feat(rocks): use hererocks to install luarocks when luarocks is not found

lua/lazy/core/config.lua

@@ -49,6 +49,8 @@ M.defaults = {
     enabled = true,
     root = vim.fn.stdpath("data") .. "/lazy-rocks",
     server = "https://nvim-neorocks.github.io/rocks-binaries/",
+    -- use hererocks to install luarocks.
+    hererocks = vim.fn.executable("luarocks") == 0,
   },
   dev = {
     ---@type string | fun(plugin: LazyPlugin): string directory where you store your local plugin projects

lua/lazy/core/meta.lua

@@ -33,7 +33,9 @@ function M:load_pkgs()
   if not Config.options.pkg.enabled then
     return
   end
+  local have_rockspec = false
   for _, pkg in ipairs(Pkg.get()) do
+    have_rockspec = have_rockspec or pkg.source == "rockspec"
     local meta, fragment = self:add(pkg.spec)
     if meta and fragment then
       meta._.pkg = pkg
@@ -46,6 +48,12 @@ function M:load_pkgs()
       self.pkgs[pkg.dir] = fragment.id
     end
   end
+  if have_rockspec then
+    local hererocks = Pkg.hererocks()
+    if hererocks then
+      self:add(hererocks)
+    end
+  end
 end
 
 --- Remove a plugin and all its fragments.

lua/lazy/core/plugin.lua

@@ -264,8 +264,10 @@ function M.update_rocks_state()
   end)
 
   for _, plugin in pairs(Config.plugins) do
-    if plugin._.pkg and plugin._.pkg.source == "rockspec" and plugin.build == "rockspec" then
+    if plugin.build == "rockspec" then
       plugin._.build = not installed[plugin.name]
+    elseif plugin.name == "hererocks" then
+      plugin._.build = not vim.uv.fs_stat(Config.options.rocks.root .. "/hererocks")
     end
   end
 end