Tabs on continuation lines break GAP's testing

[markuspf]

if one uses tab characters on continuation lines in a test file, this confuses GAP:

gap> f := function()
>\tlocal a;
>\tif a = 0 then
>\t\tError("a is zero");
>\tfi;
> end;;

########> Diff in tab.tst:1         
# Input is:
f := function()
	local a;
		Error("a is zero");
end;;
# Expected output:
>	if a = 0 then
>	fi;
# But found:
########
false

[ChrisJefferson]

There is another bug here, which I think is making this one harder to spot. GAP allows continuation lines in the middle of the output, and puts them as part of the input.

gap> x := 2 +
>	cheese
> 2;
3

gives:

########> Diff in t.tst:1           
# Input is:
x := 2 +
2;
# Expected output:
>	cheese
3
# But found:
4
########
false

[ChrisJefferson]

This issue has been improved somewhat. Further improves were unfortunately difficult due to the fact that some package rely on not this specific case, but similar cases where tests are formatted strangely. Therefore I think we should close this as "as fixed as it will get".

EDIT: Came up with a slightly hacky idea, #3375