---
title: "Naming conventions for folders and files"
output: rmarkdown::html_vignette
vignette: >
  %\VignetteIndexEntry{Naming conventions for folders and files}
  %\VignetteEngine{knitr::rmarkdown}
  %\VignetteEncoding{UTF-8}
---

```{r, include = FALSE}
knitr::opts_chunk$set(
  collapse = TRUE,
  comment = "#>"
)
```

To make this easier to remember we choose the same name conventions for file names as for objects.
We acknowledge that these rules sometimes clash with requirements from other sources (e.g. `DESCRIPTION` in an R package, `README.md` on GitHub, `.gitignore` for git, ...).
In such case we allow the file names as required by R, git or GitHub.
When `check_filename()` does unfairly not allow a certain file or folder name, then please open an [issue on GitHub](https://github.com/inbo/checklist/issues) and motivate why this should be allowed.

## Rules for folder names

- Folder names should only contain lower case letters, numbers and underscore (`_`).
- They can start with a single dot (`.`).

## Rules for file names

- Base names should only contain lower case letters, numbers and underscore (`_`).
- File extensions should only contains lower case letters and numbers.
  Exceptions: file extensions related to R must have an upper case R (`.R`, `.Rmd`, `.Rd`, `.Rnw`, `.Rproj`).

## Rules for graphical file names

```{r, include = FALSE}
extensions <- sprintf("`%s`", checklist:::graphics_ext)
head(extensions, -1) |>
  paste(collapse = ", ") |>
  paste("and", tail(extensions, 1)) -> extensions
```


- Currently applies to files with these extensions: `r extensions`.
- Same rules except that you need to use a dash (`-`) as separator instead of an underscore (`_`).
  We need this exception because underscores cause problems with graphics files in certain situations.