Wildcard errors are only reported interactively, and they're also not
really errors. Commands with multiple wildcards would in fact continue
executing if at least one wildcard matched, which is quite surprising.
But they would report an error if there is only one wildcard in the
arguments list and the wildcard has no match, even if there are other
remaining arguments.
Given this inconsistency, and given that sh does not stop execution if a
wildcard fails to match, it seems better to allow execution to continue.
This is better from a scripting perspective anyway, as it means
constructs like `set -l paths foo/*.txt` will actually create the
variable (with an empty value) instead of skipping the `set`
altogether and perhaps causing subsequent code to read or modify a
global or universal variable.
parse_error_list_t through all of the expand functions, enabling them to
report errors more directly. Improve aspects of error reporting for
expansion failures.
