fix(configs): eliminate some usages of root_pattern #3820

Problem:
`root_pattern` is not necessary for non-glob patterns.

Solution:
Replace non-glob cases with `vim.fs.root()`..

9 files changed, 22 insertions, 34 deletions

diff --git a/lsp/elmls.lua b/lsp/elmls.lua
index bee05b89..a7f27789 100644
--- a/lsp/elmls.lua
+++ b/lsp/elmls.lua
@@ -7,11 +7,8 @@
 --- npm install -g elm elm-test elm-format @elm-tooling/elm-language-server
 --- ```
 
-local util = require 'lspconfig.util'
 local api = vim.api
 
-local elm_root_pattern = util.root_pattern 'elm.json'
-
 return {
   cmd = { 'elm-language-server' },
   -- TODO(ashkan) if we comment this out, it will allow elmls to operate on elm.json. It seems like it could do that, but no other editor allows it right now.
@@ -20,7 +17,7 @@ return {
     local fname = api.nvim_buf_get_name(bufnr)
     local filetype = api.nvim_buf_get_option(0, 'filetype')
     if filetype == 'elm' or (filetype == 'json' and fname:match 'elm%.json$') then
-      on_dir(elm_root_pattern(fname))
+      on_dir(vim.fs.root(fname, 'elm.json'))
       return
     end
     on_dir(nil)
diff --git a/lsp/intelephense.lua b/lsp/intelephense.lua
index bf03985d..b18736a9 100644
--- a/lsp/intelephense.lua
+++ b/lsp/intelephense.lua
@@ -25,17 +25,15 @@
 --- }
 --- ```
 
-local util = require 'lspconfig.util'
-
 return {
   cmd = { 'intelephense', '--stdio' },
   filetypes = { 'php' },
   root_dir = function(bufnr, on_dir)
     local fname = vim.api.nvim_buf_get_name(bufnr)
     local cwd = assert(vim.uv.cwd())
-    local root = util.root_pattern('composer.json', '.git')(fname)
+    local root = vim.fs.root(fname, { 'composer.json', '.git' })
 
     -- prefer cwd if root is a descendant
-    on_dir(vim.fs.relpath(cwd, root) and cwd or root)
+    on_dir(root and vim.fs.relpath(cwd, root) and cwd)
   end,
 }
diff --git a/lsp/kotlin_language_server.lua b/lsp/kotlin_language_server.lua
index 661822e5..d70afa78 100644
--- a/lsp/kotlin_language_server.lua
+++ b/lsp/kotlin_language_server.lua
@@ -16,10 +16,6 @@
 --- For faster startup, you can setup caching by specifying a storagePath
 --- in the init_options. The default is your home directory.
 
-local util = require 'lspconfig.util'
-
-local bin_name = 'kotlin-language-server'
-
 --- The presence of one of these files indicates a project root directory
 --
 --  These are configuration files for the various build systems supported by
@@ -37,9 +33,9 @@ local root_files = {
 return {
   filetypes = { 'kotlin' },
   root_markers = root_files,
-  cmd = { bin_name }, -- kotlin-language-server
+  cmd = { 'kotlin-language-server' },
   init_options = {
     -- Enables caching and use project root to store cache data.
-    storagePath = util.root_pattern(unpack(root_files))(vim.fn.expand '%:p:h'),
+    storagePath = vim.fs.root(vim.fn.expand '%:p:h', root_files),
   },
 }
diff --git a/lsp/lean3ls.lua b/lsp/lean3ls.lua
index 977e04b9..07ff0599 100644
--- a/lsp/lean3ls.lua
+++ b/lsp/lean3ls.lua
@@ -14,8 +14,6 @@
 --- that plugin fully handles the setup of the Lean language server,
 --- and you shouldn't set up `lean3ls` both with it and `lspconfig`.
 
-local util = require 'lspconfig.util'
-
 return {
   cmd = { 'lean-language-server', '--stdio', '--', '-M', '4096', '-T', '100000' },
   filetypes = { 'lean3' },
@@ -33,8 +31,7 @@ return {
     end
 
     on_dir(
-      util.root_pattern 'leanpkg.toml'(fname)
-        or util.root_pattern 'leanpkg.path'(fname)
+      vim.fs.root(fname, { 'leanpkg.toml', 'leanpkg.path' })
         or stdlib_dir
         or vim.fs.dirname(vim.fs.find('.git', { path = fname, upward = true })[1])
     )
diff --git a/lsp/phan.lua b/lsp/phan.lua
index c001f39c..50b0a78a 100644
--- a/lsp/phan.lua
+++ b/lsp/phan.lua
@@ -4,8 +4,6 @@
 ---
 --- Installation: https://github.com/phan/phan#getting-started
 
-local util = require 'lspconfig.util'
-
 local cmd = {
   'phan',
   '-m',
@@ -25,9 +23,9 @@ return {
   root_dir = function(bufnr, on_dir)
     local fname = vim.api.nvim_buf_get_name(bufnr)
     local cwd = assert(vim.uv.cwd())
-    local root = util.root_pattern('composer.json', '.git')(fname)
+    local root = vim.fs.root(fname, { 'composer.json', '.git' })
 
     -- prefer cwd if root is a descendant
-    on_dir(vim.fs.relpath(cwd, root) and cwd or root)
+    on_dir(root and vim.fs.relpath(cwd, root) and cwd)
   end,
 }
diff --git a/lsp/phpactor.lua b/lsp/phpactor.lua
index 87e6c59d..9b7d3d82 100644
--- a/lsp/phpactor.lua
+++ b/lsp/phpactor.lua