[feature] allow forcing usage of custom configured icons without icon font

[shmerl]

Description

I was trying to configure some basic symbols usage since I'm not using custom fonts, and this configuration didn't work as I expected:

         require("diffview").setup({
            icons = {
               folder_closed = "🗀",
               folder_open = "🗁",
            },
            signs = {
               fold_closed = "🞂",
               fold_open = "🞃",
               done = "✓"
            }
         })

What I got in result is that it used 🞂 and 🞃 for opened / closed folders. I expected it to be used for folds? And it didn't use folder_closed / folder_opened for folders.

Am I missing something here?

Thank you!

Expected behavior

Actual behavior

Steps to reproduce

Configure the plugin as shown above.

Health check

Output of :checkhealth diffview

iffview:                                   require("diffview.health").check() 
 
Checking plugin dependencies 
- ⚠ WARNING Optional dependency 'nvim-web-devicons' not found. 
 
Checking VCS tools 
- The plugin requires at least one of the supported VCS tools to be valid. 
- ✅ OK Git found. 
- ✅ OK Git is up-to-date. (2.49.0) 
- ⚠ WARNING Configured hg_cmd is not executable: 'hg' 
 
~

Log info

Relevant info from :DiffviewLog

############################
### PUT LOG CONTENT HERE ###
############################

Neovim version

NVIM v0.11.1
Build type: Release
LuaJIT 2.1.1741730670

Operating system and version

Debian testing

[shmerl]

I think I figured it out, it disables usage of icons if it doesn't detect the font. So I suppose I can as well just set use_icons to false to begin with and just use fold signs like this since it works well enough for file tree view:

         require("diffview").setup({
            signs = {
               fold_closed = "🞂",
               fold_open = "🞃",
               done = "✓"
            }
         })

It would be nicer if you could allow just skipping the font check altogether and simply allow configuring every single icon you use explicitly, there could be enough Unicode symbols for that I suppose.

[shmerl]

Alternatively, you can add a config key "force_icons", which when true will ignore lack of the font at least for icons that you allow to configure explicitly, such as folders.

[shmerl]

OK, I managed to make it work:

Would you accept a PR for this? Here is what I changed:

diff --git a/lua/diffview/config.lua b/lua/diffview/config.lua
index f1f6d0f..15c870a 100644
--- a/lua/diffview/config.lua
+++ b/lua/diffview/config.lua
@@ -42,6 +42,7 @@ M.defaults = {
   git_cmd = { "git" },
   hg_cmd = { "hg" },
   use_icons = true,
+  force_icons = false,
   show_help_hints = true,
   watch_index = true,
   icons = {
diff --git a/lua/diffview/scene/views/diff/render.lua b/lua/diffview/scene/views/diff/render.lua
index 3790a55..44de630 100644
--- a/lua/diffview/scene/views/diff/render.lua
+++ b/lua/diffview/scene/views/diff/render.lua
@@ -97,7 +97,7 @@ local function render_file_tree_recurse(depth, comp)
   dir:add_text(string.rep(" ", depth * 2))
   dir:add_text(ctx.collapsed and conf.signs.fold_closed or conf.signs.fold_open, "DiffviewNonText")
 
-  if conf.use_icons then
+  if conf.use_icons or conf.force_icons then
     dir:add_text(
       " " .. (ctx.collapsed and conf.icons.folder_closed or conf.icons.folder_open) .. " ",
       "DiffviewFolderSign"

And then in my config I did this:

         require("diffview").setup({
            force_icons = true,
            icons = {
               folder_closed = "🗀",
               folder_open = "🗁",
            },
            signs = {
               fold_closed = "🞂",
               fold_open = "🞃",
               done = "✓"
            }
         })