ambition: hard-coded MySQL syntax in WhereProcessor methods

Here's a patch that adds a quote_column_name facade for the ActiveRecord connection to Processor, which is then used in WhereProcessor#translate.

The patch has no tests, because I can't figure out a way to test without using a live ActiveRecord connnection.

I will gladly add some tests, if someone can give me a clue on how to mock or stub or prestidigitate an AR connection, so that I can access the adapter-specific quoting methods.

Regarding REGEXP and SQL standards, I dunno. I haven't been using postgres long, and I have to look everything up anyway. Speaking of which, the PostgreSQL manual has a table showing regex operators:

http://www.postgresql.org/docs/8...

It should be easy to add a clumsy helper method that picks a regex operator based on the AR::Base.connection adapter, but that seems ugly.

I think having database-specific translators maybe the only way. Since that requires some architecture re-thinking, I may take that on later tonight sometime. Suck.

I added the column_name thing. I need to improve to_sql generation -- right now it's not matching the actual SQL called. Note to self.

http://projects.require.errthebl...

Re: database-specific translators for regexp

How bad of an idea is this?

Monkeypatch each ActiveRecord adapter with regexp-producing methods, then call them in WhereProcessor#process_match3 using:

ActiveRecord::Base.connection.regexp(value)

or a suitable helper method.

I'm uploading a meaty patch (with tests!) that implements the idea in my last comment. I.e., it monkeypatches the Abstract, MySQL, and PostgreSQL adapters with a method named ambition_regexp. It also adds a method named adapter_regexp to Processor and slightly smartens the rescue clauses in the quoting methods. The results are not as ugly as I had feared.

In where_test.rb, I added contexts for MySQL, PostgreSQL, and an adapter that doesn't get monkeypatched (so I can test the Abstract adapter). It turns out that you can fake a new PostgreSQL connection by passing it strings for args, and you can fake a MySQL connection by overriding its connect method and passing strings for args. This appears to be sufficient to test the helper methods in these classes, namely the quoting.

Do you have AIM or hang out on IRC? I'm doing some refactoring today and want to talk to you about this patch / concept.

I usually don't do the chatty things, but I can on weekdays. On weekends, my real boss requests that I keep computer work to a minimum.