fix(#3015): dynamic width no longer truncates on right_align icons

[simonmandlik]

Fixes #3015

[alex-courtis]

Thanks for the fix, however I'm having trouble replicating and validating it.

Please provide a clean room configuration and instructions on how I can demonstrate the fix with it.

[simonmandlik]

Instructions:

1. run nvim -nu minimal.lua
2. Edit the longest file in any git repo. Here, I use nvim-tree directly so I change something in .release-please-manifest.json so that it get a right-aligned icon
3. This is the bug

Even though the max width is set to 100%, the whole filename is not shown due to the icon covering a part of it.

With this PR, it looks like this

minimal.lua:

vim.g.loaded_netrw = 1
vim.g.loaded_netrwPlugin = 1

vim.cmd([[set runtimepath=$VIMRUNTIME]])
vim.cmd([[set packpath=/tmp/nvt-min/site]])
local package_root = "/tmp/nvt-min/site/pack"
local install_path = package_root .. "/packer/start/packer.nvim"
local function load_plugins()
  require("packer").startup({
    {
      "wbthomason/packer.nvim",
      -- "~/Downloads/nvim-tree.lua",
      "nvim-tree/nvim-tree.lua",
      "nvim-tree/nvim-web-devicons",
    },
    config = {
      package_root = package_root,
      compile_path = install_path .. "/plugin/packer_compiled.lua",
      display = { non_interactive = true },
    },
  })
end
if vim.fn.isdirectory(install_path) == 0 then
  print("Installing nvim-tree and dependencies.")
  vim.fn.system({ "git", "clone", "--depth=1", "https://github.com/wbthomason/packer.nvim", install_path })
end
load_plugins()
require("packer").sync()
vim.cmd([[autocmd User PackerComplete ++once echo "Ready!" | lua setup()]])
vim.opt.termguicolors = true
vim.opt.cursorline = true

_G.setup = function()
  require("nvim-tree").setup({
    view = {
      width = {
        min = -1,
        max = "100%",
        padding = 0
      }
    },
    renderer = {
      icons = {
        git_placement = "right_align"
      }
    }
  })
end

[simonmandlik]

For what it's worth, this is not a solution I'm completely satisfied with. I placed the fix into View.grow and so upon every call of NvimTreeOpen the width is computed correctly. However, once I switch from the nvim-tree buffer to a different buffer, it gets resized back. This is because in such case, View.grow is called but for some reason there are no longer extmarks for right-aligned icons in the NvimTreeExtmarks namespace.

Screen.Recording.2024-12-11.at.19.11.49.mov

Another problem I could observe is that when nvim tree buffer is open and a new "after" icon is added (e.g. from LSP), the View.grow function doesn't have extmarks available either. Here I add both error diagnostic ("after") and git modified ("right_align") icon at the same time and the width is computed incorrectly. Only after I reopen the nvim tree buffer, it is correct again:

Screen.Recording.2024-12-11.at.19.27.07.mov

I don't know the internals of nvim-tree to be able to fix these, so I would appreciated some guidance here. Or I would be happy with merging this PR as is since I almost always close nvim tree rightaway and so the issues above do not bother me.

[simonmandlik]

Addressed the CI issues

[alex-courtis]

This change does address the issue for width whilst focused. Unfortunately the width when changing is a regression.

View is quite fragile. It is targeted for a refactor during https://github.com/orgs/nvim-tree/projects/1 however that will not address this issue.

A full solution is desirable, let's see what we can come up with.

[alex-courtis]

Works nicely for a variety of width cases.
Many thanks for resolving this one!