New function add_padding() to avoid sprintf()

R/add_padding.R

@@ -0,0 +1,38 @@
+#' Add padding to string
+#'
+#' @param d vector of strings or numbers
+#' @param length final string length
+#' @param after if padding should be added after as opposed to default before
+#' @param pad padding string of length 1
+#'
+#' @return vector or character strings of same length.
+#' @export
+#'
+#' @examples
+#' add_padding(sample(1:200,5))
+add_padding <- function(d,length=NULL,after=FALSE,pad="0"){
+  if (!is.vector(d)) {
+    stop("Please supply vector")
+  }
+  
+  if (nchar(pad)!=1) {
+    stop("Padding value should be just a single character or digit")
+  }
+  
+  ns <- nchar(d)
+  
+  if (is.null(length)){
+    l <- max(ns)
+  } else {
+    l <- length
+  }
+  
+  ps <- unlist(lapply(l-ns,function(i){
+    paste(rep(pad,i),collapse="")}))
+  
+  if (after) {
+    paste0(d,ps)
+  } else {
+    paste0(ps,d)
+  }
+}

man/add_padding.Rd

@@ -0,0 +1,26 @@
+% Generated by roxygen2: do not edit by hand
+% Please edit documentation in R/add_padding.R
+\name{add_padding}
+\alias{add_padding}
+\title{Add padding to string}
+\usage{
+add_padding(d, length = NULL, after = FALSE, pad = "0")
+}
+\arguments{
+\item{d}{vector of strings or numbers}
+
+\item{length}{final string length}
+
+\item{after}{if padding should be added after as opposed to default before}
+
+\item{pad}{padding string of length 1}
+}
+\value{
+vector or character strings of same length.
+}
+\description{
+Add padding to string
+}
+\examples{
+add_padding(sample(1:200,5))
+}

tests/testthat/test-add_padding.R

@@ -0,0 +1,17 @@
+test_that("chunks_of_n returns correct", {
+  expect_length(add_padding(sample(1:200,5)),5)
+  
+  expect_equal(nchar(add_padding(sample(1:200,5),5)), rep(5,5))
+  
+  expect_equal(nchar(add_padding(
+    sample(1:200, 5), length = 5, after = TRUE
+  )), rep(5, 5))
+  
+  
+  ## Errors
+  expect_error(add_padding(matrix(sample(1:200,5)),5))
+  
+  expect_error(add_padding(matrix(sample(1:200,5)),5,pad = "123"))
+  
+  
+})