feat(picker.highlights): show color hash and highlight links

lua/snacks/picker/config/defaults.lua

@@ -1,6 +1,6 @@
 local M = {}
 
----@alias snacks.picker.Extmark vim.api.keyset.set_extmark|{col:number}
+---@alias snacks.picker.Extmark vim.api.keyset.set_extmark|{col:number, row?:number}
 ---@alias snacks.picker.Text {[1]:string, [2]:string?, virtual?:boolean}
 ---@alias snacks.picker.Highlight snacks.picker.Text|snacks.picker.Extmark
 ---@alias snacks.picker.format fun(item:snacks.picker.Item, picker:snacks.Picker):snacks.picker.Highlight[]

lua/snacks/picker/core/list.lua

@@ -396,6 +396,7 @@ function M:_render(item, row)
   for _, extmark in ipairs(extmarks) do
     local col = extmark.col
     extmark.col = nil
+    extmark.row = nil
     vim.api.nvim_buf_set_extmark(self.win.buf, ns, row - 1, col, extmark)
   end
 end

lua/snacks/picker/preview.lua

@@ -47,6 +47,11 @@ function M.preview(ctx)
   local lines = vim.split(ctx.item.preview.text, "\n")
   vim.api.nvim_buf_set_lines(ctx.buf, 0, -1, false, lines)
   ctx.preview:highlight({ ft = ctx.item.preview.ft })
+  for _, extmark in ipairs(ctx.item.preview.extmarks or {}) do
+    local e = vim.deepcopy(extmark)
+    e.col, e.row = nil, nil
+    vim.api.nvim_buf_set_extmark(ctx.buf, ns, (extmark.row or 1) - 1, extmark.col, e)
+  end
   ctx.preview:loc()
 end
 

lua/snacks/picker/source/vim.lua

@@ -167,8 +167,18 @@ function M.highlights()
       end
     end
     local code = {} ---@type string[]
+    local extmarks = {} ---@type snacks.picker.Extmark[]
+    local row = 1
     for _, def in ipairs(defs) do
+      for _, prop in ipairs({ "fg", "bg", "sp" }) do
+        local v = def.hl[prop]
+        if type(v) == "number" then
+          def.hl[prop] = ("#%06X"):format(v)
+        end
+      end
       code[#code + 1] = ("%s = %s"):format(def.group, vim.inspect(def.hl))
+      extmarks[#extmarks + 1] = { row = row, col = 0, hl_group = def.group, end_col = #def.group }
+      row = row + #vim.split(code[#code], "\n") + 1
     end
     items[#items + 1] = {
       text = vim.inspect(defs):gsub("\n", " "),
@@ -176,6 +186,7 @@ function M.highlights()
       preview = {
         text = table.concat(code, "\n\n"),
         ft = "lua",
+        extmarks = extmarks,
       },
     }
   end