"indicators must be 6-letter codes, the following are invalid: 999"
"indicators must be 6-letter codes, the following are invalid: 998, 999"
"indicators must be 6-letter codes, the following are invalid: all"
"areas codes must take the form XX or XX-YY, the following are invalid: 00"
"areas codes must take the form XX or XX-YY, the following are invalid: 00, 01"
"areas codes must take the form XX or XX-YY, the following are invalid: all"
"the following years are invalid: 10, 11"
"percentiles must take the form pXX or pXXpYY, the following are invalid: pAAp100"
"percentiles must take the form pXX or pXXpYY, the following are invalid: pAA, pBBp100"
"percentiles must take the form pXX or pXXpYY, the following are invalid: pAA, p1pBB"
"percentiles must take the form pXX or pXXpYY, the following are invalid: all"
"ages must be numerical codes between 100 and 999, the following are invalid: 10"
"ages must be numerical codes between 100 and 999, the following are invalid: 10, 11"
"ages must be numerical codes between 100 and 999, the following are invalid: all"
"population codes must be 'i', 'j', 'm', 'f', 't' or 'e', the following are invalid: 10"
"population codes must be 'i', 'j', 'm', 'f', 't' or 'e', the following are invalid: 10, ij"
"population codes must be 'i', 'j', 'm', 'f', 't' or 'e', the following are invalid: all"

`check_areas(c("00", "01"))` threw an error with unexpected message.
Expected match: "areas codes must take the form XX or XX-YY, the following are invalid: 00, 01"
Actual message: "Area codes must take the form XX, XX-YY, or XX-YYY. The following are invalid: 00, 01"

`check_areas(c("00", "AA", "01"))` threw an error with unexpected message.
Expected match: "areas codes must take the form XX or XX-YY, the following are invalid: 00, 01"
Actual message: "Area codes must take the form XX, XX-YY, or XX-YYY. The following are invalid: 00, 01"

`check_areas(c("AA", "all"))` threw an error with unexpected message.
Expected match: "areas codes must take the form XX or XX-YY, the following are invalid: all"
Actual message: "Area codes must take the form XX, XX-YY, or XX-YYY. The following are invalid: all"