geom_sina(): stat_sina() fails in locales

[derekbeaton]

geom_sina() is does not provide output images and stops on one of my machines (Ubuntu 16.04.5 LTS; sessionInfo attached below). All geom_sina() calls generate the same warning message:

Warning message:
Computation failed in stat_sina():
Please use to_lower_ascii(), which works fine in all locales.

All generated images have the base graphics, but none of the individual points that would be generated through geom_sina(). I've taken a look at the traceback() and in other issues, but I'm not sure what that warning message means (and why exactly the computation stops, and the images are effectively empty).

I see the following problem with real data and illustrative data. An illustrative example is below (generated in a similar way from a prior issue: #48).

df <- data.frame(g=c("A","B"),v=rnorm(100))
ggplot(df, aes(x=g,y=v)) + geom_point() ##works
ggplot(df, aes(x=g,y=v)) + geom_violin() ##works
ggplot(df, aes(x=g,y=v)) + geom_sina() ##does not work

sessionInfo():
R version 3.4.3 (2017-11-30)
Platform: x86_64-pc-linux-gnu (64-bit)
Running under: Ubuntu 16.04.5 LTS

Matrix products: default
BLAS: /usr/lib/libblas/libblas.so.3.6.0
LAPACK: /usr/lib/lapack/liblapack.so.3.6.0

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

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

other attached packages:
[1] reshape2_1.4.3 ggpubr_0.2 magrittr_1.5 ggforce_0.2.1 kableExtra_0.9.0 knitr_1.20
[7] plyr_1.8.4 TInPosition_0.13.6 InPosition_0.12.7 TExPosition_2.6.10 ExPosition_2.8.19 prettyGraphs_2.1.5
[13] ours_0.0.0.9000 GSVD_0.2.0 ggplot2_3.1.0

loaded via a namespace (and not attached):
[1] tidyselect_0.2.5 purrr_0.3.0 colorspace_1.3-2 htmltools_0.3.6 viridisLite_0.3.0 yaml_2.1.19
[7] rlang_0.3.1 pillar_1.3.1 glue_1.3.0 withr_2.1.2 tweenr_1.0.1 RColorBrewer_1.1-2
[13] bindrcpp_0.2.2 bindr_0.1.1 stringr_1.4.0 munsell_0.5.0 gtable_0.2.0 rvest_0.3.2
[19] evaluate_0.10.1 labeling_0.3 Rcpp_1.0.0 readr_1.1.1 scales_1.0.0 backports_1.1.2
[25] farver_1.1.0 hms_0.4.2 digest_0.6.18 stringi_1.3.1 dplyr_0.7.8 polyclip_1.9-1
[31] grid_3.4.3 rprojroot_1.3-2 tools_3.4.3 lazyeval_0.2.1 tibble_2.0.1 crayon_1.3.4
[37] pkgconfig_2.0.2 pheatmap_1.0.10 MASS_7.3-45 xml2_1.2.0 assertthat_0.2.0 rmarkdown_1.10
[43] httr_1.3.1 rstudioapi_0.7 R6_2.3.0 compiler_3.4.3

[derekbeaton]

Follow up: I've attached the images from the above example.

[derekbeaton]

I just noticed this is a duplicate of #134