inst/etc/z_legacy_code/find_python.R

In d-bohn/quantIm: Quantitative Assesment of Facial Images

#' Helper function to find python on user system
#'
#' @param python
#' @param condaenv
#'
#' @importFrom reticulate use_condaenv conda_list use_python
#'
find_python <- function(python, condaenv){
  if(hasArg(condaenv)){
    reticulate::use_condaenv(condaenv)
    condalist <- reticulate::conda_list()
    py_loc <- ifelse(condaenv %in% condalist$name,
                     condalist[condalist$name==condaenv,'python'],
                     NA)
    message('The python version this system is using is located at: ', py_loc)
  } else if(hasArg(python)){
    ## Try for homebrew first
    python_hb <- suppressWarnings( system('which python2', intern = TRUE) )
    ## If null...try default python
    if(!is.null(attr(python_hb,'status'))){
      py_locT <- system("which python", intern=TRUE)
      message('The python version this system is using is located at: ', py_loc)
      yn1 <- readline('Is this correct? (Y, N): ')
      ## If no, supply it
      if ((yn1 == 'n' | yn1 == 'N' | yn1 == 'NO' | yn1 == 'no' | yn1 == 'No') == TRUE) {
        py_locU <- readline('Please provide desired python location executable: ')
        py_loc <- py_locU
        reticulate::use_python(py_locU)
      } else {
        py_loc <- py_locT
        reticulate::use_python(py_locT)
      }
    } else{
      py_loc <- python_hb
      reticulate::use_python(python_hb)
    }
  } else {
    py_loc <- python
    reticulate::use_python(python)
  }
  return(py_loc)
}