fix: util.root_pattern priorities pattern order

Instead of traversing the filesystem upwards once and
returning the first match of all the patterns, it traverses
the filesystem upwards once for each pattern. This means
that the order of the patterns provided matters, and the
highest priority patterns should be put first. Also updated
corresponding tests.

lua/lspconfig/util.lua

@@ -250,19 +250,22 @@ end
 
 function M.root_pattern(...)
   local patterns = vim.tbl_flatten { ... }
-  local function matcher(path)
+  return function(startpath)
+    startpath = M.strip_archive_subpath(startpath)
     for _, pattern in ipairs(patterns) do
-      for _, p in ipairs(vim.fn.glob(M.path.join(M.path.escape_wildcards(path), pattern), true, true)) do
-        if M.path.exists(p) then
-          return path
+      local match = M.search_ancestors(startpath, function(path)
+        for _, p in ipairs(vim.fn.glob(M.path.join(M.path.escape_wildcards(path), pattern), true, true)) do
+          if M.path.exists(p) then
+            return path
+          end
         end
+      end)
+
+      if match ~= nil then
+        return match
       end
     end
   end
-  return function(startpath)
-    startpath = M.strip_archive_subpath(startpath)
-    return M.search_ancestors(startpath, matcher)
-  end
 end
 
 function M.find_git_ancestor(startpath)

test/lspconfig_spec.lua

@@ -136,7 +136,7 @@ describe('lspconfig', function()
         -- change the working directory to test directory
         vim.api.nvim_command 'cd ./test/test_dir/a'
         local cwd = vim.fn.getcwd()
-        eq(true, cwd == lspconfig.util.root_pattern { 'root_marker.txt', 'a_marker.txt' }(cwd))
+        eq(true, cwd == lspconfig.util.root_pattern { 'a_marker.txt', 'root_marker.txt' }(cwd))
       end)
 
       it('resolves to root_marker.txt', function()