/**
* Copyright (c) 2008-2012, http://www.snakeyaml.org
*
* Licensed 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.yaml.snakeyaml.types;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import org.yaml.snakeyaml.DumperOptions;
import org.yaml.snakeyaml.DumperOptions.FlowStyle;
import org.yaml.snakeyaml.Yaml;
import org.yaml.snakeyaml.nodes.Node;
import org.yaml.snakeyaml.nodes.Tag;
import org.yaml.snakeyaml.representer.Represent;
import org.yaml.snakeyaml.representer.Representer;
/**
* @see http://yaml.org/type/null.html
*/
public class NullTagTest extends AbstractTest {
public void testNull() {
assertNull("Got: '" + load("---\n") + "'", load("---\n"));
assertNull(load("---\n..."));
assertNull(load("---\n...\n"));
assertNull(load("\n"));
assertNull(load(""));
assertNull(load(" "));
assertNull(load("~"));
assertNull(load("---\n~"));
assertNull(load("null"));
assertNull(load("Null"));
assertNull(load("NULL"));
assertNull(getMapValue("empty:\n", "empty"));
assertNull(getMapValue("canonical: ~", "canonical"));
assertNull(getMapValue("english: null", "english"));
assertNull(getMapValue("english: Null", "english"));
assertNull(getMapValue("english: NULL", "english"));
assertEquals("null key", getMapValue("~: null key\n", null));
}
@SuppressWarnings("unchecked")
public void testSequenceNull() {
String input = "---\n# This sequence has five\n# entries, two have values.\nsparse:\n - ~\n - 2nd entry\n -\n - 4th entry\n - Null\n";
List<String> parsed = (List<String>) getMapValue(input, "sparse");
assertEquals(5, parsed.size());
assertNull(parsed.get(0));
assertEquals("2nd entry", parsed.get(1));
assertNull("Got: '" + parsed.get(2) + "'", parsed.get(2));
assertEquals("4th entry", parsed.get(3));
assertNull(parsed.get(4));
}
public void testNullInMap() {
String input = "key1: null\n~: value1";
Map<String, Object> parsed = getMap(input);
assertEquals(2, parsed.size());
assertTrue(parsed.containsKey(null));
Object value1 = parsed.get(null);
assertEquals("value1", value1);
//
assertNull(parsed.get("key1"));
//
assertFalse(getMap("key2: value2").containsKey(null));
}
public void testNullShorthand() {
assertNull(getMapValue("nothing: !!null null", "nothing"));
}
public void testNullTag() {
assertNull(getMapValue("nothing: !<tag:yaml.org,2002:null> null", "nothing"));
}
public void testNullOut() {
String output = dump(null);
assertEquals("null\n", output);
}
public void testNullOutAsEmpty() {
Yaml yaml = new Yaml(new NullRepresenter());
String output = yaml.dump(null);
assertEquals("", output);
}
/**
* test flow style
*/
public void testNullOutAsEmpty2() {
Yaml yaml = new Yaml(new NullRepresenter());
Map<String, String> map = new HashMap<String, String>();
map.put("aaa", "foo");
map.put("bbb", null);
String output = yaml.dump(map);
assertEquals("{aaa: foo, bbb: !!null ''}\n", output);
}
/**
* test block style
*/
public void testBoolOutAsEmpty3() {
DumperOptions options = new DumperOptions();
options.setDefaultFlowStyle(FlowStyle.BLOCK);
Yaml yaml = new Yaml(new NullRepresenter(), options);
Map<String, String> map = new HashMap<String, String>();
map.put("aaa", "foo");
map.put("bbb", null);
String output = yaml.dump(map);
assertEquals("aaa: foo\nbbb:\n", output);
}
private class NullRepresenter extends Representer {
public NullRepresenter() {
super();
// null representer is exceptional and it is stored as an instance
// variable.
this.nullRepresenter = new RepresentNull();
}
private class RepresentNull implements Represent {
public Node representData(Object data) {
// possible values are here http://yaml.org/type/null.html
return representScalar(Tag.NULL, "");
}
}
}
public void testNoAnchors() {
List<String> list = new ArrayList<String>(3);
list.add(null);
list.add("value");
list.add(null);
Yaml yaml = new Yaml();
String output = yaml.dump(list);
assertEquals("Null values must not get anchors and aliases.", "[null, value, null]\n",
output);
}
}