fix: EXPOSED-983 Support reading JSONB columns outside transaction by using ResultRow.database instead of current transaction when checking dialect

[bystam]

Description

A recent change in how JSONB is treated in SQLite has caused an unexpected behavior when reading JSONB columns outside the transaction.

For us it's a common pattern to return entities from a transaction and then perform read-only operations on them (such as writing to some kind of JSON endpoint output), and when bumping to 1.0.0 we started seeing crashes, because the change linked upstairs pokes at currentDialect when parsing the json column.

By checking the stack trace, I noticed that the specific codepath that crashes has access to the database use to retrieve the ResultRow, and therefore we can avoid the crash by reading the dialect from there instead of from the thread-local.

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Type of Change

Please mark the relevant options with an "X":

• Bug fix
• New feature
• Documentation update

Updates/remove existing public API methods:

• Is breaking change

Affected databases:
Note: I'm not sure if this change can be considered to affect any of these databases specifically

• MariaDB
• Mysql5
• Mysql8
• Oracle
• Postgres
• SqlServer
• H2
• SQLite

Checklist

• Unit tests are in place
• The build is green (including the Detekt check)
• All public methods affected by my PR has up to date API docs
• Documentation for my change is up to date

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Related Issues

https://youtrack.jetbrains.com/issue/EXPOSED-983/JSONB-columns-cannot-be-read-outside-of-transaction

[bystam]

From what I could tell, currentDialect is SQLiteDialect was double-checked both here and inside needsBinaryFormatCast, but only one of them should be required?

At least from what I could tell from the callers of both functions

[bystam]

This is the fix that actually avoids the crash - by using database?.dialect and avoiding checking the current transaction

[bystam]

I couldn't find a way to inject the "current database" as easily from from 2 other places where isJsonBColumnForCasting is called:

• Alias.kt
• Table.kt

Maybe it's OK to have them simply use the thread-local?

[bystam]

This last line crashes without the fix upstairs