e - Added tests to show discrepancies when handling XML output by Jackson.

approvaltests-tests/pom.xml

@@ -104,6 +104,11 @@
             <artifactId>jackson-databind</artifactId>
             <version>2.16.1</version>
         </dependency>
+        <dependency>
+            <groupId>com.fasterxml.jackson.dataformat</groupId>
+            <artifactId>jackson-dataformat-xml</artifactId>
+            <version>2.16.1</version>
+        </dependency>
         <dependency>
             <groupId>org.apache.camel</groupId>
             <artifactId>camel-xstream</artifactId>

approvaltests-tests/src/test/java/org/approvaltests/Parse1InputTest.java

@@ -22,6 +22,7 @@ void testWithTypesTransformersAndBoth()
         """;
     ParseInput.from(expected).withTypes(Integer.class).verifyAll(Integer::toBinaryString);
     ParseInput.from(expected).transformTo(Integer::parseInt).verifyAll(Integer::toBinaryString);
-    ParseInput.from(expected).withTypes(String.class).transformTo(Integer::parseInt).verifyAll(Integer::toBinaryString);
+    ParseInput.from(expected).withTypes(String.class).transformTo(Integer::parseInt)
+        .verifyAll(Integer::toBinaryString);
   }
 }

approvaltests-tests/src/test/java/org/approvaltests/Parse2InputTest.java

@@ -8,12 +8,12 @@ public class Parse2InputTest
   void testWithTypesTransformersAndBoth()
   {
     var expected = """
-      1,2.2 -> 2.2
-      1,3.3 -> 3.3
-      """;
+        1,2.2 -> 2.2
+        1,3.3 -> 3.3
+        """;
     ParseInput.from(expected).withTypes(Integer.class, Double.class).verifyAll(t -> t.getFirst() * t.getSecond());
     // TODO: continue here
-//    ParseInput.from(expected).transformTo(Integer::parseInt).verifyAll(Integer::toBinaryString);
-//    ParseInput.from(expected).withTypes(String.class).transformTo(Integer::parseInt).verifyAll(Integer::toBinaryString);
+    //    ParseInput.from(expected).transformTo(Integer::parseInt).verifyAll(Integer::toBinaryString);
+    //    ParseInput.from(expected).withTypes(String.class).transformTo(Integer::parseInt).verifyAll(Integer::toBinaryString);
   }
 }

approvaltests-tests/src/test/java/org/approvaltests/writers/ApprovalXmlWriterTest.java

@@ -1,10 +1,16 @@
 package org.approvaltests.writers;
 
+import com.fasterxml.jackson.core.JsonProcessingException;
+import com.fasterxml.jackson.databind.ObjectWriter;
+import com.fasterxml.jackson.dataformat.xml.XmlMapper;
 import org.approvaltests.Approvals;
 import org.approvaltests.core.Options;
 import org.approvaltests.scrubbers.RegExScrubber;
+import org.junit.jupiter.api.Assertions;
 import org.junit.jupiter.api.Test;
 
+import static com.fasterxml.jackson.dataformat.xml.ser.ToXmlGenerator.Feature.WRITE_XML_DECLARATION;
+
 public class ApprovalXmlWriterTest
 {
   @Test
@@ -36,4 +42,36 @@ public void invalidXml()
     Approvals.verifyXml("<xml><hello/><start>hi</xml>");
     System.err.println("Note: The previous xml error (</start>) is expected ");
   }
+  @Test
+  void xmlOutputByJacksonIsHandledCorrectly() throws JsonProcessingException
+  {
+    ObjectWriter objectWriter = new XmlMapper().configure(WRITE_XML_DECLARATION, true).writer();
+    String jacksonXml = objectWriter.writeValueAsString(new JacksonTestPOJO());
+    String approvalsWriterXml = ApprovalXmlWriter.prettyPrint(jacksonXml, 2);
+    Assertions.assertEquals(jacksonXml, approvalsWriterXml);
+  }
+  @Test
+  void xmlOutputByJacksonIsHandledCorrectlyWhenPrettyPrintingIsEnabled() throws JsonProcessingException
+  {
+    ObjectWriter objectWriter = new XmlMapper().configure(WRITE_XML_DECLARATION, true)
+        .writerWithDefaultPrettyPrinter();
+    String jacksonXml = objectWriter.writeValueAsString(new JacksonTestPOJO());
+    String approvalsWriterXml = ApprovalXmlWriter.prettyPrint(jacksonXml, 2);
+    Assertions.assertEquals(jacksonXml, approvalsWriterXml);
+  }
+  private static class JacksonTestPOJO
+  {
+    public String getSomeText()
+    {
+      return "Some text";
+    }
+    public String getSomeTextWithAmpersand()
+    {
+      return "Some more text & some more";
+    }
+    public String getEmoji()
+    {
+      return "😸";
+    }
+  }
 }