From 9bac2832326d18bfc62d54c804f9b36d975b3001 Mon Sep 17 00:00:00 2001
From: "shaojin.wensj" <shaojin.wensj@alibaba-inc.com>
Date: Sun, 17 Mar 2024 15:48:48 +0800
Subject: [PATCH] double & float support input NaN, for issue #2309

---
 .../alibaba/fastjson2/JSONReaderUTF16.java    | 12 +++++++
 .../com/alibaba/fastjson2/JSONReaderUTF8.java | 12 +++++++
 .../fastjson2/issues_2300/Issue2309.java      | 34 +++++++++++++++++++
 3 files changed, 58 insertions(+)
 create mode 100644 core/src/test/java/com/alibaba/fastjson2/issues_2300/Issue2309.java

diff --git a/core/src/main/java/com/alibaba/fastjson2/JSONReaderUTF16.java b/core/src/main/java/com/alibaba/fastjson2/JSONReaderUTF16.java
index ed955a9409..f50f76a086 100644
--- a/core/src/main/java/com/alibaba/fastjson2/JSONReaderUTF16.java
+++ b/core/src/main/java/com/alibaba/fastjson2/JSONReaderUTF16.java
@@ -2802,6 +2802,12 @@ public final double readDoubleValue() {
                 doubleValue = 0;
                 value = true;
                 ch = offset == end ? EOI : chars[offset++];
+            } else if (ch == 'N' && chars[offset] == 'a' && chars[offset + 1] == 'N') {
+                valid = true;
+                offset += 2;
+                doubleValue = Double.NaN;
+                value = true;
+                ch = offset == end ? EOI : chars[offset++];
             } else if (ch == '{' && quote == 0) {
                 valid = true;
                 this.ch = ch;
@@ -3068,6 +3074,12 @@ public final float readFloatValue() {
                 floatValue = 0;
                 value = true;
                 ch = offset == end ? EOI : chars[offset++];
+            } else if (ch == 'N' && chars[offset] == 'a' && chars[offset + 1] == 'N') {
+                offset += 2;
+                valid = true;
+                value = true;
+                floatValue = Float.NaN;
+                ch = offset == end ? EOI : chars[offset++];
             } else if (ch == '{' && quote == 0) {
                 valid = true;
                 this.ch = ch;
diff --git a/core/src/main/java/com/alibaba/fastjson2/JSONReaderUTF8.java b/core/src/main/java/com/alibaba/fastjson2/JSONReaderUTF8.java
index 2dd9d1c3e4..b57eb6199a 100644
--- a/core/src/main/java/com/alibaba/fastjson2/JSONReaderUTF8.java
+++ b/core/src/main/java/com/alibaba/fastjson2/JSONReaderUTF8.java
@@ -3947,6 +3947,12 @@ public final double readDoubleValue() {
                 doubleValue = 0;
                 value = true;
                 ch = offset == end ? EOI : bytes[offset++];
+            } else if (ch == 'N' && bytes[offset] == 'a' && bytes[offset + 1] == 'N') {
+                valid = true;
+                offset += 2;
+                doubleValue = Double.NaN;
+                value = true;
+                ch = offset == end ? EOI : bytes[offset++];
             } else if (ch == '{' && quote == 0) {
                 valid = true;
                 this.ch = (char) ch;
@@ -4213,6 +4219,12 @@ public final float readFloatValue() {
                 floatValue = 0;
                 value = true;
                 ch = offset == end ? EOI : chars[offset++];
+            } else if (ch == 'N' && chars[offset] == 'a' && chars[offset + 1] == 'N') {
+                offset += 2;
+                valid = true;
+                value = true;
+                floatValue = Float.NaN;
+                ch = offset == end ? EOI : chars[offset++];
             } else if (ch == '{' && quote == 0) {
                 valid = true;
                 this.ch = (char) ch;
diff --git a/core/src/test/java/com/alibaba/fastjson2/issues_2300/Issue2309.java b/core/src/test/java/com/alibaba/fastjson2/issues_2300/Issue2309.java
new file mode 100644
index 0000000000..8b5140aea9
--- /dev/null
+++ b/core/src/test/java/com/alibaba/fastjson2/issues_2300/Issue2309.java
@@ -0,0 +1,34 @@
+package com.alibaba.fastjson2.issues_2300;
+
+import com.alibaba.fastjson2.JSON;
+import org.junit.jupiter.api.Test;
+
+import java.nio.charset.StandardCharsets;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+
+public class Issue2309 {
+    @Test
+    public void test() {
+        String str = "{\"value\":NaN}";
+        assertEquals(Double.NaN, JSON.parseObject(str.getBytes(StandardCharsets.UTF_8), Bean.class).value);
+        assertEquals(Double.NaN, JSON.parseObject(str.toCharArray(), Bean.class).value);
+        assertEquals(Double.NaN, JSON.parseObject(str, Bean.class).value);
+    }
+
+    public static class Bean {
+        public Double value;
+    }
+
+    @Test
+    public void testFloat() {
+        String str = "{\"value\":NaN}";
+        assertEquals(Float.NaN, JSON.parseObject(str.getBytes(StandardCharsets.UTF_8), Bean1.class).value);
+        assertEquals(Float.NaN, JSON.parseObject(str.toCharArray(), Bean1.class).value);
+        assertEquals(Float.NaN, JSON.parseObject(str, Bean1.class).value);
+    }
+
+    public static class Bean1 {
+        public Float value;
+    }
+}