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Currently, when the P2J Progress parser encounters unexpected tokens during runtime query conversion due to invalid input, it simply dumps error messages and stack traces to stderr, and we pick these up in the server log.

Greg mentioned there is a way to configure the parser to make these errors throw an exception. This would be preferable, since it would allow us to detect a fatal error much earlier during dynamic query conversion. This would prevent unnecessary work, and more importantly, any unreliable behavior which results from attempting to continue when a fatal parsing error has occurred.

Please investigate how to configure the parser to enable this behavior. This should be set only for runtime parsing. For static conversion, we want the parser to continue working on the next file, rather than aborting a conversion batch job.

See setConsumeError() and reportError() in progress.g.

Code review 0324b:

Looks fine. If you have tested successfully locally, please commit and distribute. There is no test for this in the standard regression test environment.

• must be a quoted constant or an unabbreviated,.., when the broken token is a (possible) identifier
• ** Unable to understand after + syntax on next line, when the invalid token is a keyword

b-2:FIND-FIRST("WHERE tmp.af > 0").

P4GL:   tmp af must be a quoted constant or an unabbreviated, unambiguous
       buffer/field reference for buffers known to query or FIND. (7328)

P2J:   Could not parse the 'WHERE tmp.af > 0' predicate for query find_FIRST_SHARE. (-1)
exc:   NoViableAltException: unexpected token: tmp.af
       "NoViableAlt" token: ["tmp.af",<6>,line=1,col=23]

b-2:FIND-FIRST("WHERE And tmp.af > 0").

P4GL:      ** Unable to understand after -- "WHERE". (247)
       FIND METHOD syntax is: [WHERE []] [USE-INDEX ]. (10086)

hQuery:QUERY-PREPARE("FOR EACH book WHERE tmp.uu AND isbn = '101'").

P4GL:  tmp uu must be a quoted constant or an unabbreviated, unambiguous
          buffer/field reference for buffers known to query . (7328)

hQuery:QUERY-PREPARE("FOR EACH book WHERE AND isbn = '101'").

P4GL:      ** Unable to understand after -- "EACH book WHERE". (247)
       PREPARE syntax is: {FOR | PRESELECT} EACH  OF.. WHERE ... etc". (7324)

P2J:   Could not parse the 'FOR EACH book WHERE AND isbn = '101'' predicate for query . (-1)
exc:   NoViableAltException: line 1:44: unexpected token: AND
       "NoViableAlt" token: ["AND",<471>,line=1,col=44]

It seems like we have enough information from the parser and the context of what we are doing at the time to quickly add the appropriate syntax message (line 3), but matching the other behavior looks like it could be a bit tricky, and probably is of relatively low value for most applications. Yes, we'll want to fix this ultimately, but there are higher priority issues to work on right now.

Please go ahead with adding the syntax message and we'll put the rest on hold for now.

Code review 0415b:

Looks good, but needs to be merged up to latest version. Assuming you've tested locally, please merge, commit, and distribute.

Is there anything left to do on this issue at this point, or can it be closed?

Code review 0519a:

I'm glad you made this change, I was going to ask for something like it. After you made the error messages more like Progress in the previous update, we actually lost information, because our older message was more informative than Progress. Nice to have it back.

The refactoring of the logging looks good, with one caveat: note that INFO is the default level for all loggers, so if you don't want the stack traces in the log by default (which I think is appropriate -- one typically wants to see this detail only when debugging the problem revealed by the more general error messages), you should change the logging level at line 1605 to CONFIG or lower. Assuming you manually test this change successfully, regression testing is not necessary. I would recommend making that one level change and then you can check it in.