How is py_binary defined?

[allsey87]

I am a bit confused about how py_binary is defined. It seems that you can use this function in Bazel without importing anything, but it is also possible to override this default provided py_binary with a version from rules_python by loading it in. Does py_binary refer to different implementations in these two cases? If so, where are the differences between these implementations documented?

[rickeylev]

You've pretty much got it.

Bazel provides an implementation of the core python rules. However, they are being moved out of Bazel and into rules_python. Rules_python is a drop in replacement for the old rules built into bazel. The two implementations have almost identical behavior. There's not many differences and they are pretty minor differences (rules_python probably has a few fixes and features beyond it, actually). There's an issue in the Bazel repo that has a list of differences, but I'm on mobile and can't find it.

Eventually, Bazel will remove the built-in implementations. I'm not sure when that'll happen. Hopefully Bazel 8.

[allsey87]

I think this is the issue that you were referencing: bazelbuild/bazel#15897