Error in mfunc: attempt to apply non-function

[daattali]

I have a shiny server pro v1.5.10.990 installed on an ubuntu machine.

A few weeks ago all the shiny apps hosted on the server started returning a 500 error.

The error logs for any app that I attempted to visit all had the same short contents:

Warning: Error in mfunc: attempt to apply non-function
  1: runApp

@wch told to me on Twitter that {bslib} has a function called "mfunc" so I might want to look there on my troubleshooting journey. It turns out that when I have {bslib} v0.4.0 installed, the above error happens. When I install v0.3.0, my shiny server works fine.

[cpsievert]

Thanks for the report! Can you repro the issue with a "hello world" app (e.g., shiny::runExample("01_hello"))?

[daattali]

I can repro the issue with an app.R file that has shiny::shinyApp("test", function(input,output){})

[daattali]

And similarly, with an Rmd file that has nothing other than frontend YAML

[cpsievert]

And what R version is this running on?

[daattali]

3.6.1

[cpsievert]

I can repro this issue (outside of SSP/SSO) with {memoise} 1.1.0 (on R 3.5.3) by running this app. Upgrading to the latest CRAN release (2.0.1) fixes it

[daattali]

Can confirm being on {bslib} 0.4.0 with memoise 2.0.0 works

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