bug#54603: 29.0.50; [PATCH] Eshell's external pipe module interferes with other argument parsing hooks

[Jim Porter]

On 3/31/2022 3:48 PM, Sean Whitton wrote:
> Thank you for testing.  In the meantime, I've thought it all through
> some more, and I think that your original idea of catching the
> 'eshell-incomplete is the right thing, assuming all tests pass.
>
> I think the error should be caught inside the `or', though?  The idea
> would be that if eshell-incomplete is thrown within one of the
> disjuncts, that disjunct should return nil.

Hmm, that's an interesting thought. Maybe this code could be more 
particular about what parse function it calls. Since each of the 
function calls here:

                         (while (or (eshell-parse-lisp-argument)
                                    (eshell-parse-backslash)
                                    (eshell-parse-double-quote)
                                    (eshell-parse-literal-quote)))

correspond to a particular token here (earlier in the source):

                               (re-search-forward
                                "\\(?:(\\|#?'\\|\"\\|\\\\\\)" bound t)))

perhaps it would be better to match the function call to the 
corresponding token. That is, if we see a "#?", we call 
`eshell-parse-lisp-argument', and so on. See the attached patch, which 
works in my tests (and passes all the existing Eshell unit tests).

0001-Make-Eshell-s-extpipe-more-lenient-when-looking-for-.patch
Description: Text document