Testing of caret location in diagnostic message is currently made with
CHECK directive with the following general format:
CHECK: {{^ \^$}}
James Henderson suggested the following would be more readable:
CHECK: {{^}} ^{{$}}
and when whole lines can be matched (as is the case for command-line
testing where error messages do not include path):
CHECK: ^
using the option --match-full-lines.
This commit implements these 2 changes on all existing caret position
tests. It also aligns the caret to the character it is trying to match
in the above line.
In this context, where exactly is the caret actually pointing at? Can spaces be added to one or more lines to get the caret to nicely line up?