glue_sql : quote integer if NA in the column

[philibe]

It's a little the next of #115 : When I have an Integer with NA in same column, I get the integer with quote.

However it's casted by my SGBDR.
When I replace .con = DBI::ANSI() by my SQL Server connection I have the same bug.

library(glue)

glue_sql(
  "{Col_int}",
  Col_int = data.frame(
    Col_int = c(1L, NA_integer_),
    stringsAsFactors = FALSE
  )$Col_int,
  .con = DBI::ANSI()
)
#> <SQL> '1'
#> <SQL> NULL


glue_sql(
  "{Col_int}",
  Col_int = as.numeric(data.frame(
    Col_int = c(1L, NA_integer_),
    stringsAsFactors = FALSE
  )$Col_int),
  .con = DBI::ANSI()
)
#> <SQL> '1'
#> <SQL> NULL

glue_sql(
  "{Col_int}",
  Col_int = as.numeric(data.frame(
    Col_int = c(1, 2),
    stringsAsFactors = FALSE
  )$Col_int),
  .con = DBI::ANSI()
)
#> <SQL> 1
#> <SQL> 2

sessionInfo() with glue 1.31

#> R version 3.4.4 (2018-03-15)
#> Platform: x86_64-pc-linux-gnu (64-bit)
#> Running under: Ubuntu 16.04.4 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_US.UTF-8       LC_NUMERIC=C              
#>  [3] LC_TIME=en_US.UTF-8        LC_COLLATE=en_US.UTF-8    
#>  [5] LC_MONETARY=en_US.UTF-8    LC_MESSAGES=en_US.UTF-8   
#>  [7] LC_PAPER=en_US.UTF-8       LC_NAME=C                 
#>  [9] LC_ADDRESS=C               LC_TELEPHONE=C            
#> [11] LC_MEASUREMENT=en_US.UTF-8 LC_IDENTIFICATION=C       
#> 
#> attached base packages:
#> [1] stats     graphics  grDevices utils     datasets  methods   base     
#> 
#> other attached packages:
#> [1] glue_1.3.1
#> 
#> loaded via a namespace (and not attached):
#>  [1] compiler_3.4.4  backports_1.1.2 magrittr_1.5    rprojroot_1.3-2
#>  [5] DBI_1.0.0       tools_3.4.4     htmltools_0.3.6 yaml_2.2.0     
#>  [9] Rcpp_1.0.0      stringi_1.2.2   rmarkdown_1.9   knitr_1.20     
#> [13] stringr_1.3.1   digest_0.6.18   evaluate_0.11

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