skip_on_oldrel()

[lionel-]

To skip tests on old R releases:

skip_on_oldrel <- function(version, msg = NULL) {
  if (utils::packageVersion("base") < version) {
    msg <- msg %||% paste("R version too old:", version)
    skip(msg)
  }
}

[hadley]

I think we should generalise this to:

skip_on_r_version("= 3.1")
skip_on_r_version(">= 3.1")

etc

[gaborcsardi]

skip_on_r_version("==", "3.1")
skip_on_r_version("<=", "3.1")

etc. is easier to implement (no parsing needed) , and just as easy to write, and it is also easier to write programmatically. I think.

[lionel-]

Good idea. Going further, making it a functional would be even easier to implement, more flexible (it'd accept arbitrary comparison functions which could handle edge cases more easily) and more idiomatic for R:

skip_on_r_version(`==`, "3.1")
skip_on_r_version(my_predicate, "3.1")

[hadley]

@lionel- only a limited number of operators have been implemented for working with version objects, so I'd rather keep it simple for now

[kevinushey]

What about just punting to a more general skip_if, e.g.

skip_if(getRversion() == "3.1.0")

The skip_on_r_version() signature seems easy to get wrong as a user.

[hadley]

The advantage of a more specific method is a better message, but skip_if() seems worthwhile even if we do have skip_on_r_version().

[hadley]

Comparing these options:

skip_if(getRversion() == "3.1.0")
skip_on_r_version(`==`, "3.1.0")

I don't think the more specific skip is any more appealing.

[gaborcsardi]

Maybe the message would be nicer for the second one?