add JSONReader.Feature#UseDoubleForDecimals

Author: wenshao

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

@@ -2977,6 +2977,10 @@ public final Number getNumber() {
                             decimalStr + "E" + exponent);
                 }
 
+                if ((context.features & Feature.UseDoubleForDecimals.mask) != 0) {
+                    return decimal.doubleValue();
+                }
+
                 return decimal;
             }
             case JSON_TYPE_BIG_DEC: {
@@ -4562,8 +4566,14 @@ public enum Feature {
 
         /**
          * Feature that disables the support for single quote.
+         * @since 2.0.53
+         */
+        DisableSingleQuote(1L << 31L),
+
+        /**
+         * @since 2.0.53
          */
-        DisableSingleQuote(1 << 31);
+        UseDoubleForDecimals(1L << 32L);
 
         public final long mask;
 

fastjson1-compatible/src/main/java/com/alibaba/fastjson/parser/JSONScanner.java

@@ -113,7 +113,7 @@ public void config(Feature feature, boolean state) {
                 rawFeature = JSONReader.Feature.UseNativeObject;
                 break;
             case UseBigDecimal:
-                rawFeature = JSONReader.Feature.UseBigDecimalForDoubles;
+                rawFeature = JSONReader.Feature.UseDoubleForDecimals;
                 not = true;
                 break;
             case OrderedField:
@@ -166,7 +166,7 @@ public boolean isEnabled(Feature feature) {
                 rawFeature = JSONReader.Feature.UseNativeObject;
                 break;
             case UseBigDecimal:
-                return !reader.isEnabled(JSONReader.Feature.UseBigDecimalForDoubles);
+                return !reader.isEnabled(JSONReader.Feature.UseDoubleForDecimals);
             default:
                 break;
         }