Fix numeric precision loss in JSON parsing

The general purpose `jsonParse` utility was lossy when it comes to
numbers containing a decimal point.

This affected `json_parse` SQL function, `JSON` SQL type constructor and
connectors which use `jsonParse` to canonicalize JSON representation on
remote data read (e.g. PostgreSQL).

Author: findepi

core/trino-main/src/test/java/io/trino/type/TestArrayOperators.java

@@ -583,7 +583,7 @@ public void testJsonToArraySmoke()
 
         assertTrinoExceptionThrownBy(() -> assertions.expression("CAST(a AS array(INTEGER))")
                 .binding("a", "JSON '[1234567890123.456]'").evaluate())
-                .hasMessage("Cannot cast to array(integer). Out of range for integer: 1.234567890123456E12\n[1.234567890123456E12]")
+                .hasMessage("Cannot cast to array(integer). Out of range for integer: 1.234567890123456E12\n[1234567890123.456]")
                 .hasErrorCode(INVALID_CAST_ARGUMENT);
 
         assertThat(assertions.expression("CAST(a AS array(DECIMAL(10,5)))")
@@ -1082,11 +1082,10 @@ public void testCastJsonToArrayDecimal()
                 .matches("CAST(ARRAY[DECIMAL '12345.88'] AS ARRAY(DECIMAL(7,2)))");
 
         // array with large decimal
-        // TODO precision loss!
         assertThat(assertions.expression("cast(a as ARRAY(DECIMAL(38,8)))")
                 .binding("a", "JSON '[123456789012345678901234567890.12345678]'"))
                 .hasType(new ArrayType(createDecimalType(38, 8)))
-                .matches("CAST(ARRAY[DECIMAL '123456789012345680000000000000.00000000'] AS ARRAY(DECIMAL(38,8)))");
+                .matches("CAST(ARRAY[DECIMAL '123456789012345678901234567890.12345678'] AS ARRAY(DECIMAL(38,8)))");
 
         // non-array JSON should fail
         assertTrinoExceptionThrownBy(() -> assertions.expression("cast(a as ARRAY(DECIMAL(10,3)))")

core/trino-main/src/test/java/io/trino/type/TestJsonOperators.java

@@ -705,11 +705,10 @@ public void testCastToDecimal()
                 .hasType(createDecimalType(10, 3))
                 .isEqualTo(decimal("128.000", createDecimalType(10, 3)));
 
-        // TODO precision loss!
         assertThat(assertions.expression("cast(a as DECIMAL(38,8))")
                 .binding("a", "JSON '123456789012345678901234567890.12345678'"))
                 .hasType(createDecimalType(38, 8))
-                .isEqualTo(decimal("123456789012345680000000000000.00000000", createDecimalType(38, 8)));
+                .isEqualTo(decimal("123456789012345678901234567890.12345678", createDecimalType(38, 8)));
 
         assertThat(assertions.expression("cast(a as DECIMAL(38,8))")
                 .binding("a", "cast(DECIMAL '123456789012345678901234567890.12345678' as JSON)"))
@@ -796,10 +795,10 @@ public void testCastToBoolean()
                 .binding("a", "JSON '1e-324'"))
                 .isEqualTo(false);
 
-        // overflow
-        assertTrinoExceptionThrownBy(() -> assertions.expression("cast(a as BOOLEAN)")
-                .binding("a", "JSON '1e309'").evaluate())
-                .hasErrorCode(INVALID_CAST_ARGUMENT);
+        // overflow if parsed as double
+        assertThat(assertions.expression("cast(a as BOOLEAN)")
+                .binding("a", "JSON '1e309'"))
+                .isEqualTo(true);
 
         assertThat(assertions.expression("cast(a as BOOLEAN)")
                 .binding("a", "JSON 'true'"))

core/trino-main/src/test/java/io/trino/type/TestMapOperators.java

@@ -683,7 +683,7 @@ public void testJsonToMap()
 
         assertTrinoExceptionThrownBy(() -> assertions.expression("cast(a as MAP(VARCHAR, INTEGER))")
                 .binding("a", "JSON '{\"a\": 1234567890123.456}'").evaluate())
-                .hasMessage("Cannot cast to map(varchar, integer). Out of range for integer: 1.234567890123456E12\n{\"a\":1.234567890123456E12}")
+                .hasMessage("Cannot cast to map(varchar, integer). Out of range for integer: 1.234567890123456E12\n{\"a\":1234567890123.456}")
                 .hasErrorCode(INVALID_CAST_ARGUMENT);
 
         assertTrinoExceptionThrownBy(() -> assertions.expression("cast(a as MAP(BIGINT, BIGINT))")

lib/trino-plugin-toolkit/src/main/java/io/trino/plugin/base/util/JsonTypeUtil.java

@@ -36,6 +36,7 @@
 import java.util.StringJoiner;
 
 import static com.fasterxml.jackson.core.JsonFactory.Feature.CANONICALIZE_FIELD_NAMES;
+import static com.fasterxml.jackson.databind.DeserializationFeature.USE_BIG_DECIMAL_FOR_FLOATS;
 import static com.fasterxml.jackson.databind.SerializationFeature.ORDER_MAP_ENTRIES_BY_KEYS;
 import static com.google.common.base.Preconditions.checkState;
 import static io.trino.plugin.base.util.JsonUtils.jsonFactoryBuilder;
@@ -52,6 +53,7 @@ public final class JsonTypeUtil
     private static final JsonMapper SORTED_MAPPER = new JsonMapperProvider().get()
             .rebuild()
             .configure(ORDER_MAP_ENTRIES_BY_KEYS, true)
+            .configure(USE_BIG_DECIMAL_FOR_FLOATS, true)
             .build();
 
     private JsonTypeUtil() {}

lib/trino-plugin-toolkit/src/test/java/io/trino/plugin/base/util/TestJsonTypeUtil.java

@@ -77,8 +77,7 @@ void testJsonParseLargeNumber()
         assertThat(jsonParse(utf8Slice("12345678901234567890123456789012345678")).toStringUtf8())
                 .isEqualTo("12345678901234567890123456789012345678");
         assertThat(jsonParse(utf8Slice("123456789012345678901234567890.12345678")).toStringUtf8())
-                // TODO precision loss! Numbers are converted through floating-point instead of being preserved as strings
-                .isEqualTo("1.2345678901234568E29");
+                .isEqualTo("123456789012345678901234567890.12345678");
     }
 
     @Test