pyenv initialization in .bash_profile vs. .bashrc (after release 2.0.0) - bash

Question

With the recent release of pyenv 2.0.0, the documentation currently recommends the following configuration for a bash shell:
# inside ~/.bash_profile
eval "$(pyenv init --path)"
# inside ~/.bashrc
eval "$(pyenv init -)"
If I'm not allowed to edit .bashrc on my system (for reasons completely unrelated to pyenv), what would be the drawbacks of just putting both inside my profile, like this:
# inside ~/.bash_profile
eval "$(pyenv init --path)"
eval "$(pyenv init -)"
I've been using it like this for a few hours, and I haven't noticed any issues (on MacOS, with a Homebrew installation of pyenv, and Python 3.6/3.7/3.8 virtual environments created with venv). I'm trying to understand what might be the drawbacks of configuring my system this way, and why the documentation makes such a big deal about using both .bash_profile and .bashrc.
Will configuring pyenv in this way cause problems for me in the future?

Answer 1

Bash only runs ~/.bash_profile when you start a login shell. When you start a new shell by typing bash or exec bash, its runs only ~/.bashrc. However, you can work around this easily by always starting new shells with bash -l or exec bash -l, which will make the new shell a login shell.
To find out whether it makes a difference whether you don't run eval "$(pyenv init -)" in non-login shells, let's have a look at what pyenv init - really does:
$ pyenv init -
export PYENV_SHELL=bash
source '/usr/local/Cellar/pyenv/2.0.0/libexec/../completions/pyenv.bash'
command pyenv rehash 2>/dev/null
pyenv() {
local command
command="${1:-}"
if [ "$#" -gt 0 ]; then
shift
fi
case "$command" in
rehash|shell)
eval "$(pyenv "sh-$command" "$#")"
;;
*)
command pyenv "$command" "$#"
;;
esac
}
Since export PYENV_SHELL=bash puts $PYENV_SHELL into the environment, it will get imported for your non-login shells, too. So, that doesn't make any difference.
As for the rest, it looks like the main thing you're missing out on is command line completion for pyenv. Other than that, there's just some special wrapping for pyenv shell and pyenv rehash.
So, as long as you don't use tab completion for pyenv nor use the commands pyenv shell and pyenv rehash in your non-login shells, then it should make no difference. But even if you do want to use those there, you can simply start the shell with bash -l or just run eval "$(pyenv init -)" manually.