Tests adapted from https://stackoverflow.com/q/31987023/13530036
and from https://stackoverflow.com/a/38938416/13530036 .
- Test when CALL with a label containing /? actually calls GOTO's help,
and test when CALL's help is displayed instead.
- Test when CALL with a label containing /?, but specified by variables,
do NOT trigger GOTO's or CALL's help.
- Test the effect of the presence of escape carets in CALL label string.
- Test that CALL indeed supports double delayed expansion. Adapted from
https://stackoverflow.com/a/31990563/13530036 .
- Tests for GOTO across IF parenthesized block (parser test with line
continuation at closing parenthesis).
- Tests for showing how FOR-loops stop when a GOTO is encountered.
- Tests for EXIT command within IF block.
