JTASK-863: fix bug in Option[T].Scan #2
Merged
Conversation
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
nojima
changed the title
pddg
requested changes
Nov 22, 2023
options.go
Outdated
Comment on lines
178
to
192
| // Convert between string and []byte | ||
| dstType := reflect.TypeOf(dst.value) | ||
| srcType := reflect.TypeOf(src) | ||
| if isByteSlice(srcType) && dstType.Kind() == reflect.String { | ||
| src = string(src.([]byte)) | ||
| *dst = New(src.(T)) | ||
| return nil | ||
| } | ||
| if srcType.Kind() == reflect.String && isByteSlice(dstType) { | ||
| src = []byte(src.(string)) | ||
| *dst = New(src.(T)) | ||
| return nil | ||
| } | ||
|
|
||
| return fmt.Errorf("Option[%T].Scan: failed to convert value %#v to type %T", dst.value, src, dst.value) |
There was a problem hiding this comment.
It seems that the dst and src type mismatch problem is not limited to strings.
https://zenn.dev/methane/articles/2023-go-mysql-parse-numbers
If we wanted full SQL Driver support with Option type, the flow would be something like this
- if
srcisnil,dstbecomesNone - if
dsttype implements a Scanner interface, use it - if
dsttype is a primitive (or its defined type), use a huge switch statement to achieve the conversion, just as the sql package does. https://cs.opensource.google/go/go/+/master:src/database/sql/convert.go;l=211?q=convertAssign&ss=go%2Fgo
Or, we may be able to use sql.Null[T] after releasing go 1.22.
golang/go#60370
|
For now, I decided to copy and use the standard Go library implementation. |
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
Add this suggestion to a batch that can be applied as a single commit.
This suggestion is invalid because no changes were made to the code.
Suggestions cannot be applied while the pull request is closed.
Suggestions cannot be applied while viewing a subset of changes.
Only one suggestion per line can be applied in a batch.
Add this suggestion to a batch that can be applied as a single commit.
Applying suggestions on deleted lines is not supported.
You must change the existing code in this line in order to create a valid suggestion.
Outdated suggestions cannot be applied.
This suggestion has been applied or marked resolved.
Suggestions cannot be applied from pending reviews.
Suggestions cannot be applied on multi-line comments.
Suggestions cannot be applied while the pull request is queued to merge.
Suggestion cannot be applied right now. Please check back later.
No description provided.