Failure with dev evaluate

[hadley]

When I render features.Rmd with dev evaluate I see:

Warning message:
In file("", "w+b") :
  cannot open file '/tmp/RtmpZpUGvo/Rf3a0a4169aeaa': No such file or directory

This error is coming from evaluate but appears to be because word-predictor is deleting the temporary directory. If I set ve = 1 and patch dm() to use stderr() I see:

Copying file: test.txt to /tmp/RtmpZpUGvo ✔
Copying file: validate.txt to /tmp/RtmpZpUGvo ✔
Copying file: validate-clean.txt to /tmp/RtmpZpUGvo ✔
Copying file: test-clean.txt to /tmp/RtmpZpUGvo ✔
Reading '/tmp/RtmpZpUGvo/test-clean.txt' ✔
Reading '/tmp/RtmpZpUGvo/test.txt' ✔
Reading '/tmp/RtmpZpUGvo/validate-clean.txt' ✔
Reading '/tmp/RtmpZpUGvo/validate.txt' ✔
Removing the folder /tmp/RtmpZpUGvo ✔

And obviously deleting the temporary directory is a bad idea.

I plan on submitting evaluate to CRAN on Sept 16, so you'll have a couple of weeks after that to fix the problem.