Call logging

log.R

# Use: add `log_call("<function name")` to your functions

# TODO: Add to all functions in a namespace via `trace()`

indent <- new_environment(list(value = 0L))

log_call <- function(name, call = sys.call(-1), envir = parent.frame()) {
  srcref <- attr(call, "srcref")
  if (is.null(srcref)) {
    call_dep <- paste(gsub("^ +", "", deparse(call)), collapse = "")
    file_line <- ""
  } else {
    call_dep <- paste(gsub("^ +", "", as.charactfer(srcref)), collapse = "")
    filename <- attr(srcref, "srcfile")$filename
    if (identical(filename, "")) {
      filename <- "<unknown>"
    } else {
      filename <- basename(filename)
    }

    filename <- cli::format_inline("{.file {filename}:{srcref[[1]]}:{srcref[[2]]}}")
    file_line <- paste0(" (", filename, ")")
  }

  indent_str <- strrep(" ", indent$value)
  log <- paste0(name, "(): ", call_dep, file_line)

  writeLines(paste0(indent_str, "+", log))
  indent$value <- indent$value + 1L

  withr::defer(envir = envir, {
    indent$value <- indent$value - 1L
    writeLines(paste0(indent_str, "-", log))
  })
}