Bugfix/issue 2044 ternary op result for mismatched types; fixes #2044

[bob-carpenter]

Submisison Checklist

• Run unit tests: ./runTests.py src/test/unit
• Run cpplint: make cpplint
• Declare copyright holder and open-source license: see below

Summary

Fix promotion in conditional operator in Stan language to match context.

Intended Effect

Fixes issue #2044 in which a generated var was being cast to double. Also reduces overpromotion in general for more efficiency when both arguments are scalar.

How to Verify

Unit tests plus compilability of test-models/good/validate_conditional_op_good.stan (this was broken in 2.11 tests)

Side Effects

No.

Documentation

n/a

Reviewer Suggestions

Anyone.

Copyright and Licensing

Please list the copyright holder for the work you are submitting (this will be you or your assignee, such as a university or company):

Mitzi Morris
Columbia University

By submitting this pull request, the copyright holder is agreeing to license the submitted work under the following licenses:

• Code: BSD 3-clause (https://opensource.org/licenses/BSD-3-Clause)
• Documentation: CC-BY 4.0 (https://creativecommons.org/licenses/by/4.0/)

[syclik]

Jenkins, retest this please.

[syclik]

I verified that the unit test does compile using CmdStan!

[syclik]

Thanks, Bob. I looked through the code and it looks reasonable.

[bob-carpenter]

Great. The integration tests pass with the fixes Mitzi put in. We did the final review on my machine and I pushed some refactoring and doc and the revised model. Someone else should code review it, but it looked OK to both of us.

[syclik]

I took a look. If I stare at it long enough, I think I can understand it. Looks good. I'll merge once it passes tests on travis.