persistent-mysql: treat tinyint as SqlOther "tinyint", not SqlBool

[fumieval]

I noticed that our application reports schema mismatch after upgrading to MySQL 8.0, even if I change the column type to SqlOther "tinyint" (removing the width). I realised that the recent versions of persistent-mysql parses tinyint as SqlBool, but it doesn't work in our usecase, where some tinyint columns represent non-Boolean values.

After this change, I confirmed that our application works both on MySQL 5.7 and MySQL 8.0, but I'm not quite confident that this change is in the right direction. What are your thoughts?

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[paul-rouse]

This looks reasonable to me. It relies on the exception documented in the MySQL 8.0.19 release notes concerning the deprecation of the width specification for integer data types - it does appear that there is an intention to retain tinyint(1) as a special case.

There are a couple of things you could do to tidy up the code:

• the comment on parseColumnType needs to be updated to refer to this exception to the general deprecation of integer width specification, and the comment in showSqlType specifically about the Bool case can be removed.
• I can't see any reason for the second condition (the one with stripPrefix), since removing the tinyint alternative from the condition will make anything other than tinyint(1) fall through to the catch-all case of parseColumnType at the bottom. Doesn't that do what you want?

[fumieval]

Thank you for a comment. Given that they intend to keep tinyint(1) as an exception, this seems much safer than I originally anticipated. I reflected your suggestions in the code

[paul-rouse]

@parsonsmatt can you see any issues with this? Just to make sure we don't break anything!

[parsonsmatt]

Code looks fine to me. I'm curious if you could write a test to demonstrate the behavior you're looking for?

[fumieval]

I added a unit test that tests this behaviour. Would that suffice?

[parsonsmatt]

I think this file wasn't checked in

[parsonsmatt]

I'd prefer to see that persistent has the right behavior when interacting with a sql=tinyint column. Testing the parsing logic seems less valuable than that the actual interaction with the database layer works appropriately.

[parsonsmatt]

Fantastic, thanks! I'll go ahead and release this.