[ARROW-14902] [R] Update write_csv_arrow() to support all args of readr::write_csv() - ASF JIRA

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Details

Type: Improvement
Status: Open
Priority: Major
Resolution: Unresolved
Affects Version/s: None
Fix Version/s: None
Component/s: R
Labels:
None

External issue URL:
https://github.com/apache/arrow/issues/30427

Description

Currently (arrow version 6.0.1 and readr version 2.1.0) we only support a few of the readr::write_csv() arguments. Once ~~ARROW-13623~~ is fixed write_csv_arrow() will error if the user passes unsupported readr arguments.

The following arguments need CsvWriteOptions (see linked issues) in order to be exposed to R users:

na: string used for missing values. Defaults to NA. Missing values are never quoted; strings with the same value as na will always be quoted.
append: boolean. If {[FALSE}} will overwrite existing file. If TRUE will append to existing file. In both cases, if the file doesn't exist, a new file is created.
quote: how to handle fields which contain characters that need to be quoted:
- needed: only quote fields which need them
- all: quote all fields - I think this might be the implicit default behaviour for `write_csv_arrow()`
- none: never quote fields
escape: the type of escape to use when quotes are in the data:
- double: quotes are escaped by doubling them
- backslash: quotes are escaped by a preceding backslash
- none: quotes are not escaped
eol: the end of line character to use. Most commonly either "\n" for Unix style newlines, or "\r\n" for Windows style newlines.

Once these are enabled, update the signature of `write_csv_arrow()` and compare written files.
From ~~ARROW-13623~~ "I noticed we had a difference in quoting: readr doesn't quote strings by default but we do." Once we have more control over quoting, we could write some tests to make sure default behaviours between write_csv_arrow() and {{readr::write_csv()}} match.