fix(lsp): codeActions not found if multiple clients are active

[carloskiki]

This fixes #744, which was thought to be caused by "copilot.vim", but actually happens anytime rust-analyzer does not have id: 1. We thought that this case was already handled (see: #744 (comment)), but it turns out that it wasn't.

According to the lua manual:

ipairs (t)

Returns three values (an iterator function, the table t, and 0) so that the construction

 for i,v in ipairs(t) do body end

will iterate over the key–value pairs (1,t[1]), (2,t[2]), ..., up to the first absent index. (emphasis mine).

What happens is that the result table returned by

vim.lsp.buf_request_all(0, 'textDocument/codeAction', params, function(results, ctx) 
-- handle `result` table.
end)

is sparse with respect to the LSPs that return a codeAction table. So consider rust-analyzer has id: 2, and the LSP with id: 1 does not return a codeAction table (presumably because the lsp is not made for rust files). Then ipairs will stop at index 1 and return nil, since it stops at the first absent index.

This PR fixes the bug by indexing only the codeActions provided by rust-analyzer.

@mrcjkb, when you tested out with null-ls, I believe you simply got lucky and rust-analyzer happened to be the lsp with id: 1.

[github-actions]

Review Checklist

Does this PR follow the Contribution Guidelines? Following is a partial checklist:

Proper conventional commit scoping:

• For example, fix(lsp): some lsp-related bugfix

• Pull request title has the appropriate conventional commit prefix.

If applicable:

• Tested
  • Tests have been added.
  • Tested manually (Steps to reproduce in PR description).
• Updated documentation.

[mrcjkb]

Thanks for troubleshooting.

issue: We want to display all code actions, not just the rust-analyzer ones.
I believe a simpler fix would be to leave the code as is, but to use pairs instead of ipairs.

todo: Please change the commit message and PR title to comply with the conventional commits specification (see the bot comment).

[mrcjkb]

Thanks 🙏