[Bug]: Multiple re-renders of the same article produces error

[averissimo]

What happened?

When rendering an article multiple times across sessions it sometimes leads to the error below.

This happens as:

• knitr_utils chunk recognizes the environment as being a test environment
• Then triggers the save of an RDS file on testenv chunk
• This requires an environment variable that doesn't exist
• it ends up trying to write to the root directory.

processing file: lbt02.qmd
  |........................                               |  44% [save testenv]
Quitting from lines 2-10 [save testenv] (lbt02.qmd)
Error in `gzfile()`:
! cannot open the connection
Backtrace:
 1. base::saveRDS(tenv, filepath)
 2. base::gzfile(file, mode)
                                                                                                         
Execution halted

@kartikeyakirar also reproduced this error

It is corrected when:

diff --git a/book/tables/lab-results/lbt02.qmd b/book/tables/lab-results/lbt02.qmd
index a0f0e47d..1f02fca6 100644
--- a/book/tables/lab-results/lbt02.qmd
+++ b/book/tables/lab-results/lbt02.qmd
@@ -62,7 +62,7 @@ result
 
 ## `teal` App
 
-```{r teal, message=FALSE, opts.label='skip_if_testing'}
+```{r teal, message=FALSE, opts.label='skip_if_testing', cache=FALSE}
 #| screenshot.opts = list(delay = 8)
 
 library(scda)

Relevant log output

R version 4.3.2 (2023-10-31)
Platform: x86_64-pc-linux-gnu (64-bit)
Running under: Ubuntu 23.10

Matrix products: default
BLAS: /usr/lib/x86_64-linux-gnu/blas/libblas.so.3.11.0
LAPACK: /usr/lib/x86_64-linux-gnu/lapack/liblapack.so.3.11.0

locale:
[1] LC_CTYPE=en_US.UTF-8 LC_NUMERIC=C LC_TIME=en_IE.UTF-8 LC_COLLATE=en_US.UTF-8 LC_MONETARY=en_IE.UTF-8 LC_MESSAGES=en_US.UTF-8 LC_PAPER=en_IE.UTF-8
[8] LC_NAME=C LC_ADDRESS=C LC_TELEPHONE=C LC_MEASUREMENT=en_IE.UTF-8 LC_IDENTIFICATION=C

time zone: Europe/Berlin
tzcode source: system (glibc)

attached base packages:
[1] stats graphics grDevices datasets utils methods base

loaded via a namespace (and not attached):
[1] utf8_1.2.4 R6_2.5.1 tidyselect_1.2.0 magrittr_2.0.3 glue_1.6.2 tibble_3.2.1 pkgconfig_2.0.3 dplyr_1.1.4 generics_0.1.3
[10] lifecycle_1.0.4 cli_3.6.1 fansi_1.0.5 vctrs_0.6.5 rsconnect_1.1.1 testthat_3.2.1 withr_2.5.2 renv_1.0.3 compiler_4.3.2
[19] rstudioapi_0.15.0 tools_4.3.2 brio_1.1.3 pillar_1.9.0 yaml_2.3.7 BiocManager_1.30.22 rlang_1.1.2

Code of Conduct

• I agree to follow this project's Code of Conduct.

Contribution Guidelines

• I agree to follow this project's Contribution Guidelines.

Security Policy

• I agree to follow this project's Security Policy.