1 THEN '3n+1'" +
" ELSE '3n+2'" +
" END" +
");");
pigServer.registerQuery("STORE B INTO 'bar' USING mock.Storage();");
fail("FrontendException must be thrown for invalid case statement");
}
/**
* Verify that FrontendException is thrown when when expression is missing.
* @throws Exception
*/
@Test(expected = FrontendException.class)
public void testMissingThenExpression() throws Exception {
PigServer pigServer = new PigServer(ExecType.LOCAL);
Data data = resetData(pigServer);
data.set("foo",
tuple(1),
tuple(2),
tuple(3),
tuple(4),
tuple(5)
);
pigServer.registerQuery("A = LOAD 'foo' USING mock.Storage() AS (i:int);");
pigServer.registerQuery("B = FOREACH A GENERATE (" +
" CASE i % 3" +
" WHEN 0 THEN " + // No then expression
" WHEN 1 THEN '3n+1'" +
" ELSE '3n+2'" +
" END" +
");");
pigServer.registerQuery("STORE B INTO 'bar' USING mock.Storage();");
fail("FrontendException must be thrown for invalid case statement");
}
/**
* Verify that FrontendException is thrown when when expression is missing.
* @throws Exception
*/
@Test(expected = FrontendException.class)
public void testMissingElseExpression() throws Exception {
PigServer pigServer = new PigServer(ExecType.LOCAL);
Data data = resetData(pigServer);
data.set("foo",
tuple(1),
tuple(2),
tuple(3),
tuple(4),
tuple(5)
);
pigServer.registerQuery("A = LOAD 'foo' USING mock.Storage() AS (i:int);");
pigServer.registerQuery("B = FOREACH A GENERATE (" +
" CASE i % 3" +
" WHEN 0 THEN '3n'" +
" WHEN 1 THEN '3n+1'" +
" ELSE " + // No else expression
" END" +
");");
pigServer.registerQuery("STORE B INTO 'bar' USING mock.Storage();");
fail("FrontendException must be thrown for invalid case statement");
}
}