Re: Install bnf-mode from the tar archive

[Stefan Monnier <monnier@iro.umontreal.ca>]

> I have managed to fix the issue just by replacing bsdtar by GNU tar.

I guess that deserves a bug report (the bug is not in
the package manager but in tar-mode.el which seems not to support some
of the formats used by bsdtar).


        Stefan


> For the full list of changes refer to:
> https://github.com/sergeyklay/bnf-mode/commit/309f05a781dc05999e8f0530f23089f38dd0fde6
>
> On 1/18/20 5:08 PM, Serghei wrote:
>> Hello,
>>
>> I am the bnf-mode[1] creator.  I am trying to figure out what
>> happens when I install the mode from the tar archive.  Frankly
>> speaking, I get a strange error message.
>>
>> You can see the fresh Makefile I use to create tar archive at GitHub
>> repo[2].  All I need to create a tar archive is a command
>> `make package'.  And it seems it works as expected.  However, after
>> creating the archive, I was failed to install it.  After changing
>> this line[3] as follows:
>>
>> diff --git a/Makefile b/Makefile
>> index c04c01c..d11ac3d 100644
>> --- a/Makefile
>> +++ b/Makefile
>> @@ -122,7 +122,8 @@ package: $(PACKAGE_NAME).tar
>>
>>  .PHONY: install
>>  install: $(PACKAGE_NAME).tar
>> -       $(EMACS) --batch -l package -f package-initialize --eval
>> "(package-install-file \"$(PWD)/$(PACKAGE_NAME).tar\")"
>> +       $(EMACS) --batch -l package -f package-initialize --eval \
>> +               "(let ((debug-on-error t))(package-install-file
>> \"$(PWD)/$(PACKAGE_NAME).tar\"))"
>>
>>  .PHONY: help
>>  help: .title
>>
>> I got the following debug trace:
>>
>> $ make install
>> Parsing tar file...
>> Parsing tar file...done
>> Debugger entered--Lisp error: (wrong-type-argument arrayp nil)
>>   tar--describe-as-link(nil)
>>   tar--check-descriptor(nil)
>>   tar-get-file-descriptor("bnf-mode-0.4.3/PaxHeader/PaxHeader-pkg.el")
>>   package-tar-file-info()
>>   package-install-from-buffer()
>>   package-install-file("/home/klay/work/bnf-mode/bnf-mode-0.4.3.tar")
>>   (let ((debug-on-error t)) (package-install-file
>> "/home/klay/work/bnf-mode/bnf-mode-0.4.3.tar"))
>>   eval((let ((debug-on-error t)) (package-install-file
>> "/home/klay/work/bnf-mode/bnf-mode-0.4.3.tar")))
>>   command-line-1(("-l" "package" "-f" "package-initialize" "--eval"
>> "(let ((debug-on-error t))(package-install-file
>> \"/home/klay/work/bnf-mode/bnf-mode-0.4.3.tar\"))"))
>>   command-line()
>>   normal-top-level()
>>
>> make: *** [Makefile:125: install] Error 255
>>
>> I have no idea what is PaxHeader/PaxHeader-pkg.el and even stranger
>> that after inspecting `tar-mode' I found this:
>>
>> (defun tar-get-file-descriptor (file)
>>   ;; Used by package.el.
>>   (let ((desc ()))
>>     (dolist (hdr tar-parse-info)
>>       (when (equal file (tar-header-name hdr))
>>         (setq desc hdr)))
>>     (tar--check-descriptor desc)
>>     desc))
>>
>> As you can see without any validation `desc' was passed to
>> `tar--check-descriptor` defun.  The `tar--check-descriptor` is just
>> calls `tar--describe-as-link`:
>>
>> (defun tar--check-descriptor (descriptor)
>>   (let ((link-desc (tar--describe-as-link descriptor)))
>>     (when link-desc
>>       (error "This is %s, not a real file" link-desc))))
>>
>> And finally it calls `tar-header-link-type':
>>
>> (defun tar--describe-as-link (descriptor)
>>   (let ((link-p (tar-header-link-type descriptor)))
>>     (if link-p
>> 	(cond ((eq link-p 5) "a directory")
>>               ((eq link-p 20) "a tar directory header")
>>               ((eq link-p 28) "a next has longname")
>>               ((eq link-p 29) "a multivolume-continuation")
>>               ((eq link-p 35) "a sparse entry")
>>               ((eq link-p 38) "a volume header")
>>               ((eq link-p 55) "a pax global extended header")
>>               ((eq link-p 72) "a pax extended header")
>>               (t "a link")))))
>>
>> I will be happy for any help and tips in the right direction.
>>
>> N.B. My GNU Emacs version is 26.3 on Debian/GNU Linux 10.
>>
>>
>> [1]: https://elpa.gnu.org/packages/bnf-mode.html
>> [2]:
>> https://github.com/sergeyklay/bnf-mode/blob/87c779851e44aab6639cdf2ab699aa9cd41f97c7/Makefile
>> [3]:
>> https://github.com/sergeyklay/bnf-mode/blob/87c779851e44aab6639cdf2ab699aa9cd41f97c7/Makefile#L125
>>
>> --
>> Serghei
>>
>>