Assert that a data frame has exactly these columns — assert_column

Checks that x is a data frame whose column names are exactly columns, as a set. By default order does not matter.

Usage

assert_column_names(
  x,
  columns,
  ordered = FALSE,
  null_ok = FALSE,
  arg = rlang::caller_arg(x),
  call = rlang::caller_env()
)

x: Object to check.
columns: Character vector of the exact column names expected.
ordered: Single logical: if TRUE, the columns must also appear in the given order. Defaults to FALSE.
null_ok: Single logical. If TRUE, a NULL value passes the check without error. Use this for optional arguments that default to NULL. Defaults to FALSE, so NULL is rejected unless you opt in.
arg: Name used to refer to x in error messages. Defaults to the name of the expression passed as x.
call: Environment used as the error's call context. Defaults to the calling function, so errors point at the user's code.

The input x, invisibly.

assert_column_names(data.frame(a = 1, b = 2), c("a", "b"))