From 81daf86b3e8f9254b52b88208421b41f30ab213d Mon Sep 17 00:00:00 2001
From: Thomas Vigouroux <tomvig38@gmail.com>
Date: Mon, 27 Jul 2020 11:41:00 +0200
Subject: [PATCH] wip

---
 lua/nvim-treesitter/highlight.lua     | 16 ++++---
 lua/nvim-treesitter/language_tree.lua | 63 +++++++++++++++++++++++++++
 queries/markdown/injection.scm        |  3 ++
 tests/nvim_treesitter_spec.lua        | 43 ++++++++++++++++++
 4 files changed, 120 insertions(+), 5 deletions(-)
 create mode 100644 lua/nvim-treesitter/language_tree.lua
 create mode 100644 queries/markdown/injection.scm
 create mode 100644 tests/nvim_treesitter_spec.lua

diff --git a/lua/nvim-treesitter/highlight.lua b/lua/nvim-treesitter/highlight.lua
index 867c70caf..756752946 100644
--- a/lua/nvim-treesitter/highlight.lua
+++ b/lua/nvim-treesitter/highlight.lua
@@ -9,7 +9,9 @@ local M = {
   highlighters = {}
 }
 
-local hlmap = vim.treesitter.TSHighlighter.hl_map
+local TSHighlighter = vim.treesitter.TSHighlighter
+
+local hlmap = TSHighlighter.hl_map
 
 -- Misc
 hlmap.error = "TSError"
@@ -52,6 +54,13 @@ hlmap["type.builtin"] = "TSTypeBuiltin"
 hlmap["structure"] = "TSStructure"
 hlmap["include"] = "TSInclude"
 
+function M.create_highlighter(bufnr, lang)
+  local query = queries.get_query(lang, "highlights")
+  if not query then return end
+
+  M.highlighters[bufnr] = ts.TSHighlighter.new(query, bufnr, lang)
+end
+
 function M.attach(bufnr, lang)
   local bufnr = bufnr or api.nvim_get_current_buf()
   local lang = lang or parsers.get_buf_lang(bufnr)
@@ -61,10 +70,7 @@ function M.attach(bufnr, lang)
     hlmap[k] = v
   end
 
-  local query = queries.get_query(lang, "highlights")
-  if not query then return end
-
-  M.highlighters[bufnr] = ts.TSHighlighter.new(query, bufnr, lang)
+  create_highlighter(bufnr, lang)
 end
 
 function M.detach(bufnr)
diff --git a/lua/nvim-treesitter/language_tree.lua b/lua/nvim-treesitter/language_tree.lua
new file mode 100644
index 000000000..d79286114
--- /dev/null
+++ b/lua/nvim-treesitter/language_tree.lua
@@ -0,0 +1,63 @@
+local api = vim.api
+local ts = vim.treesitter
+local parsers = require"nvim-tresitter.parsers"
+local query = require"nvim-treesitter.query"
+local hl = require"nvim-treesitter.highlight"
+
+local ts_hs_ns = api.nvim_get_namespaces()["treesitter_hl"]
+
+local M = {}
+
+local LanguageTree = {}
+
+function LanguageTree.new(bufnr, language, ranges)
+  local buffer = bufnr or api.nvim_get_current_buf()
+  local lang = language or parsers.get_buf_lang(bufnr)
+
+  if ranges then
+    parser.set_included_ranges(ranges)
+  end
+
+  local hl_query = hl.create_highlighter(bufnr, lang)
+  local injection_query = query.get_query(lang, "injections")
+
+  local self = setmetatable({
+    buf = buffer,
+    hl_query = hl_query,
+    injection_query = injection_query,
+    children = {}
+  }, LanguageTree)
+
+  self.parser = ts.get_parser(buffer, lang, {
+    on_changedtree = function(...) self:on_changedtree(...) end
+  })
+
+  return end
+
+function LanguageTree:on_changedtree(changes)
+  -- Get a fresh root
+  if not self.injection_query then return end
+  local root = self.parser.tree:root()
+
+  for _, ch in ipairs(changes or {}) do
+
+    for match in query.iter_prepared_matches(self.injection_query, changed_node, self.buf, ch[1], ch[3] + 1) do
+      if match.content then
+        local start_row, start_col, end_row, end_col = match.content:range()
+        -- TODO(vigoux): this might be quite wrong
+        api.nvim_buf_clear_namespace(self.buf, ts_hs_ns, start_row, end_row)
+
+        -- Language injection here
+        if match.lang then
+
+          -- Prepare the child if not already done
+          if not self.children[match.lang] then
+            self.children[match.lang] = { ranges = {} }
+          end
+        end
+      end
+    end
+  end
+end
+
+return M
diff --git a/queries/markdown/injection.scm b/queries/markdown/injection.scm
new file mode 100644
index 000000000..12d02c34d
--- /dev/null
+++ b/queries/markdown/injection.scm
@@ -0,0 +1,3 @@
+(fenced_code_block
+  (info_string) @injection.lang
+  (code_fence_content) @injection.content)
diff --git a/tests/nvim_treesitter_spec.lua b/tests/nvim_treesitter_spec.lua
new file mode 100644
index 000000000..2fe297108
--- /dev/null
+++ b/tests/nvim_treesitter_spec.lua
@@ -0,0 +1,43 @@
+local helpers = require('test.functional.helpers')(after_each)
+local Screen = require('test.functional.ui.screen')
+local clear, command = helpers.clear, helpers.command
+local feed, alter_slashes = helpers.feed, helpers.alter_slashes
+local insert = helpers.insert
+
+describe('nvim-treesitter', function()
+ local screen
+
+ before_each(function()
+   clear()
+   screen = Screen.new(81, 15)
+   screen:attach()
+ end)
+
+ after_each(function()
+   screen:detach()
+ end)
+
+ it('basically works', function()
+   insert("This is a line")
+
+   screen:expect([[
+  This is a lin^e                                                                   |
+  {2:~                                                                                }|
+  {2:~                                                                                }|
+  {2:~                                                                                }|
+  {2:~                                                                                }|
+  {2:~                                                                                }|
+  {2:~                                                                                }|
+  {2:~                                                                                }|
+  {2:~                                                                                }|
+  {2:~                                                                                }|
+  {2:~                                                                                }|
+  {2:~                                                                                }|
+  {2:~                                                                                }|
+  {2:~                                                                                }|
+                                                                                   |
+]], {[2] = {bold = true, foreground = Screen.colors.Blue1}})
+
+ end)
+
+end)