c# not work

[CRAG666]

A few days ago I could use it with C# but after updating it doesn't work it tells me that "Language cs not supported."

[danymat]

Hmm, weird
It should have said csharp instead..
Can you go on a csharp file and print :lua print(vim.no.filetype) ?

[danymat]

Hello, indeed the new Neogen internals require the filename to be exactly the result of filetype, can you try it out ?

[MikaelElkiaer]

@danymat Late ping, sorry, was unsure whether this would go unnoticed as the issue is closed.

There seems to be another problem related to this.

I get the following error with the latest version:

E5108: Error executing lua /usr/share/nvim/runtime/lua/vim/treesitter/language.lua:25: no parser for 'cs' language, see :help treesitter-parsers
stack traceback:
        [C]: in function 'error'
        /usr/share/nvim/runtime/lua/vim/treesitter/language.lua:25: in function 'require_language'
        /usr/share/nvim/runtime/lua/vim/treesitter.lua:39: in function '_create_parser'
        /usr/share/nvim/runtime/lua/vim/treesitter.lua:94: in function 'get_parser'
        ...m/site/pack/packer/start/neogen/lua/neogen/generator.lua:41: in function 'get_parent_node'
        ...m/site/pack/packer/start/neogen/lua/neogen/generator.lua:206: in function 'generate'
        [string ":lua"]:1: in main chunk

So it correctly finds a configuration based on the cs filetype. But it directly uses that to look up the TreeSitter parser - which is called c_sharp.
Perhaps something has changed with vim.treesitter.get_parser as used here:

neogen/lua/neogen/generator.lua

Line 41 in f249a70

local parser = vim.treesitter.get_parser(0, filetype)

Trying it out with lua print(vim.treesitter.get_parser(0, "c_sharp")) I get a result, but not for lua print(vim.treesitter.get_parser(0, "cs")).

[danymat]

Hello, can you try again with latest commit ? 32adfde

[MikaelElkiaer]

Hello, can you try again with latest commit ? 32adfde

I did try renaming myself, but it only moved the problem, as it then cannot match the filetype with a neogen configuration:

E5108: Error executing lua ...m/site/pack/packer/start/neogen/lua/neogen/generator.lua:201: attempt to index field 'parent' (a nil value)
stack traceback:
        ...m/site/pack/packer/start/neogen/lua/neogen/generator.lua:201: in function 'generate'
        [string ":lua"]:1: in main chunk

So, nvim filetype is cs, while treesitter parser filetype is c_sharp.

It works if I keep the keep the file named lua/neogen/configurations/cs.lua and then do a simple mapping before getting the parser:

diff --git a/lua/neogen/generator.lua b/lua/neogen/generator.lua
index b762176..a4f2cc8 100644
--- a/lua/neogen/generator.lua
+++ b/lua/neogen/generator.lua
@@ -38,7 +38,8 @@ local function todo_text(type)
 end

 local function get_parent_node(filetype, typ, language)
-    local parser = vim.treesitter.get_parser(0, filetype)
+    local parser_name = filetype == "cs" and "c_sharp" or filetype
+    local parser = vim.treesitter.get_parser(0, parser_name)
     local tstree = parser:parse()[1]
     local tree = tstree:root()

I do wonder how this worked earlier. Perhaps vim.treesitter.get_parser has changed? It is a little unclear that its parameter filetype refers to a name known to treesitter which does not necessarily correspond to the nvim filenameg.

[danymat]

Very weird, nvim-treesitter has likely changed the name in fact.
Do you want to create a PR for that (revert the file change, and apply the patch) ? I'm not at home at the moment, so i can not do it for the next hours

[MikaelElkiaer]

Very weird, nvim-treesitter has likely changed the name in fact. Do you want to create a PR for that (revert the file change, and apply the patch) ? I'm not at home at the moment, so i can not do it for the next hours

I'm using the patch locally for now, so no rush. I might do a PR if I can come up with a bit more generic way of handling the mapping from filetype to treesitters parser name.

[MikaelElkiaer]

@danymat I found out how to do the mapping and added a PR #89.