Sequence in string to sequence string + separate rows

seq_string.R

library(tidyr)
library(dplyr)
library(purrr)

#' Create sequence from colon sepearted sequence in string format
#'
#' @param input character character vector with : based sequences 
#' in between comma separated numbers
#'
#' @return character
#'
#' @examples
#' colon_to_seq("1:3,4,5,6")
#' colon_to_seq("5:8,4,5,6")
#' colon_to_seq("1,2,3:5,6:10,11")
#' Create sequence from colon sepearted sequence in string format
#'
#' @param input character character vector with : based sequences 
#' in between comma separated numbers
#'
#' @return character
#'
#' @examples
#' colon_to_seq("1:3,4,5,6")
#' colon_to_seq("5:8,4,5,6")
#' colon_to_seq("1,2,3:5,6:10,11")
colon_to_seq <- function(input){
  seq_locs <- gregexpr("\\d+:\\d+", input)
  matched <- regmatches(input, seq_locs)[[1]]
  
  split_support <- function(text) {
    split_seq <- strsplit(text, ":")[[1]]
    paste(as.character(seq(split_seq[1], split_seq[2])), collapse = ",")
  }
  
  regmatches(input, seq_locs, invert = FALSE) <- list(map_chr(matched, split_support))
  input
}


# TESTING THE FUNTIONALITY
input_1 <- "1:3,4,5,6"
output_1 <- "1,2,3,4,5,6"

input_2 <- "5:8,4,5,6"
output_2 <- "5,6,7,8,4,5,6"

input_3 <- "4,5,6"
output_3 <- "4,5,6"

input_4 <- "6:10"
output_4 <- "6,7,8,9,10"

input_5 <- "1,2,3:5,6:10,11"
output_5 <- "1,2,3,4,5,6,7,8,9,10,11"

assertthat::are_equal(output_1, colon_to_seq(input_1))
assertthat::are_equal(output_2, colon_to_seq(input_2))
assertthat::are_equal(output_3, colon_to_seq(input_3))
assertthat::are_equal(output_4, colon_to_seq(input_4))

# Extending towards a dataframe
my_df <- as.data.frame(list("ID" = c(input_1,input_5,input_3), 
                            "val" = rep("b", 3)),
                       stringsAsFactors = FALSE)

output_df <- as.data.frame(list("ID" = c(output_1,output_5,output_3), 
                                "val" = rep("b", 3)),
                           stringsAsFactors = FALSE)

my_df %>% 
  rowwise() %>%
  mutate(ID = colon_to_seq(.data$ID)) %>%
  ungroup() %>%
  separate_rows(ID, sep = ",")