Unit-Testing with `{httptest}`

[GregorDeCillia]

There is already a first attempt to include unit tests for the STATcube API using {httptest} in #40 . The basic idea is to have a way to test the parsers and print methods for sc_table() and friends when submitting the package to CRAN.

One important question here is which cubes/databases should be used in the tests. One reccomendation is the "Gemeindedaten (Demo)" databse. However, in order to maximize code-coverage, some databases with annotations and missing values would be required. Unfortunately, the "Gemeindedaten (Demo)" database only provides missings/annotations of the kind "X: cross tabulation not allowed". Another useful thing would be to have different types of time variables (half year, month, week, quarter, year)

Canidate databases

• Foreign Trade includes annotations "T: Total Suppression" and "G: Disclosure control".
• LFS inclues annotations "S: samping error" and "N: value does not make sense" which are special annotations with underlying values.
• This tourism database contains several types of time variables with a hierarchy.