Patch float with trailing zero for JSON and add useFloatWithTrailingZero flag

[chenhuiyeh]

This pull request enables support for MySQL 8+ for retaining trailing zeros in floating-point numbers in JSON format. This is achieved through the addition of the useFloatWithTrailingZero setting option within the go-mysql library. Note this only works with MySQL version 8 onwards.

A patch addressing this feature was initially applied in ghostferry PR #368. This current PR seeks to integrate these updates into the upstream codebase to extend functionality for users and projects relying on this library.

This change is part of the broader initiative referenced in ghostferry PR #384.

[dveeden]

It would be good to add some tests and a description or an issue link.

[lance6716]

Hi, please fix the CI. And I'll take a look after you remove the draft status of PR.

[lance6716]

Hi, do you need some help?

[chenhuiyeh]

I was away, will be picking this up today. I'll reach out if I have any questions. Thank you

…

On Tue, Jun 3, 2025 at 2:57 AM lance6716 ***@***.***> wrote: *lance6716* left a comment (go-mysql-org/go-mysql#1038) <#1038 (comment)> Hi, do you need some help? — Reply to this email directly, view it on GitHub <#1038 (comment)>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/AICWJGSXBSUSUAORVULNSQD3BVBOZAVCNFSM6AAAAAB5SC73WGVHI2DSMVQWIX3LMV43OSLTON2WKQ3PNVWWK3TUHMZDSMZTG44DAMRTHA> . You are receiving this because you authored the thread.Message ID: ***@***.***>

[lance6716]

--- FAIL: TestSyncerSuite (18.99s)
    --- FAIL: TestSyncerSuite/TestFloatWithTrailingZeros (0.03s)
        suite.go:87: test panicked: interface conversion: interface {} is string, not []uint8
            goroutine 52 [running]:
            runtime/debug.Stack()
            	/home/runner/go/pkg/mod/golang.org/[email protected]/src/runtime/debug/stack.go:26 +0x67
            github.com/stretchr/testify/suite.failOnPanic(0xc0001901c0, {0xee6a00, 0xc0000a5050})
            	/home/runner/go/pkg/mod/github.com/stretchr/[email protected]/suite/suite.go:87 +0x4e
            github.com/stretchr/testify/suite.Run.func1.1()
            	/home/runner/go/pkg/mod/github.com/stretchr/[email protected]/suite/suite.go:183 +0x359
            panic({0xee6a00?, 0xc0000a5050?})
            	/home/runner/go/pkg/mod/golang.org/[email protected]/src/runtime/panic.go:792 +0x132
            github.com/go-mysql-org/go-mysql/replication.(*testSyncerSuite).testFloatWithTrailingZerosCase(0xc000316000, 0x1)
            	/home/runner/work/go-mysql/go-mysql/replication/replication_test.go:531 +0x7af
            github.com/go-mysql-org/go-mysql/replication.(*testSyncerSuite).TestFloatWithTrailingZeros(0xc000316000)
            	/home/runner/work/go-mysql/go-mysql/replication/replication_test.go:484 +0xb2
            reflect.Value.call({0xc000318f80?, 0xc00005ef30?, 0x13?}, {0xf7f62f, 0x4}, {0xc00011fea8, 0x1, 0x1?})
            	/home/runner/go/pkg/mod/golang.org/[email protected]/src/reflect/value.go:584 +0xd4e
            reflect.Value.Call({0xc000318f80?, 0xc00005ef30?, 0x604520?}, {0xc000185ea8, 0x1, 0x1})
            	/home/runner/go/pkg/mod/golang.org/[email protected]/src/reflect/value.go:368 +0xb6
            github.com/stretchr/testify/suite.Run.func1(0xc0001901c0)
            	/home/runner/go/pkg/mod/github.com/stretchr/[email protected]/suite/suite.go:1[97](https://github.com/go-mysql-org/go-mysql/actions/runs/15448405868/job/43507909759?pr=1038#step:6:98) +0x6ee
            testing.tRunner(0xc0001901c0, 0xc00016c870)
            	/home/runner/go/pkg/mod/golang.org/[email protected]/src/testing/testing.go:1792 +0x226
            created by testing.(*T).Run in goroutine 22
            	/home/runner/go/pkg/mod/golang.org/[email protected]/src/testing/testing.go:1851 +0x8f3
FAIL

[chenhuiyeh]

I decided to pull the unit tests out specifically for this feature/fix