Cannot reprex `traceback()`
jooyoungseo opened this issue · comments
This is a side note while working on rstudio/tensorflow#494.
reprex::reprex() doesn't work as expected against traceback().
Reprex
- Copy and paste the following code in R console:
stop("test")
traceback()- Run
reprex::reprex().
Expected Results
stop("test")
#> Error: test
traceback()
#> 1: stop("test") Current Results
stop("test")
#> Error in eval(expr, envir, enclos): test
traceback()
#> No traceback availableCreated on 2022-01-04 by the reprex package (v2.0.1)
Session info
sessioninfo::session_info()
#> - Session info ---------------------------------------------------------------
#> setting value
#> version R version 4.1.2 (2021-11-01)
#> os Windows 10 x64 (build 19044)
#> system x86_64, mingw32
#> ui RTerm
#> language (EN)
#> collate English_United States.1252
#> ctype English_United States.1252
#> tz America/Chicago
#> date 2022-01-04
#> pandoc 2.16.2 @ C:/PROGRA~3/CHOCOL~1/bin/ (via rmarkdown)
#>
#> - Packages -------------------------------------------------------------------
#> package * version date (UTC) lib source
#> cli 3.1.0 2021-10-27 [1] CRAN (R 4.1.2)
#> crayon 1.4.2 2021-10-29 [1] CRAN (R 4.1.2)
#> digest 0.6.29 2021-12-01 [1] CRAN (R 4.1.2)
#> ellipsis 0.3.2 2021-04-29 [1] CRAN (R 4.1.2)
#> evaluate 0.14 2019-05-28 [1] CRAN (R 4.1.2)
#> fansi 0.5.0 2021-05-25 [1] CRAN (R 4.1.2)
#> fastmap 1.1.0 2021-01-25 [1] CRAN (R 4.1.2)
#> fs 1.5.2 2021-12-08 [1] CRAN (R 4.1.2)
#> glue 1.6.0 2021-12-17 [1] CRAN (R 4.1.2)
#> highr 0.9 2021-04-16 [1] CRAN (R 4.1.2)
#> htmltools 0.5.2 2021-08-25 [1] CRAN (R 4.1.2)
#> knitr 1.37 2021-12-16 [1] CRAN (R 4.1.2)
#> lifecycle 1.0.1 2021-09-24 [1] CRAN (R 4.1.2)
#> magrittr 2.0.1 2020-11-17 [1] CRAN (R 4.1.2)
#> pillar 1.6.4 2021-10-18 [1] CRAN (R 4.1.2)
#> pkgconfig 2.0.3 2019-09-22 [1] CRAN (R 4.1.2)
#> purrr 0.3.4 2020-04-17 [1] CRAN (R 4.1.2)
#> R.cache 0.15.0 2021-04-30 [1] CRAN (R 4.1.2)
#> R.methodsS3 1.8.1 2020-08-26 [1] CRAN (R 4.1.1)
#> R.oo 1.24.0 2020-08-26 [1] CRAN (R 4.1.1)
#> R.utils 2.11.0 2021-09-26 [1] CRAN (R 4.1.2)
#> reprex 2.0.1 2021-08-05 [1] CRAN (R 4.1.2)
#> rlang 0.4.12 2021-10-18 [1] CRAN (R 4.1.2)
#> rmarkdown 2.11 2021-09-14 [1] CRAN (R 4.1.2)
#> sessioninfo 1.2.2 2021-12-06 [1] CRAN (R 4.1.2)
#> stringi 1.7.6 2021-11-29 [1] CRAN (R 4.1.2)
#> stringr 1.4.0 2019-02-10 [1] CRAN (R 4.1.2)
#> styler 1.6.2.9000 2021-12-29 [1] Github (r-lib/styler@f672907)
#> tibble 3.1.6 2021-11-07 [1] CRAN (R 4.1.2)
#> utf8 1.2.2 2021-07-24 [1] CRAN (R 4.1.2)
#> vctrs 0.3.8 2021-04-29 [1] CRAN (R 4.1.2)
#> withr 2.4.3 2021-11-30 [1] CRAN (R 4.1.2)
#> xfun 0.29 2021-12-14 [1] CRAN (R 4.1.2)
#> yaml 2.2.1 2020-02-01 [1] CRAN (R 4.1.1)
#>
#> [1] C:/Program Files/R/R-4.1.2/library
#>
#> ------------------------------------------------------------------------------
This is a limitation that comes from knitr / rmarkdown and therefore reprex just inherits it.
We can remove reprex from the equation and demonstrate this.
If you save the following as foo.Rmd:
---
output: github_document
---
`traceback()` doesn't work in R Markdown.
```{r error = TRUE}
stop("test")
traceback()
```
and then call rmarkdown::render("foo.Rmd"), the rendered result is:
traceback() doesn’t work in R Markdown.
stop("test")## Error in eval(expr, envir, enclos): test
traceback()## No traceback available
Now, it is also true that it is possible to promote base errors to rlang errors and thereby gain access to rlang's richer machinery for inspecting the back trace. But last time I checked, it was not clear exactly what reprex should do to simultaneously do this promotion and display errors in Rmd. In any case, the matter of optimizing how reprex uses these rlang features is being tracked in #377.