Symlinked plugin with addon-info.json "name" may be added to the runtimepath twice

[glts]

This happens on an old MacVim 7.3, but not on newer versions of Vim.

Create a plugin with an addon-info.json file with an explicit "name", for example ~/code/vim-linked/addon-info.json:

{
    "name": "linked.vim",
    "version": "0.0.0",
    "dependencies": {
        "maktaba": {}
    }
}

Create a symlink to the plugin location, then start Vim with a vimrc that #GetOrInstalls the symlink location. (Here I used locations with different leaf dir names, but the same thing happens when the leaf dir names are the same.)

set nocompatible
source ~/.vim/maktaba/maktaba/bootstrap.vim
call maktaba#plugin#GetOrInstall('~/.vim/maktaba/linked')

Result. &rtp:

~/.vim,
~/code/vim-linked/,
~/.vim/maktaba/linked/,
/Applications/MacVim.app/Contents/Resources/vim/vimfiles,
/Applications/MacVim.app/Contents/Resources/vim/runtime,
/Applications/MacVim.app/Contents/Resources/vim/vimfiles/after,
~/.vim/after,
~/.vim/maktaba/maktaba

:echo maktaba#plugin#RegisteredPlugins():

['linked.vim', 'maktaba']

[dbarnett]

This should be fixed by #60 (almost ready to submit). I'm changing all the maktaba internal stuff to not touch rtp, so it will only be updated once, by your explicit call to maktaba#plugin#GetOrInstall.

That's a bit of a workaround. The detection would theoretically still fail to realize that '~/code/vim-linked/' and '~/.vim/maktaba/linked/' are the same path. Might still be worth investigating this bug independently and figuring out why maktaba doesn't understand these are the same path.

[glts]

Ah, cool.

FYI, I've tried the 'register' branch, and while the runtimepath problem goes away, my MacVim now starts with uncaught exceptions. Setup is the same as above.

Error detected while processing function maktaba#plugin#Enter..maktaba#plugin#Flag:
line    5:
E605: Exception not caught: ERROR(NotFound): Flag "plugin" not defined in plugin "linked.vim"
Error detected while processing function maktaba#plugin#Enter:
line   22:
E171: Missing :endif

Though this is probably a user error. I'll check later.

[dbarnett]

Hmm… I can't reproduce with vim 7.3.429. Followed your directions exactly. What version is your MacVim?

You can debug if you do :func /RegisterPlugin and then take that function name (e.g., <SNR>16_RegisterPlugin) and add breakadd func <SNR>NN_RegisterPlugin to your vimrc. I don't see any branch in the code where it would source instant files without first having defined the flags, but maybe it's somehow checking the wrong path for the plugin/ directory at the top of s:InitPlugin not finding it, or l:already_installed is messing up somehow?

[glts]

This is on a plain Vim 7.3 (no patches), which for a long time had been the latest supported MacVim 7.3 on Mac OS X 10.6.

I had some trouble getting debugging to work, but here is the plugin object as returned by maktaba#plugin#Get after starting up. The setup is exactly as given above.

{
  'AddonInfo': function('maktaba#plugin#AddonInfo'),
  'Flag': function('maktaba#plugin#Flag'),
  'GenerateHelpTags': function('maktaba#plugin#GenerateHelpTags'),
  'HasDir': function('maktaba#plugin#HasDir'),
  'HasFiletypeData': function('maktaba#plugin#HasFiletypeData'),
  'HasFlag': function('maktaba#plugin#HasFlag'),
  'IsLibrary': function('maktaba#plugin#IsLibrary'),
  'Load': function('maktaba#plugin#Load'),
  'MapPrefix': function('maktaba#plugin#MapPrefix'),
  'Source': function('maktaba#plugin#Source'),
  '_addon_info': {
    'author': 'author',
    'dependencies': {'maktaba': {}},
    'name': 'linked.vim',
    'version': '0.0.0',
  },
  '_entered': {
    'autoload': [],
    'ftplugin': {},
    'instant': [],
    'plugin': [],
  },
  'flags': {},
  'globals': {},
  'location': '/Users/glts/code/vim-linked/',
  'logger': { ... },
  'name': 'linked.vim',
}

Flags are indeed not defined, and the location is the dereferenced symlink. On a current Vim the location is /Users/glts/.vim/maktaba/linked/.

[glts]

Phhhh, this is almost certainly to do with the resolve problem prior to patch 7.3.194, discussed in #18 and #31.

https://github.com/google/maktaba/blob/7b25c31c1769576802ff49baf1ca88392c0d4a1a/autoload/maktaba/plugin.vim#L507-L525

[dbarnett]

Ah, okay, so this a bug independent of #60 and the register branch. We need working path resolving for all supported vim versions. Let's try to bisect what version of vim is affected and find a workaround (or find an implementation that works in both old and new vim).

[glts]

I wouldn't call this independent of #60 and the 'register' branch. The bug is in the new code, in fact on line 522 of the part I highlighted.

Changing

" If plugin is symlinked, register resolved path as custom location to avoid
" conflicts.
let l:resolved_location = s:Fullpath(resolve(a:plugin.location))

to

" If plugin is symlinked, register resolved path as custom location to avoid
" conflicts. As above, fnamemodify() is required to strip the trailing slash.
let l:resolved_location = s:Fullpath(resolve(fnamemodify(a:plugin.location, ':p:h')))

fixes the problem. The problem description is exactly the same as that given in the comment 15 lines above. I'm too lazy to open a pull req, can you fix it?

I don't know your reasoning behind requiring the trailing slashes in paths, but it does make life a little harder. Cheers.

[dbarnett]

Oh, I misunderstood then.

Should be fixed on the resolve branch now if you want to double-check I fixed it properly.

I don't know your reasoning behind requiring the trailing slashes in paths, but it does make life a little harder.

The reason we prefer explicit trailing slashes is that it makes the path unambiguously refer to a directory, which helps in path manipulation code like maktaba#path#Dirname to not get confused. It reduces the need for going to the filesystem to determine whether paths are supposed to refer to a file or directory, and also makes things behave better when referring to dirs that don't exist (yet).

[glts]

A-ok.