Can't print from transformed data

Summary:

print() statements executed from the transformed data block are not displayed back to the user.

Description:

print() statements executed in transformed data should be shown to the user. This was the old behavior (not sure when it changed, but I think around 2.19). See the 'print frequency' section here: https://mc-stan.org/docs/2_24/reference-manual/print-statements-section.html for confirmation that these print statements should show up.

This is particularly useful from rstan to, e.g., keep track of making sure the correct version of the source code is running.

Reproducible Steps:

See source code in the attached file:
stanprint.txt

Current Output:

samples <- sampling(test_model, data = list(n = 3), chains = 1, iter = 2, open_progress = T, show_messages = T)

SAMPLING FOR MODEL '67e266178e2a1aef57a3b6ce7f76543e' NOW (CHAIN 1).
Chain 1: alpha= 1.54289 beta = -0.313112

Chain 1: alpha= 1.54289 beta = -0.313112

Expected Output:

samples <- sampling(test_model, data = list(n = 3), chains = 1, iter = 2, open_progress = T, show_messages = T)
Chain 1: n= 3
SAMPLING FOR MODEL '67e266178e2a1aef57a3b6ce7f76543e' NOW (CHAIN 1).
Chain 1: alpha= 1.54289 beta = -0.313112

Chain 1: alpha= 1.54289 beta = -0.313112

RStan Version:

2.21.2

R Version:

R version 3.6.2 (2019-12-12)

Operating System:

OS X 10.15.5

Start with the attached stanprint.txt reproduction and the referenced Stan print-frequency documentation, then reproduce the missing transformed-data output with RStan 2.21.2. Trace how sampling output is captured and displayed; done means print() output from transformed data appears before the sampling message as shown in the expected output.