Ensure that empty TXT records always renders as ""

nresare · nresare · commit 6ed0fcf883ae · 2022-06-16T10:20:03.000+01:00
Instantiating an empty TXT record using Record.fromString() would previously render as a TXT without the empty string. Closes #254
diff --git a/src/main/java/org/xbill/DNS/TXTBase.java b/src/main/java/org/xbill/DNS/TXTBase.java
@@ -82,7 +82,9 @@ protected String rrToString() {
         sb.append(" ");
       }
     }
-    return sb.toString();
+    String s = sb.toString();
+    // always return at least an empty quoted String
+    return "".equals(s) ? "\"\"" : s;
   }
 
   /**
diff --git a/src/test/java/org/xbill/DNS/RecordTest.java b/src/test/java/org/xbill/DNS/RecordTest.java
@@ -912,4 +912,12 @@ void testSerializable() throws IOException {
       }
     }
   }
+
+  // https://github.com/dnsjava/dnsjava/issues/254
+  @Test
+  void testEmptyTXTSerialization() throws IOException {
+    Name recordName = Name.fromString("name.name.");
+    Record r = Record.fromString(recordName, Type.TXT, DClass.IN, 0, "", recordName);
+    assertEquals("name.name.\t\t0\tIN\tTXT\t\"\"", r.toString());
+  }
 }

Original file line number	Diff line number	Diff line change
`@@ -82,7 +82,9 @@ protected String rrToString() {`
`82`	`82`	`sb.append(" ");`
`83`	`83`	`}`
`84`	`84`	`}`
`85`		`- return sb.toString();`
	`85`	`+ String s = sb.toString();`
	`86`	`+ // always return at least an empty quoted String`
	`87`	`+ return "".equals(s) ? "\"\"" : s;`
`86`	`88`	`}`
`87`	`89`
`88`	`90`	`/**`
Original file line number	Diff line number	Diff line change
`@@ -912,4 +912,12 @@ void testSerializable() throws IOException {`
`912`	`912`	`}`
`913`	`913`	`}`
`914`	`914`	`}`
	`915`	`+`
	`916`	`+ // https://github.com/dnsjava/dnsjava/issues/254`
	`917`	`+ @Test`
	`918`	`+ void testEmptyTXTSerialization() throws IOException {`
	`919`	`+ Name recordName = Name.fromString("name.name.");`
	`920`	`+ Record r = Record.fromString(recordName, Type.TXT, DClass.IN, 0, "", recordName);`
	`921`	`+ assertEquals("name.name.\t\t0\tIN\tTXT\t\"\"", r.toString());`
	`922`	`+ }`
`915`	`923`	`}`