feat: allow rules to be treesitter context aware (#423) (#424)

* feat: allow rules to be treesitter context aware

When a rule is defined with the `:with_context()` method, has a
specified filetype, and is operating in a buffer with a treesitter
parser attached, the rule will only execute iff the treesitter language
at the cursor matches one of the filetypes specified in the initial rule
definition.

> If there are no specified filetypes, of there is no parser attached to
> the current buffer, the rule executes as normal

* Add tests for treesitter context in markdown sample

- Add 'ts_context markdown `*` success md_context'
- Add 'ts_context codeblock `*` fail js_context'

lua/nvim-autopairs/ts-conds.lua

@@ -147,4 +147,14 @@ conds.is_not_ts_node_comment = function()
     end
 end
 
+conds.is_not_in_context = function()
+    return function(opts)
+        local context = require("nvim-autopairs.ts-utils")
+            .get_language_tree_at_position({ utils.get_cursor() })
+        if not vim.tbl_contains(opts.rule.filetypes, context:lang()) then
+            return false
+        end
+    end
+end
+
 return conds

lua/nvim-autopairs/ts-utils.lua

@@ -1,6 +1,18 @@
 local ts_get_node_text = vim.treesitter.get_node_text or vim.treesitter.query.get_node_text
 local M = {}
 
+--- Returns the language tree at the given position.
+---@return LanguageTree
+function M.get_language_tree_at_position(position)
+    local language_tree = vim.treesitter.get_parser()
+    language_tree:for_each_tree(function(_, tree)
+        if tree:contains(vim.tbl_flatten({ position, position })) then
+            language_tree = tree
+        end
+    end)
+    return language_tree
+end
+
 function M.get_tag_name(node)
   local tag_name = nil
   if node ~=nil then

tests/endwise/sample.md

@@ -0,0 +1,9 @@
+# Example Markdown File
+
+```javascript
+let;
+let;
+let;
+let;
+let;
+```

tests/test_utils.lua

@@ -133,6 +133,10 @@ _G.Test_withfile = function(test_data, cb)
                     vim.bo.filetype = value.filetype
                 end
             end
+            local status, parser = pcall(vim.treesitter.get_parser, 0)
+            if status then
+                parser:parse(true)
+            end
             vim.api.nvim_buf_set_lines(
                 0,
                 value.linenr - 1,

tests/treesitter_spec.lua

@@ -13,7 +13,7 @@ vim.api.nvim_set_keymap(
 )
 
 ts.setup({
-    ensure_installed = { 'lua', 'javascript', 'rust' },
+    ensure_installed = { 'lua', 'javascript', 'rust', 'markdown', 'markdown_inline' },
     highlight = { enable = true },
     autopairs = { enable = true },
 })
@@ -93,6 +93,36 @@ local data = {
         before = [[pub fn noop(_inp: Vec|) {]],
         after = [[pub fn noop(_inp: Vec<|>) {]],
     },
+    {
+        setup_func = function()
+            npairs.add_rules({
+                Rule('*', '*', { 'markdown', 'markdown_inline' })
+                    :with_pair(ts_conds.is_not_in_context()),
+            })
+        end,
+        name = 'ts_context markdown `*` success md_context',
+        filepath = './tests/endwise/sample.md',
+        linenr = 2,
+        filetype = 'markdown',
+        key = '*',
+        before = [[|]],
+        after = [[*|*]],
+    },
+    {
+        setup_func = function()
+            npairs.add_rules({
+                Rule('*', '*', { 'markdown', 'markdown_inline' })
+                    :with_pair(ts_conds.is_not_in_context()),
+            })
+        end,
+        name = 'ts_context codeblock `*` fail js_context',
+        filepath = './tests/endwise/sample.md',
+        linenr = 6,
+        filetype = 'markdown',
+        key = '*',
+        before = [[let calc = 1  |]],
+        after = [[let calc = 1 *|]],
+    },
 }
 
 local run_data = _G.Test_filter(data)