Require Existing Files

Validates that every path of a character value exists and is a file. Found: shows the normalized path of the first offender, so a relative path resolved against the wrong working directory is visible.

Usage

require_file_exists(restriction, extension = NULL)

Arguments

restriction

a restriction object.

extension

optional character vector of accepted extensions, with or without the leading dot, compared case-insensitively. Adds a second step that checks the extension.

Value

The modified restriction object.

Details

Non-character input fails with a type error. NA paths are skipped; chain require_no_na() to reject them.

See also

Other file checks: require_dir_exists(), require_readable(), require_writable()

Examples

csv_in <- restrict("path") |> require_file_exists(extension = "csv")
tmp <- tempfile(fileext = ".csv")
invisible(file.create(tmp))
csv_in(tmp)
try(csv_in(file.path(tempdir(), "missing.csv")))
#> Error : path: must be an existing file
#>   Found: "/tmp/RtmplIFvmg/missing.csv"