Conversion scope does not work in `py_to_r.pandas.core.frame.DataFrame`

[rcannood]

With reticulate 1.36.0, py_to_r.pandas.core.frame.DataFrame seems to no longer listen to its conversion scope.

This becomes an issue when using the anndata R package, which defines a py_to_r.pandas.core.indexes.base.Index function. As such, a round trip conversion from data.frame to a pandas DataFrame no longer works with reticulate 1.36, whereas this did use to work with reticulate 1.35.

Minimum reproducible example

# check out reticulate origin/main
devtools::load_all(".")

df <- data.frame(
  row.names = c("s1", "s2"),
  group = c("a", "b")
)
py_to_r(r_to_py(df))
#    group
# s1     a
# s2     b

library(anndata)

py_to_r(r_to_py(df))
# Error: Expected a python object, received a character

Error does not occur with Reticulate v1.35

# check out reticulate v1.35.0
devtools::load_all(".")

df <- data.frame(
  row.names = c("s1", "s2"),
  group = c("a", "b")
)
py_to_r(r_to_py(df))
#    group
# s1     a
# s2     b

library(anndata)

py_to_r(r_to_py(df)) # works as intended
#    group
# s1     a
# s2     b

Proposed solution

This issue is related to dynverse/anndata#28. I could implement a fix in anndata by removing the anndata::py_to_r.pandas.core.indexes.base.Index function. However, I feel like reticulate::py_to_r.pandas.core.frame.DataFrame should not be affected by the existence of the anndata py_to_r function, or am I mistaken?

Thanks for your input!

Kind regards,
Robrecht

[t-kalinowski]

Thanks for reporting! I was able to reproduce, and a fix is in main now.

[rcannood]

Thanks for the amazingly quick response @t-kalinowski !

Given that reticulate 1.36 was only just released, do you have any idea when do you think we could expect this fix to be released on CRAN?

[t-kalinowski]

The plan is to another CRAN release approximately 1 month from now.

[rcannood]

Given that this bug completely breaks anndata, would it be possible to create bug fix release sooner than that? 😬

[t-kalinowski]

I can submit next week, we'll see if CRAN complains.

[eddelbuettel]

It's all good. You twisted my arm to get RcppArmadillo out 'outside of schedule' now you are offering the same to @rcannood and anndata. Karma comes around and goes around, and we keep the wheels on spinning ...

[t-kalinowski]

On CRAN now

[rcannood]

🎊 Fantastic! You're a hero!