PCRE pattern compilation error with sv_url

[bhogan-mitre]

I'm getting an error in some environments with the sv_url function. Is it possible there is an unstated system requirement? I am unsure where the error may be coming from otherwise.

  PCRE pattern compilation error
	'invalid UTF-8 string'

> example("sv_url")

sv_url> ## Only run examples in interactive R sessions
sv_url> if (interactive()) {
sv_url+ 
sv_url+ library(shiny)
sv_url+ library(shinyvalidate)
sv_url+ 
sv_url+ ui <- fluidPage(
sv_url+   textInput("url", "URL")
sv_url+ )
sv_url+ 
sv_url+ server <- function(input, output, session) {
sv_url+   
sv_url+   # Validation rules are set in the server, start by
sv_url+   # making a new instance of an `InputValidator()`
sv_url+   iv <- InputValidator$new()
sv_url+ 
sv_url+   # Basic usage: `sv_url()` works well with its
sv_url+   # defaults; a message will be displayed if the
sv_url+   # validation of `input$address` fails
sv_url+   iv$add_rule("url", sv_url())
sv_url+ 
sv_url+   # Finally, `enable()` the validation rules
sv_url+   iv$enable()
sv_url+ }
sv_url+ 
sv_url+ shinyApp(ui, server)
sv_url+ 
sv_url+ }

Listening on http://127.0.0.1:6179
Warning in grepl("^(?:(?:http(?:s)?|ftp)://)(?:\\S+(?::(?:\\S)*)?@)?(?:(?:[a-z0-9¡-\uffff](?:-)*)*(?:[a-z0-9¡-\uffff])+)(?:\\.(?:[a-z0-9¡-\uffff](?:-)*)*(?:[a-z0-9¡-\uffff])+)*(?:\\.(?:[a-z0-9¡-\uffff]){2,})(?::(?:\\d){2,5})?(?:/(?:\\S)*)?$",  :
  PCRE pattern compilation error
	'invalid UTF-8 string'
	at '](?:-)*)*(?:[a-z0-9¡-])+)(?:\.(?:[a-z0-9¡-](?:-)*)*(?:[a-z0-9¡-])+)*(?:\.(?:[a-z0-9¡-]){2,})(?::(?:\d){2,5})?(?:/(?:\S)*)?$'
Warning: Error in grepl: invalid regular expression '^(?:(?:http(?:s)?|ftp)://)(?:\S+(?::(?:\S)*)?@)?(?:(?:[a-z0-9¡-](?:-)*)*(?:[a-z0-9¡-])+)(?:\.(?:[a-z0-9¡-](?:-)*)*(?:[a-z0-9¡-])+)*(?:\.(?:[a-z0-9¡-]){2,})(?::(?:\d){2,5})?(?:/(?:\S)*)?$'
  71: grepl
  70: rule_fn
  69: <Anonymous>
  67: rule$rule
  53: <Anonymous>
  52: mapply
  51: self$`_validate_impl`
  50: self$validate
  49: ::
shiny
observe
  48: <observer>
   5: runApp
   4: print.shiny.appobj
   2: source
   1: example

Here is the session info:

R version 3.6.0 (2019-04-26)
Platform: x86_64-redhat-linux-gnu (64-bit)
Running under: Red Hat Enterprise Linux

Matrix products: default
BLAS/LAPACK: /usr/lib64/R/lib/libRblas.so

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

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

other attached packages:
[1] shinyvalidate_0.1.2 shiny_1.7.1        

loaded via a namespace (and not attached):
 [1] Rcpp_1.0.8       crayon_1.5.0     digest_0.6.29    later_1.3.0      mime_0.12       
 [6] R6_2.5.1         jsonlite_1.8.0   lifecycle_1.0.1  xtable_1.8-4     magrittr_2.0.2  
[11] cachem_1.0.6     rlang_1.0.4      cli_3.3.0        rstudioapi_0.13  promises_1.2.0.1
[16] jquerylib_0.1.4  bslib_0.3.1      ellipsis_0.3.2   tools_3.6.0      rsconnect_0.8.26
[21] httpuv_1.6.5     fastmap_1.1.0    compiler_3.6.0   htmltools_0.5.2  sass_0.4.0 

Note that I have run this successfully in R 3.6.0 on my Mac, so I don't think it is as simple as an R version thing. Please let me know if you have any suggestions. Thanks.

[bhogan-mitre]

This note on the man page for grepl seems relevant:

 Caseless matching with ‘perl = TRUE’ for non-ASCII characters depends on the PCRE library being compiled with ‘Unicode property support’: an external library might not be.

As do these configuration checks:

> extSoftVersion()
                          zlib                          bzlib
                       "1.2.7"           "1.0.6, 6-Sept-2010"
                            xz                           PCRE
                       "5.2.2"              "8.32 2012-11-30"
                           ICU                            TRE
                        "50.2"              "TRE 0.8.0 (BSD)"
                         iconv                       readline
                  "glibc 2.17"                          "6.2"
                          BLAS
"/usr/lib64/R/lib/libRblas.so"
> pcre_config()
             UTF-8 Unicode properties                JIT              stack
              TRUE               TRUE               TRUE               TRUE

I think the relevant piece here is that if R is linked with an older PCRE(1) such as the 8.32 on this instance, sv_url isn't going to work.