Verify that reference columns are present if they are required for any calculation

[billdenney]

At this location:

pknca/R/check.intervals.R

Line 65 in e241322

# Now check specific columns

Please:

• Check if any reference is needed
• If so, require that a column named "interval_id" is present in the intervals (error if not)
• If so, verify that the reference col has a valid "interval_id" in it (cannot be the interval_id of the current row)

The tests will likely look something like:

# Okay because no secondary parameters are present
check.interval.specification(data.frame(start = 0, end = 1, cmax = TRUE)
# Error that no `clr.last_ref_interval_id` column is present
check.interval.specification(data.frame(start = 0, end = 1, clr.last = TRUE)
# Error that no `interval_id` column is present
check.interval.specification(data.frame(start = 0, end = 1, clr.last = TRUE, clr.last_ref_interval_id = "a")
# Error that `clr.last_ref_interval_id` column cannot be `NA` when `clr.last` is TRUE
check.interval.specification(data.frame(start = 0, end = 1, clr.last = TRUE, clr.last_ref_interval_id = NA)
# Error that `clr.last_ref_interval_id` is not present in the `interval_id` column
check.interval.specification(data.frame(start = 0, end = 1, clr.last = TRUE, clr.last_ref_interval_id = "a", interval_id = "b")
# Error that `clr.last_ref_interval_id` and `interval_id` column must be the same `class()`
check.interval.specification(data.frame(start = 0, end = 1, clr.last = TRUE, clr.last_ref_interval_id = "a", interval_id = 1)
# Success
check.interval.specification(data.frame(start = 0, end = 1, clr.last = c(FALSE, TRUE), clr.last_ref_interval_id = c(NA, "a"), interval_id = c("a", NA))

Follows #491
Related to #76