From afcf64479c1aa5ea53286853370082507f2721f7 Mon Sep 17 00:00:00 2001
From: kevinhwang91 <kevin.hwang@live.com>
Date: Fri, 11 Feb 2022 14:42:23 +0800
Subject: fix(query.lua): check empty table for lines

The range of node may make `nvim_buf_get_lines` return an empty table.
---
 runtime/lua/vim/treesitter/query.lua | 12 +++++++-----
 1 file changed, 7 insertions(+), 5 deletions(-)

diff --git a/runtime/lua/vim/treesitter/query.lua b/runtime/lua/vim/treesitter/query.lua
index b3036ea679..14940332d6 100644
--- a/runtime/lua/vim/treesitter/query.lua
+++ b/runtime/lua/vim/treesitter/query.lua
@@ -199,11 +199,13 @@ function M.get_node_text(node, source)
       lines = a.nvim_buf_get_lines(source, start_row, end_row + 1, true)
     end
 
-    if #lines == 1 then
-      lines[1]      = string.sub(lines[1], start_col+1, end_col)
-    else
-      lines[1]      = string.sub(lines[1], start_col+1)
-      lines[#lines] = string.sub(lines[#lines], 1, end_col)
+    if #lines > 0 then
+      if #lines == 1 then
+        lines[1]      = string.sub(lines[1], start_col+1, end_col)
+      else
+        lines[1]      = string.sub(lines[1], start_col+1)
+        lines[#lines] = string.sub(lines[#lines], 1, end_col)
+      end
     end
 
     return table.concat(lines, "\n")
-- 
cgit 


From 58d81efcb271b93d2d4903d235eab6c97a6c4d39 Mon Sep 17 00:00:00 2001
From: kevinhwang91 <kevin.hwang@live.com>
Date: Fri, 11 Feb 2022 20:59:47 +0800
Subject: fix: append test for checking zero width node range

---
 test/functional/treesitter/parser_spec.lua | 19 +++++++++++++++++++
 1 file changed, 19 insertions(+)

diff --git a/test/functional/treesitter/parser_spec.lua b/test/functional/treesitter/parser_spec.lua
index 396fe5feab..599c74102c 100644
--- a/test/functional/treesitter/parser_spec.lua
+++ b/test/functional/treesitter/parser_spec.lua
@@ -285,6 +285,25 @@ end]]
     eq(true, result)
   end)
 
+  it('support getting empty text if node range is zero width', function()
+    local text = [[
+```lua
+{}
+```]]
+    insert(text)
+    local result = exec_lua([[
+      local fake_node = {}
+      function fake_node:start()
+        return 1, 0, 7
+      end
+      function fake_node:end_()
+        return 1, 0, 7
+      end
+      return vim.treesitter.get_node_text(fake_node, 0) == ''
+    ]])
+    eq(true, result)
+  end)
+
   it('can match special regex characters like \\ * + ( with `vim-match?`', function()
     insert('char* astring = "\\n"; (1 + 1) * 2 != 2;')
 
-- 
cgit