These printed "Unknown error while evaluating command substitution".
Now they print something like
```
fish: for: status: cannot overwrite read-only variable
for status in foo; end
^~~~~^
in command substitution
fish: Invalid arguments
echo (for status in foo; end)
^~~~~~~~~~~~~~~~~~~~~~~^
```
for `echo (for status in foo; end)`
This is, of course, still not *great*. Mostly the `fish: Invalid
arguments` is basically entirely redundant.
An alternative is to simply skip the error message, but that requires some
more scaffolding (describe_with_prefix adds some error messages on its
own, so we can't simply say "don't add the prefix if we don't have a
message")
(cherry picked from commit 1b5eec2af6)
This makes it so
```fish
if -e foo
# do something
end
```
complains about `-e` not being a command instead of `end` being used
outside of an if-block.
That means both that `-e` could now be used as a command name (it
already can outside of `if`!) *and* that we get a better error!
The only way to get `if` to be a decorated statement now is to use `if
-h` or `if --help` specifically (with a literal option).
The same goes for switch, while and begin.
It would be possible, alternatively, to disallow `if -e` and point
towards using `test` instead, but the "unknown command" message should
already point towards using `test` more than pointing at the
"end" (that might be quite far away).
Unfortunately print_hints was true *by default* - so for all builtins
that didn't pass it it would now be false instead.
This resulted in the trailer missing, which includes the line number
and context. So if you ran a script that includes `bind -M` the error
message would now just be "bind: -M: option requires an argument",
with no indication as to where.
This reverts commit 8a50d47a46.
Fixes ommitted newline char shown after complete -n'(foo)'
Also axes the 'contains syntax errors' line before the error.
Update tests
before
> complete -n'(foo)'
complete: Condition '(foo)' contained a syntax error
complete: Command substitutions not allowed⏎
after
> complete -n'(foo)'
complete: -n '(foo)': command substitutions not allowed here
String tokens are subdivided by command substitutions. Some syntax errors
can occur in the gap between two command substitutions. Make the caret point
to the start of that gap, instead of the token start.
This used to call exec_subshell, which has two issues:
1. It creates a command substitution block which shows up in a stack
trace
2. It does much more work than necessary
This removes a useless "in command substitution" from an error message
in an autoloaded file, and it speeds up autoloading a bit (not
measurable in actual benchmarks, but microbenchmarks are 2x).
This fixes a regression about where we report errors:
echo error(here
old: ^
fixed: ^
Commit 0c22f67bd (Remove the old parser bits, 2020-07-02) removed
uses of "error_offset_within_token" so we always report errors at
token start. Add it back, hopefully restoring the 3.1.2 behavior.
Note that for cases like
echo "$("
we report "unbalanced quotes" because we treat the $( as double
quote. Giving a better error seems hard because of the ambguity -
we don't know if quote is meant to be inside or outside the command
substitution.
Like the $status commit, this would add the offset to already existing
errors, so
```fish
(foo)
(bar)
something
```
would see the "(foo)" error, store the correct error location, then
see the "(bar)" error, and *add the offset of (bar)* to the "(foo)"
error location.
Solve this by making a new error list and appending it to the existing
ones.
There's a few other ways to solve this, including:
- Stopping after the first error (we only display the first anyway, I
think?)
- Making it so the source location has an "absolute" flag that shows
the offset has already been added (but do we ever need to add two offsets?)
I went with the simpler fix.
This would break the location of any prior errors without doing
anything of value.
E.g.
```fish
echo foo | exec grep # this exec is not allowed!
$status
somethingelse # The error might be found here!
```
Would apply the offset of `$status` to the offset of `exec`, locating
the error for `exec` somewhere after $status!
