feat: make the formatter path configurable

README.md

@@ -18,7 +18,7 @@ Adds [nix](https://nixos.org/) language support for VSCode Editor.
 
 * When `Language Server` support is not enabled the following tools are used to
   + Formatting support
-    - with the help of [nixpkgs-format](https://github.com/nix-community/nixpkgs-fmt)
+    - with the help of [nixpkgs-format](https://github.com/nix-community/nixpkgs-fmt) or other tools as specified by the `nix.formatterPath` option
   + Error Report
     - Using `nix-instantiate` errors reported
 

package.json

@@ -70,6 +70,11 @@
     "configuration": {
       "title": "NixIDE",
       "properties": {
+        "nix.formatterPath": {
+          "type": "string",
+          "default": "nixpkgs-fmt",
+          "description": "Location of the nix formatter command."
+        },
         "nix.serverPath": {
           "type": "string",
           "default": "rnix-lsp",

src/configuration.ts

@@ -17,6 +17,10 @@ export class Config {
     return this.cfg.get<T>(path) ?? def_val;
   }
 
+  get formatterPath(): string {
+    return this.get<string>("formatterPath", "nixpkgs-fmt");
+  }
+
   get serverPath(): string {
     return this.get<string>("serverPath", "rnix-lsp");
   }

src/formatter.ts

@@ -7,8 +7,9 @@ import {
   TextEdit,
 } from "vscode";
 import { IProcessResult, runInWorkspace } from "./process-runner";
+import { config } from "./configuration";
 
-const FORMATTER = "nixpkgs-fmt";
+const FORMATTER = config.formatterPath;
 
 /**
  * Get text edits to format a range in a document.
@@ -33,7 +34,9 @@ const getFormatRangeEdits = async (
     );
   } catch (error) {
     if (error instanceof Error) {
-      await vscode.window.showErrorMessage(`Failed to run ${FORMATTER}: ${error.message}`);
+      await vscode.window.showErrorMessage(
+        `Failed to run ${FORMATTER}: ${error.message}`
+      );
     }
     // Re-throw the error to make the promise fail
     throw error;