tidb_query: fix parse number to JSON

[lonng]

Signed-off-by: Lonng heng@lonng.org

What have you changed?

Fix parse string to JSON. According to TiDB implementation, all numbers will be treated as

func appendBinaryNumber(buf []byte, x json.Number) (TypeCode, []byte, error) {
	var typeCode TypeCode
	if strings.ContainsAny(string(x), "Ee.") {
		typeCode = TypeCodeFloat64
		f64, err := x.Float64()
		if err != nil {
			return typeCode, nil, errors.Trace(err)
		}
		buf = appendBinaryFloat64(buf, f64)
	} else {
		typeCode = TypeCodeInt64
		i64, err := x.Int64()
		if err != nil {
			typeCode = TypeCodeFloat64
			f64, err := x.Float64()
			if err != nil {
				return typeCode, nil, errors.Trace(err)
			}
			buf = appendBinaryFloat64(buf, f64)
		} else {
			buf = appendBinaryUint64(buf, uint64(i64))
		}
	}
	return typeCode, buf, nil
}

See playground: https://play.golang.org/p/Ps4nRxJykpr

What is the type of the changes?

Pick one of the following and delete the others:

• Bugfix (a change which fixes an issue)

How is the PR tested?

Please select the tests that you ran to verify your changes:

• Unit test

[lonng]

/test

[breezewish]

/merge

[sre-bot]

/run-all-tests

[sre-bot]

@lonng merge failed.

[lonng]

/test