fix reference detection does not work well when deserializing to JSON…

…Object ,for issue #2180

core/src/main/java/com/alibaba/fastjson2/JSONReader.java

@@ -2127,6 +2127,25 @@ public void read(Map object, long features) {
                 }
             }
 
+            if (isReference()) {
+                String reference = readReference();
+                Object value = null;
+                if ("..".equals(reference)) {
+                    value = map;
+                } else {
+                    JSONPath jsonPath;
+                    try {
+                        jsonPath = JSONPath.of(reference);
+                    } catch (Exception ignored) {
+                        map.put(name, new JSONObject().fluentPut("$ref", reference));
+                        continue;
+                    }
+                    addResolveTask(map, name, jsonPath);
+                }
+                map.put(name, value);
+                continue;
+            }
+
             comma = false;
             Object value;
             switch (ch) {

core/src/test/java/com/alibaba/fastjson2/issues_2100/Issue2180.java

@@ -0,0 +1,65 @@
+package com.alibaba.fastjson2.issues_2100;
+
+import com.alibaba.fastjson2.JSON;
+import com.alibaba.fastjson2.JSONObject;
+import com.alibaba.fastjson2.JSONWriter;
+import lombok.EqualsAndHashCode;
+import lombok.Getter;
+import lombok.Setter;
+import lombok.ToString;
+import lombok.experimental.Accessors;
+import org.junit.jupiter.api.Test;
+
+import static org.junit.jupiter.api.Assertions.*;
+
+/**
+ * @author 张治保
+ * @since 2024/1/13
+ */
+public class Issue2180 {
+    @Getter
+    @Setter
+    @ToString
+    @EqualsAndHashCode
+    @Accessors(chain = true)
+    public static class Balance {
+        private Double amount;
+        private String currency;
+    }
+
+    @Getter
+    @Setter
+    @EqualsAndHashCode
+    @ToString
+    @Accessors(chain = true)
+    public static class Recovery {
+        private String name;
+        private Balance balance;
+        private Balance balance2;
+        private Balance recovery;
+    }
+
+    @Test
+    public void refTest() {
+        Balance usd = new Balance()
+                .setAmount(100.12)
+                .setCurrency("USD");
+        Recovery recovery = new Recovery()
+                .setName("hello")
+                .setBalance(usd)
+                .setBalance2(usd)
+                .setRecovery(usd);
+        String jsonString = JSON.toJSONString(recovery, JSONWriter.Feature.ReferenceDetection);
+        //完全相等 （在 JSONObject 中是完全相等的两个对象）
+        JSONObject jsonObject = JSON.parseObject(jsonString);
+        assertSame(jsonObject.get("balance"), jsonObject.get("balance2"));
+        assertSame(jsonObject.get("balance"), jsonObject.get("recovery"));
+        //原数据转成 jsonObject 然后转为对应类型 这里不完全相等，
+        //todo 使用JSONObject 转换之后不完全相等(不是同一个对象) 可优化
+        Recovery recovery2 = jsonObject.to(Recovery.class);
+        assertEquals(recovery2, recovery);
+        //原数据转换 完全相等
+        Recovery recovery3 = JSON.parseObject(jsonString, Recovery.class);
+        assertEquals(recovery3, recovery);
+    }
+}

core/src/test/java/com/alibaba/fastjson2/v1issues/issue_3900/Issue3922.java

@@ -1,16 +1,16 @@
 package com.alibaba.fastjson2.v1issues.issue_3900;
 
 import com.alibaba.fastjson2.JSONObject;
+import org.json.JSONException;
 import org.junit.jupiter.api.Test;
-
-import static org.junit.jupiter.api.Assertions.assertEquals;
+import org.skyscreamer.jsonassert.JSONAssert;
 
 public class Issue3922 {
     @Test
-    public void test_for_issue3922() {
+    public void test_for_issue3922() throws JSONException {
         String jsonString = "{\"this0\":{\"$ref\":\"1\"}}";
         JSONObject jsonObject = JSONObject.parseObject(jsonString, JSONObject.class);
         JSONObject innerObject = (JSONObject) jsonObject.get("this0");
-        assertEquals("{\"$ref\":\"1\"}", innerObject.toString());
+        JSONAssert.assertEquals("{\"$ref\":\"1\"}", innerObject.toString(), true);
     }
 }