Add test showing fix of #4917 (via jackson-core) (#4931)

Author: cowtowncoder

release-notes/VERSION-2.x

@@ -8,6 +8,8 @@ Project: jackson-databind
 
 #4787: Wrong `String.format()` in `StdDelegatingDeserializer` hides actual error
  (reported by @Horus1337)
+#4917: `BigDecimal` deserialization issue when using `@JsonCreator`
+ (reported by @dbachdev)
 
 2.17.3 (01-Nov-2024)
 

src/test/java/com/fasterxml/jackson/databind/deser/jdk/JDKNumberDeserTest.java

@@ -82,6 +82,34 @@ static class NestedBigDecimalHolder2784 {
         public BigDecimalHolder2784 holder;
     }
 
+    static class DeserializationIssue4917 {
+        public DecimalHolder4917 decimalHolder;
+        public double number;
+    }
+
+    static class DeserializationIssue4917V2 {
+        public DecimalHolder4917 decimalHolder;
+        public int number;
+    }
+
+    static class DeserializationIssue4917V3 {
+        public BigDecimal decimal;
+        public double number;
+    }
+
+    static class DecimalHolder4917 {
+        public BigDecimal value;
+
+        private DecimalHolder4917(BigDecimal value) {
+            this.value = value;
+        }
+
+        @JsonCreator(mode = JsonCreator.Mode.DELEGATING)
+        static DecimalHolder4917 of(BigDecimal value) {
+            return new DecimalHolder4917(value);
+        }
+    }
+
     /*
     /**********************************************************************
     /* Helper classes, serializers/deserializers/resolvers
@@ -386,4 +414,35 @@ public void testBigDecimalUnwrapped() throws Exception
         NestedBigDecimalHolder2784 result = mapper.readValue(JSON, NestedBigDecimalHolder2784.class);
         assertEquals(new BigDecimal("5.00"), result.holder.value);
     }
+
+    // [databind#4917]    
+    @Test
+    public void bigDecimal4917() throws Exception
+    {
+        DeserializationIssue4917 issue = MAPPER.readValue(
+                a2q("{'decimalHolder':100.00,'number':50}"),
+                DeserializationIssue4917.class);
+        assertEquals(new BigDecimal("100.00"), issue.decimalHolder.value);
+        assertEquals(50.0, issue.number);
+    }
+
+    @Test
+    public void bigDecimal4917V2() throws Exception
+    {
+        DeserializationIssue4917V2 issue = MAPPER.readValue(
+                a2q("{'decimalHolder':100.00,'number':50}"),
+                DeserializationIssue4917V2.class);
+        assertEquals(new BigDecimal("100.00"), issue.decimalHolder.value);
+        assertEquals(50, issue.number);
+    }
+
+    @Test
+    public void bigDecimal4917V3() throws Exception
+    {
+        DeserializationIssue4917V3 issue = MAPPER.readValue(
+                a2q("{'decimal':100.00,'number':50}"),
+                DeserializationIssue4917V3.class);
+        assertEquals(new BigDecimal("100.00"), issue.decimal);
+        assertEquals(50, issue.number);
+    }
 }