Generator produces an invalid enum with an underscore "_" as the name

[nyoungac]

Using the 3.14.1 code generator with Java on a MySQL database with an enum field defined as:

  `t_offset_o` enum('-','+') NOT NULL DEFAULT '+',

OR

  `ref` enum('', <...>) NOT NULL DEFAULT '',

produce an invalid underscore "_" enum:

_(""),

expected: Have some placeholder or random name.

[lukaseder]

Thanks for your report. As a workaround, you can always implement a generator strategy to assign different identifiers to your enums: https://www.jooq.org/doc/latest/manual/code-generation/codegen-generatorstrategy/

[lukaseder]

This seems to be an oversight in the fix for #4703.

[lukaseder]

Hmm, no. Unfortunately, generator strategies aren't involved in generating the identifiers for enum literals. That might be another issue: #10881

Your examples show an interesting case. While it would be possible to disambiguate the _ characters individually, if you had created an enum like this, we'd get yet another issue where disambiguated identifiers create a conflict, because they're both the same:

enum ('', '-')

I don't want to rush fixing this. It seems that name disambiguation could use some more thorough thought...

[lukaseder]

Another workaround is to use a CHECK (t_offset_o IN ('-', '+')) constraint, and make it CHAR(1) instead of ENUM

[berndwaibel]

Same Problem here: MySQL, Enum Type:
enum('store','single','multiple','sold','')
The "" string does produce an underscore.

This is a very bad problem, as this is no more supported in JDK > 9.
So the created code (created by Jooq 3.14.4) will not compile if the JDK Level is 9 or above

Warning in JDK 8:
error: as of release 9, '_' is a keyword, and may not be used as an identifier _(""),

As this is a "does not compile" error, is it possible to put the priority a little bit higher than medium?

[lukaseder]

Starting from jOOQ 3.16, such problems can be worked around using a GeneratorStrategy configuration: #10881

We should obviously never generate _ enum literals, but at least there will be a workaround until this is fixed.

[lukaseder]

I'm fixing this particular issue here, where enum literals can be produced by the name _. For now, they just generate __. It seems that the fix from #4703 wasn't applied to enum literals.

There's still more name mangling to be done, but it might be more edge-casey than this one (?): #12732

Again, at least with 3.16, the GeneratorStrategy now supports overriding the default behaviour for enum literals as well via #10881.

[lukaseder]

Fixed in jOOQ 3.16. I won't backport this fix, because it could break existing generated code elsewhere.