[ARROW-10463] [R] Better messaging for currently unsupported CSV options in open_dataset

• Type: Bug
• Status: Resolved
• Priority: Minor
• Resolution: Fixed
• Affects Version/s: 2.0.0
• Fix Version/s: 3.0.0
• Component/s: R
• Labels: pull-request-available
• External issue URL: https://github.com/apache/arrow/issues/26439
• Assignee: Ian Cook
• Reporter: Gabriel Bassett
• Created: 02/Nov/20 14:32
• Updated: 11/Jan/23 08:13
• Resolved: 12/Jan/21 03:31

Description

While read_csv_arrow()'s signature matches readr,  the readr_to_csv_parse_options() function (called by way of open_dataset()) only appears to capture a subset of those options:

(https://github.com/apache/arrow/blob/883eb572bc64430307112895976ba79df10c8c7d/r/R/csv.R#L464)

readr_to_csv_parse_options <- function(delim = ",",
 quote = '"',
 escape_double = TRUE,
 escape_backslash = FALSE,
 skip_empty_rows = TRUE)

I ran into this trying to use a non-standard 'na' value:

 

open_dataset("/path/to/csv/directory/", schema = sch, partitioning=NULL, format="csv", delim=";", na="\\N", escape_backslash=TRUE, escape_double=FALSE`)
Error in readr_to_csv_parse_options(...) : unused argument (na = "\\N")

 

Issue Links

• relates to: ARROW-8631 [C++][Dataset] Add ConvertOptions and ReadOptions to CsvFileFormat
• links to: GitHub Pull Request #9143