create snippets in Helix

quantonganh · Jul 31, 2023 · 748d90d · 748d90d
1 parent bfe2116
commit 748d90d
Showing 1 changed file with 139 additions and 0 deletions.
diff --git a/posts/2023/07/31/create-snippets-in-helix.md b/posts/2023/07/31/create-snippets-in-helix.md
@@ -0,0 +1,139 @@
+---
+title: "How to create snippets in Helix?"
+date: 2023-07-31
+description:
+categories:
+- Programming
+tags:
+- helix
+- lsp
+- golang
+---
+[Helix currently does not support snippets](https://github.com/helix-editor/helix/issues/395).
+However, there is a workaround to insert snippets using `:insert-output` to run a shell command.
+Still, this might not feel like the most natural way to work with snippets.
+
+For instance, in GoLand, a similar feature called [live templates](https://www.jetbrains.com/help/go/using-live-templates.html#live_templates_types)
+allows you to type `err` and expand it into the following:
+
+```go
+if err != nil {
+
+}
+```
+
+I wonder if I can archieve the same functionality in Helix by creating a simple language server 
+using the [Language Server Protocol](https://microsoft.github.io/language-server-protocol/).
+
+After exploring different [SDKs for the LSP](https://microsoft.github.io/language-server-protocol/implementors/sdks/) 
+I decided to give [go-lsp](https://github.com/TobiasYin/go-lsp) a try, as I am most familiar with Golang.
+
+Here's what I came up with: https://github.com/quantonganh/snippets-ls.
+
+Initially, I encountered and error during the first attempt:
+
+```json
+{
+  "jsonrpc": "",
+  "id": 0,
+  "result": {
+    "capabilities": {
+      "textDocumentSync": 1,
+      "completionProvider": {
+        "triggerCharacters": [
+          "."
+        ]
+      }
+    }
+  },
+  "error": null
+}
+```
+
+```
+2023-07-31T17:12:56.162 helix_lsp::transport [ERROR] snippets-ls err: <- Parse(Error("data did not match any variant of untagged enum ServerMessage", line: 0, column: 0))
+```
+
+However, I was able to resolve the issue by [passing the jsonrpc version in the response](https://github.com/TobiasYin/go-lsp/pull/6).
+
+To test this feature, you can create a configuration file like this:
+
+```yaml
+main: |-
+  func main() {
+      $1
+  }
+
+err: |-
+  if err != nil {
+      $1
+  }
+```
+
+Then add the following into `~/.config/helix/languages.toml`:
+
+```toml
+[[language]]
+name = "go"
+formatter = { command = "goimports"}
+language-servers = ["gopls", "snippets-ls"]
+
+[language-server.snippets-ls]
+args = ["-config", "/Users/quantong/.config/helix/go-snippets.yaml"]
+command="snippets-ls"
+```
+
+Now, when we open a `.go` file in Helix, the editor forks a process to start the language server:
+
+```sh
+$ pstree -p 818
+-+= 00001 root /sbin/launchd
+ \-+= 00440 quantong /Applications/WezTerm.app/Contents/MacOS/wezterm-gui
+   \-+= 00487 quantong -fish
+     \-+= 00818 quantong hx .
+       |--- 00855 quantong /opt/homebrew/bin/gopls
+       \--- 00856 quantong /Users/quantong/go/bin/snippets-ls -config /Users/quantong/.config/helix/go-snippets.yaml
+```
+
+Next, you can type `err` and press tab, Helix will send a `textDocument/completion` request to the language server:
+
+```json
+{
+  "jsonrpc": "2.0",
+  "method": "textDocument/completion",
+  "params": {
+    "position": {
+      "character": 2,
+      "line": 25
+    },
+    "textDocument": {
+      "uri": "file:///Users/quantong/Code/personal/snippets-ls/main.go"
+    }
+  },
+  "id": 3
+}
+```
+
+and the server will respond with the result:
+
+```json
+{
+  "jsonrpc": "2.0",
+  "id": 3,
+  "result": [
+    {
+      "label": "main",
+      "kind": 15,
+      "insertText": "func main() {\n    $1\n}"
+    },
+    {
+      "label": "err",
+      "kind": 15,
+      "insertText": "if err != nil {\n    $1\n}"
+    }
+  ],
+  "error": null
+}
+```
+
+With this setup, you should be able to use snippets in Helix just like in GoLand, enhancing your coding productivity.