Merge pull request #135 from erosb/const-schema-tostring

adding missing ConstSchema#decribePropertiesTo() method

Author: erosb

core/src/main/java/org/everit/json/schema/ConstSchema.java

@@ -2,6 +2,8 @@
 
 import static org.everit.json.schema.EnumSchema.toJavaValue;
 
+import org.everit.json.schema.internal.JSONPrinter;
+
 public class ConstSchema extends Schema {
 
     public static class ConstSchemaBuilder extends Schema.Builder<ConstSchema> {
@@ -29,6 +31,11 @@ protected ConstSchema(ConstSchemaBuilder builder) {
         this.permittedValue = toJavaValue(builder.permittedValue);
     }
 
+    @Override void describePropertiesTo(JSONPrinter writer) {
+        writer.key("const");
+        writer.value(this.permittedValue);
+    }
+
     @Override void accept(Visitor visitor) {
         visitor.visitConstSchema(this);
     }

core/src/test/java/org/everit/json/schema/ConstSchemaTest.java

@@ -1,6 +1,7 @@
 package org.everit.json.schema;
 
 import static org.everit.json.schema.TestSupport.loadAsV6;
+import static org.junit.Assert.assertEquals;
 
 import org.json.JSONArray;
 import org.json.JSONObject;
@@ -56,6 +57,27 @@ public void successWithObject() {
         testSuccess(new JSONObject("{\"a\":\"b\", \"b\":\"a\"}"));
     }
 
+    @Test
+    public void toStringTest() {
+        ConstSchema subject = ConstSchema.builder().permittedValue(true).build();
+        String actual = subject.toString();
+        assertEquals("{\"const\":true}", actual);
+    }
+
+    @Test
+    public void toStringWithNull() {
+        ConstSchema subject = ConstSchema.builder().permittedValue(null).build();
+        String actual = subject.toString();
+        assertEquals("{\"const\":null}", actual);
+    }
+
+    @Test
+    public void toStringWithObject() {
+        ConstSchema subject = ConstSchema.builder().permittedValue(new JSONObject("{\"a\":2}")).build();
+        String actual = subject.toString();
+        assertEquals("{\"const\":{\"a\":2}}", actual);
+    }
+
     @Test
     public void failureWithObject() {
         testFailure(new JSONObject("{}"), new JSONObject("{\"a\":null}"));