ARROW-15659 [R] strptime should return NA (not error) with format mismatch

[dragosmg]

This PR aligns arrow's binding to strptime() to base::strptime() when the value passed to the format argument does not match the data. Currently arrow errors, when it should return NA.

library(lubridate)
library(arrow)
library(dplyr)

df <- tibble(x = "2022-02-11")

df %>% 
  mutate(z = strptime(x, format = "%Y-%m %d"))
#> # A tibble: 1 × 2
#>   x          z     
#>   <chr>      <dttm>
#> 1 2022-02-11 NA

df %>% 
  record_batch() %>% 
  mutate(z = strptime(x, format = "%Y-%m %d")) %>% 
  collect()
#> Error: Invalid: Failed to parse string: '2022-02-11' as a scalar of type timestamp[ms]

^{Created on 2022-02-11 by the reprex package (v2.0.1)}

[github-actions]

https://issues.apache.org/jira/browse/ARROW-15659

[github-actions]

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[dragosmg]

I think several things are needed:

• new unit tests to show similar behaviour (returning NA in the same circumstances)
• update existing unit tests. These are not using compare_dplyr_binding() and are not catching the fact that Arrow's strptime binding returns an object of a different class (POSIXct, a double vector) that base::strptime() (POSIXlt, a list)

waldo::compare() does ignore class when ignore_attr = TRUE, but it can't ignore typeof. I'm not sure we want to change the type of object Arrow's strptime binding returns.

[dragosmg]

@jonkeane what do you think? Is the type of the object returned by strptime of concern? base::strptime() returns a list (POSIXlt), while the Arrow one returns an atomic vector. We hadn't caught this before as the unit tests for strptime did not compare the {dplyr} and {arrow} pipelines.

[jonkeane]

@jonkeane what do you think? Is the type of the object returned by strptime of concern? base::strptime() returns a list (POSIXlt), while the Arrow one returns an atomic vector. We hadn't caught this before as the unit tests for strptime did not compare the {dplyr} and {arrow} pipelines.

There are a few comments about this in the tests that reference this — I don't think it was unknown. POSIXlt is pretty unique to R (I'm sure there were other languages that have similar types), but they aren't super wide-spread, and Arrow doesn't support them directly (though you can see in the R package we make a (pseudo)-extension class for them).

[dragosmg]

This needs a rebase once #12732 gets merged.

[jonkeane]

A few questions about the tests

[ursabot]

Benchmark runs are scheduled for baseline = 64560af and contender = ba04e7f. ba04e7f is a master commit associated with this PR. Results will be available as each benchmark for each run completes.
Conbench compare runs links:
[Finished ⬇️0.0% ⬆️0.0%] ec2-t3-xlarge-us-east-2
[Finished ⬇️0.21% ⬆️0.04%] test-mac-arm
[Failed ⬇️0.0% ⬆️0.0%] ursa-i9-9960x
[Finished ⬇️0.04% ⬆️0.0%] ursa-thinkcentre-m75q
Buildkite builds:
[Finished] <https://buildkite.com/apache-arrow/arrow-bci-benchmark-on-ec2-t3-xlarge-us-east-2/builds/419| ba04e7f8 ec2-t3-xlarge-us-east-2>
[Finished] <https://buildkite.com/apache-arrow/arrow-bci-benchmark-on-test-mac-arm/builds/405| ba04e7f8 test-mac-arm>
[Failed] <https://buildkite.com/apache-arrow/arrow-bci-benchmark-on-ursa-i9-9960x/builds/405| ba04e7f8 ursa-i9-9960x>
[Finished] <https://buildkite.com/apache-arrow/arrow-bci-benchmark-on-ursa-thinkcentre-m75q/builds/415| ba04e7f8 ursa-thinkcentre-m75q>
[Finished] <https://buildkite.com/apache-arrow/arrow-bci-benchmark-on-ec2-t3-xlarge-us-east-2/builds/418| 64560af6 ec2-t3-xlarge-us-east-2>
[Finished] <https://buildkite.com/apache-arrow/arrow-bci-benchmark-on-test-mac-arm/builds/404| 64560af6 test-mac-arm>
[Finished] <https://buildkite.com/apache-arrow/arrow-bci-benchmark-on-ursa-i9-9960x/builds/404| 64560af6 ursa-i9-9960x>
[Finished] <https://buildkite.com/apache-arrow/arrow-bci-benchmark-on-ursa-thinkcentre-m75q/builds/414| 64560af6 ursa-thinkcentre-m75q>
Supported benchmarks:
ec2-t3-xlarge-us-east-2: Supported benchmark langs: Python, R. Runs only benchmarks with cloud = True
test-mac-arm: Supported benchmark langs: C++, Python, R
ursa-i9-9960x: Supported benchmark langs: Python, R, JavaScript
ursa-thinkcentre-m75q: Supported benchmark langs: C++, Java