Fix #1940

Author: cowtowncoder

release-notes/CREDITS-2.x

@@ -753,3 +753,8 @@ Deblock Thomas (deblockt@github)
 lilei@venusgroup.com.cn:
   * Reported #1931: Two more `c3p0` gadgets to exploit default typing issue
    (2.9.5)
+
+Aniruddha Maru (maroux@github)
+  * Reported #1940: `Float` values with integer value beyond `int` lose precision if
+    bound to `long`
+   (2.9.5)

release-notes/VERSION-2.x

@@ -14,6 +14,9 @@ Project: jackson-databind
  (contributed by Deblock T)
 #1931: Two more `c3p0` gadgets to exploit default typing issue
  (reported by lilei@venusgroup.com.cn)
+#1940: `Float` values with integer value beyond `int` lose precision if
+  bound to `long`
+ (reported by Aniruddha M)
 
 2.9.4 (24-Jan-2018)
 
@@ -208,7 +211,7 @@ Project: jackson-databind
   `MapperFeature.ALLOW_COERCION_OF_SCALARS`
  (requested by magdel@github)
 
-2.8.11.1 (not yet released)
+2.8.11.1 (11-Feb-2018)
 
 #1872: `NullPointerException` in `SubTypeValidator.validateSubType` when
   validating Spring interface

src/main/java/com/fasterxml/jackson/databind/util/TokenBuffer.java

@@ -1637,8 +1637,7 @@ private final boolean _smallerThanLong(Number n) {
             return (n instanceof Integer) || (n instanceof Short) || (n instanceof Byte);
         }
 
-        /* 02-Jan-2017, tatu: Modified from method(s) in `ParserBase`
-         */
+        // 02-Jan-2017, tatu: Modified from method(s) in `ParserBase`
 
         protected int _convertNumberToInt(Number n) throws IOException
         {
@@ -1689,7 +1688,7 @@ protected long _convertNumberToLong(Number n) throws IOException
                 if (d < MIN_LONG_D || d > MAX_LONG_D) {
                     reportOverflowLong();
                 }
-                return (int) d;
+                return (long) d;
             } else if (n instanceof BigDecimal) {
                 BigDecimal big = (BigDecimal) n;
                 if (BD_MIN_LONG.compareTo(big) > 0 

src/test/java/com/fasterxml/jackson/databind/node/TestConversions.java

@@ -8,6 +8,7 @@
 
 import org.junit.Assert;
 
+import com.fasterxml.jackson.annotation.JsonTypeInfo;
 import com.fasterxml.jackson.core.*;
 import com.fasterxml.jackson.core.type.WritableTypeId;
 import com.fasterxml.jackson.databind.*;
@@ -70,7 +71,16 @@ static class Issue467TmpBean  {
 
         public Issue467TmpBean(int i) { x = i; }
     }
-    
+
+    static class Issue709Bean {
+        public byte[] data;
+    }
+
+    @JsonTypeInfo(use=JsonTypeInfo.Id.CLASS, include=JsonTypeInfo.As.PROPERTY, property="_class")
+    static class LongContainer1940 {
+        public Long longObj;
+    }
+
     /*
     /**********************************************************
     /* Unit tests
@@ -173,10 +183,6 @@ public void testBase64Text() throws Exception
         }
     }
 
-    static class Issue709Bean {
-        public byte[] data;
-    }
-    
     /**
      * Simple test to verify that byte[] values can be handled properly when
      * converting, as long as there is metadata (from POJO definitions).
@@ -288,5 +294,12 @@ public void testConversionOfTrees() throws Exception
         assertTrue("Expected Object, got "+tree.getNodeType(), tree.isBoolean());
         assertEquals(EXP, MAPPER.writeValueAsString(tree));
     }
-}
 
+    // [databind#1940]: losing of precision due to coercion
+    public void testBufferedLongViaCoercion() throws Exception {
+        long EXP = 1519348261000L;
+        JsonNode tree = MAPPER.readTree("{\"longObj\": "+EXP+".0, \"_class\": \""+LongContainer1940.class.getName()+"\"}");
+        LongContainer1940 obj = MAPPER.treeToValue(tree, LongContainer1940.class);
+        assertEquals(Long.valueOf(EXP), obj.longObj);
+    }
+}