#44 Normalizer attempt

json-unit-core/src/main/java/net/javacrumbs/jsonunit/core/Option.java

@@ -50,6 +50,7 @@ public enum Option {
      */
     IGNORING_VALUES,
 
+    REPORTING_DIFFERENCE_AS_STRING,
     /**
      * Stops comparison at the first difference. Can bring performance boots to use-cases that do not need the full list of all differences.
      */

json-unit-core/src/main/java/net/javacrumbs/jsonunit/core/internal/Diff.java

@@ -21,6 +21,7 @@
 import static net.javacrumbs.jsonunit.core.Option.IGNORING_EXTRA_ARRAY_ITEMS;
 import static net.javacrumbs.jsonunit.core.Option.IGNORING_EXTRA_FIELDS;
 import static net.javacrumbs.jsonunit.core.Option.IGNORING_VALUES;
+import static net.javacrumbs.jsonunit.core.Option.REPORTING_DIFFERENCE_AS_STRING;
 import static net.javacrumbs.jsonunit.core.Option.TREATING_NULL_AS_ABSENT;
 import static net.javacrumbs.jsonunit.core.internal.ClassUtils.isClassPresent;
 import static net.javacrumbs.jsonunit.core.internal.DifferenceContextImpl.differenceContext;
@@ -34,6 +35,7 @@
 import static net.javacrumbs.jsonunit.core.internal.JsonUtils.quoteIfNeeded;
 import static net.javacrumbs.jsonunit.core.internal.Node.KeyValue;
 import static net.javacrumbs.jsonunit.core.internal.Node.NodeType;
+import static net.javacrumbs.jsonunit.core.internal.Normalizer.toNormalizedString;
 
 import java.math.BigDecimal;
 import java.util.ArrayList;
@@ -55,6 +57,7 @@
 import net.javacrumbs.jsonunit.core.internal.ArrayComparison.ComparisonResult;
 import net.javacrumbs.jsonunit.core.internal.ArrayComparison.NodeWithIndex;
 import net.javacrumbs.jsonunit.core.listener.Difference;
+import org.opentest4j.AssertionFailedError;
 
 /**
  * Compares JSON structures. Mainly for internal use, the API might be more volatile than the rest.
@@ -720,7 +723,11 @@ public void failIfDifferent() {
 
     public void failIfDifferent(String message) {
         if (!similar()) {
-            throw createException(message, differences);
+            if (!configuration.getOptions().contains(REPORTING_DIFFERENCE_AS_STRING)) {
+                throw createException(message, differences);
+            } else {
+                throw new AssertionFailedError("JSONs are different", toNormalizedString(expectedRoot), toNormalizedString(actualRoot)); //FIXME: paths
+            }
         }
     }
 

json-unit-core/src/main/java/net/javacrumbs/jsonunit/core/internal/Normalizer.java

@@ -0,0 +1,49 @@
+package net.javacrumbs.jsonunit.core.internal;
+
+import static java.util.Comparator.comparing;
+
+import java.util.Iterator;
+import java.util.Spliterators;
+import java.util.stream.Stream;
+import java.util.stream.StreamSupport;
+import net.javacrumbs.jsonunit.core.internal.Node.KeyValue;
+
+class Normalizer {
+
+    private static int depth = 2;
+
+    static String toNormalizedString(Node node) {
+        StringBuilder sb = new StringBuilder();
+        normalize(node, sb, 0);
+        return sb.toString();
+    }
+
+    private static void normalize(Node node, StringBuilder sb, int indent) {
+        switch (node.getNodeType()) {
+            case OBJECT -> {
+                addIndent(sb, indent);
+                sb.append("{\n");
+                stream(node.fields()).sorted(comparing(KeyValue::getKey)).forEach(keyValue -> {
+                    addIndent(sb, indent + depth);
+                    sb.append('"').append(keyValue.getKey()).append("\": ");
+                    normalize(keyValue.getValue(), sb, indent + depth);
+                    sb.append(",\n");
+                });
+                addIndent(sb, indent);
+                sb.append("}");
+            }
+            case STRING -> sb.append('\"').append(node).append('"');
+            default -> sb.append(node);
+        }
+    }
+
+    private static void addIndent(StringBuilder sb, int indent) {
+        for (int i = 0; i < indent; i++) {
+            sb.append(' ');
+        }
+    }
+
+    private static <T> Stream<T> stream(Iterator<T> iterator) {
+        return StreamSupport.stream(Spliterators.spliteratorUnknownSize(iterator, 0), false);
+    }
+}

tests/test-base/src/main/java/net/javacrumbs/jsonunit/test/base/AbstractAssertJTest.java

@@ -54,6 +54,7 @@
 import net.javacrumbs.jsonunit.test.base.AbstractJsonAssertTest.DivisionMatcher;
 import org.hamcrest.Matcher;
 import org.junit.jupiter.api.Disabled;
+import org.junit.jupiter.api.Nested;
 import org.junit.jupiter.api.Test;
 import org.opentest4j.AssertionFailedError;
 import org.opentest4j.MultipleFailuresError;
@@ -2303,6 +2304,16 @@ void shouldFailFast() {
                     """);
     }
 
+    @Nested
+    class ReportAsString {
+        @Test
+        void shouldSortMapKeys() {
+            assertThatJson("{\"a\": {\"c\": 1}, \"b\": 3}")
+                .when(Option.REPORTING_DIFFERENCE_AS_STRING)
+                .isEqualTo("{\"b\": 1, \"a\": {\"c\": 2}}");
+        }
+    }
+
     private static final String json =
             """
         {