feat: Allow specifying a subdirectory in which to start Lexical (#66)

* Add config to start Lexical in workspace sub-directory

* extract config helper

* add configuration tests

* update changelog

CHANGELOG.md

@@ -8,6 +8,8 @@
   if it isn't already running. Useful to quickly restart Lexical if initial
   start failed due to environment reasons, like an incompatible version of
   Erlang or Elixir.
+- Added the `projectDir` configuration option which lets users specify a
+  subdirectory in which Lexical should be started instead of the workspace root.
 
 ### Documentation
 

package.json

@@ -121,6 +121,11 @@
           "scope": "window",
           "type": "string",
           "markdownDescription": "The path to the lexical executable. The path should point to a folder containing the `start_lexical.sh` or an executable file. Note that setting this to any value will disable automatic installation of Lexical."
+        },
+        "lexical.server.projectDir": {
+          "scope": "window",
+          "type": "string",
+          "markdownDescription": "A subdirectory of the current workspace in which to start Lexical."
         }
       }
     },

src/configuration.ts

@@ -1,10 +1,31 @@
-import { workspace } from "vscode";
+import path = require("path");
+import type { workspace as vsWorkspace } from "vscode";
+import { URI } from "vscode-uri";
 
 namespace Configuration {
-	export function getReleasePathOverride(): string | undefined {
-		return workspace
-			.getConfiguration("lexical.server")
-			.get("releasePathOverride");
+	type GetConfig = (section: string) => unknown;
+
+	export function getReleasePathOverride(
+		getConfig: GetConfig
+	): string | undefined {
+		return getConfig("releasePathOverride") as string | undefined;
+	}
+
+	export function getProjectDirUri(
+		getConfig: GetConfig,
+		workspace: typeof vsWorkspace
+	): URI {
+		const projectDirConfig = getConfig("projectDir");
+
+		// eslint-disable-next-line @typescript-eslint/no-non-null-assertion
+		const workspacePath = workspace.workspaceFolders![0].uri.path;
+
+		if (typeof projectDirConfig === "string") {
+			const fullDirectoryPath = path.join(workspacePath, projectDirConfig);
+			return URI.file(fullDirectoryPath);
+		} else {
+			return URI.file(workspacePath);
+		}
 	}
 }
 

src/extension.ts

@@ -1,6 +1,6 @@
 // The module 'vscode' contains the VS Code extensibility API
 // Import the module and reference it with the alias vscode in your code below
-import { ExtensionContext, commands, window } from "vscode";
+import { ExtensionContext, commands, window, workspace } from "vscode";
 import LanguageServer from "./language-server";
 import Configuration from "./configuration";
 import {
@@ -12,14 +12,16 @@ import { join } from "path";
 import * as fs from "fs";
 import Commands from "./commands";
 import restartServer from "./commands/restart-server";
+import { URI } from "vscode-uri";
 
 // This method is called when your extension is activated
 // Your extension is activated the very first time the command is executed
 export async function activate(context: ExtensionContext): Promise<void> {
 	const startScriptOrReleaseFolderPath = await maybeAutoInstall(context);
+	const projectDir = Configuration.getProjectDirUri(getConfig, workspace);
 
 	if (startScriptOrReleaseFolderPath !== undefined) {
-		const client = await start(startScriptOrReleaseFolderPath);
+		const client = await start(startScriptOrReleaseFolderPath, projectDir);
 
 		const registerCommand = Commands.getRegisterFunction((id, handler) => {
 			context.subscriptions.push(commands.registerCommand(id, handler));
@@ -38,7 +40,7 @@ export function deactivate(): void {}
 async function maybeAutoInstall(
 	context: ExtensionContext
 ): Promise<string | undefined> {
-	const releasePathOverride = Configuration.getReleasePathOverride();
+	const releasePathOverride = Configuration.getReleasePathOverride(getConfig);
 
 	if (releasePathOverride !== undefined && releasePathOverride !== "") {
 		console.log(
@@ -69,9 +71,15 @@ function isExecutableFile(path: fs.PathLike): boolean {
 }
 
 async function start(
-	startScriptOrReleaseFolderPath: string
+	startScriptOrReleaseFolderPath: string,
+	workspaceUri: URI
 ): Promise<LanguageClient> {
 	const outputChannel = window.createOutputChannel("Lexical");
+
+	outputChannel.appendLine(
+		`Starting Lexical in directory ${workspaceUri?.fsPath}`
+	);
+
 	const startScriptPath = isExecutableFile(startScriptOrReleaseFolderPath)
 		? startScriptOrReleaseFolderPath
 		: join(startScriptOrReleaseFolderPath, "start_lexical.sh");
@@ -94,6 +102,11 @@ async function start(
 			{ language: "phoenix-heex", scheme: "file" },
 			{ language: "phoenix-heex", scheme: "untitled" },
 		],
+		workspaceFolder: {
+			index: 0,
+			uri: workspaceUri,
+			name: workspaceUri.path,
+		},
 	};
 
 	const client = new LanguageClient(
@@ -115,3 +128,7 @@ async function start(
 
 	return client;
 }
+
+function getConfig(section: string) {
+	return workspace.getConfiguration("lexical.server").get(section);
+}

src/test/configuration.test.ts

@@ -0,0 +1,30 @@
+import { describe, test, jest, expect } from "@jest/globals";
+import Configuration from "../configuration";
+import { URI } from "vscode-uri";
+import WorkspaceFixture from "./fixtures/workspace-fixture";
+
+describe("Configuration", () => {
+	test("getProjectDirUri returns the workspace URI when project dir is not configured", () => {
+		const getConfigMock = jest.fn().mockReturnValue(undefined);
+		const workspace = WorkspaceFixture.withUri(URI.file("/stub"));
+		const projectDirUri = Configuration.getProjectDirUri(
+			getConfigMock,
+			workspace
+		);
+
+		// eslint-disable-next-line @typescript-eslint/no-non-null-assertion
+		expect(projectDirUri).toEqual(workspace.workspaceFolders![0].uri);
+	});
+
+	test("getProjectDirUri returns the full directory URI when project dir is configured", () => {
+		const getConfigMock = jest.fn().mockReturnValue("subdirectory");
+		const workspace = WorkspaceFixture.withUri(URI.file("/stub"));
+		const projectDirUri = Configuration.getProjectDirUri(
+			getConfigMock,
+			workspace
+		);
+
+		// eslint-disable-next-line @typescript-eslint/no-non-null-assertion
+		expect(projectDirUri).toEqual(URI.file("/stub/subdirectory"));
+	});
+});

src/test/fixtures/workspace-fixture.ts

@@ -0,0 +1,13 @@
+import { URI } from "vscode-uri";
+
+import type { workspace as vsWorkspace } from "vscode";
+
+namespace WorkspaceFixture {
+	export function withUri(uri: URI): typeof vsWorkspace {
+		return {
+			workspaceFolders: [{ uri }],
+		} as unknown as typeof vsWorkspace;
+	}
+}
+
+export default WorkspaceFixture;