From 7eeea5be054dd13d83e21761c06249bb2323ef98 Mon Sep 17 00:00:00 2001
From: Marcel Arie <googlillo@gmail.com>
Date: Sun, 19 Dec 2021 14:00:38 +0100
Subject: [PATCH] break: cleanup preview.treesitter language setting

this follows nvim-treesitter more closely but enable can also be a table
of enabled languages

The config now looks like this:
```lua
defaults = {
  preview = {
    treesitter = {
      enable = false,
      -- or
      enable = { "c" },
      -- disable can be set if enable isn't set
      disable = { "perl", "javascript" },
    },
  },
},
```
---
 doc/telescope.txt                  | 13 +++++++++++--
 lua/telescope/config.lua           | 13 +++++++++++--
 lua/telescope/previewers/utils.lua | 26 ++++++++++++++++++++------
 3 files changed, 42 insertions(+), 10 deletions(-)

diff --git a/doc/telescope.txt b/doc/telescope.txt
index 6381b12d23..4a6eb1ad4a 100644
--- a/doc/telescope.txt
+++ b/doc/telescope.txt
@@ -497,8 +497,17 @@ telescope.setup({opts})                                    *telescope.setup()*
                               highlighting, which falls back to regex-based highlighting.
                               `true`: treesitter highlighting for all available filetypes
                               `false`: regex-based highlighting for all filetypes
-                              `table`: table of filetypes for which to attach treesitter
-                              highlighting
+                              `table`: following nvim-treesitters highlighting options:
+                                It contains two keys:
+                                  - enable boolean|table: if boolean, enable all ts
+                                                          highlighing with that flag,
+                                                          disable still considered.
+                                                          Containing a list of filetypes,
+                                                          that are enabled, disabled
+                                                          ignored because it doesnt make
+                                                          any sense in this case.
+                                  - disable table: containing a list of filetypes
+                                                   that are disabled
                               Default: true
           - msg_bg_fillchar:  Character to fill background of unpreviewable buffers with
                               Default: "╱"
diff --git a/lua/telescope/config.lua b/lua/telescope/config.lua
index c5a9ebf4a4..8198ee2b1b 100644
--- a/lua/telescope/config.lua
+++ b/lua/telescope/config.lua
@@ -593,8 +593,17 @@ append(
                           highlighting, which falls back to regex-based highlighting.
                           `true`: treesitter highlighting for all available filetypes
                           `false`: regex-based highlighting for all filetypes
-                          `table`: table of filetypes for which to attach treesitter
-                          highlighting
+                          `table`: following nvim-treesitters highlighting options:
+                            It contains two keys:
+                              - enable boolean|table: if boolean, enable all ts
+                                                      highlighing with that flag,
+                                                      disable still considered.
+                                                      Containing a list of filetypes,
+                                                      that are enabled, disabled
+                                                      ignored because it doesnt make
+                                                      any sense in this case.
+                              - disable table: containing a list of filetypes
+                                               that are disabled
                           Default: true
       - msg_bg_fillchar:  Character to fill background of unpreviewable buffers with
                           Default: "╱"
diff --git a/lua/telescope/previewers/utils.lua b/lua/telescope/previewers/utils.lua
index d250894b5c..b1d1d5ec56 100644
--- a/lua/telescope/previewers/utils.lua
+++ b/lua/telescope/previewers/utils.lua
@@ -82,12 +82,26 @@ end
 utils.highlighter = function(bufnr, ft, opts)
   opts = opts or {}
   opts.preview = opts.preview or {}
-  opts.preview.treesitter = vim.F.if_nil(
-    opts.preview.treesitter,
-    type(conf.preview) == "table" and conf.preview.treesitter
-  )
-  local ts_highlighting = opts.preview.treesitter == true
-    or type(opts.preview.treesitter) == "table" and vim.tbl_contains(opts.preview.treesitter, ft)
+  opts.preview.treesitter = vim.F.if_nil(opts.preview.treesitter, conf.preview.treesitter)
+  if type(opts.preview.treesitter) == "boolean" then
+    local temp = { enable = opts.preview.treesitter }
+    opts.preview.treesitter = temp
+  end
+
+  local ts_highlighting = (function()
+    if type(opts.preview.treesitter.enable) == "table" then
+      if vim.tbl_contains(opts.preview.treesitter.enable, ft) then
+        return true
+      end
+      return false
+    end
+
+    if vim.tbl_contains(vim.F.if_nil(opts.preview.treesitter.disable, {}), ft) then
+      return false
+    end
+
+    return opts.preview.treesitter.enable == nil or opts.preview.treesitter.enable == true
+  end)()
 
   local ts_success
   if ts_highlighting then