Bring back VS Code extension from before #85

.gitignore

@@ -1,5 +1,7 @@
 .DS_Store
 *.tgz
+*.vsix
 /packages/core/README.md
+/packages/vscode/*.png
 dist/
 node_modules/

CONTRIBUTING.md

@@ -77,6 +77,18 @@ Or, if you want to host on your local network, e.g. to test on your phone:
 make site-deps && npm run --workspace=@rose-lang/site dev -- --host
 ```
 
+## VS Code
+
+The VS Code extension is built as part of `make` or `make all`, but you can also
+just build it by itself:
+
+```sh
+make vscode
+```
+
+Then `packages/vscode` will contain a `*.vsix` file that you can install in VS
+Code by right-clicking it and clicking the **Install Extension VSIX** button.
+
 [git]: https://git-scm.com/downloads
 [make]: https://en.wikipedia.org/wiki/Make_(software)
 [node]: https://nodejs.org/en/download

Makefile

@@ -23,7 +23,7 @@ prettier: npm
 	npx prettier --check .
 
 # build `packages/`
-packages: core site
+packages: core site vscode
 
 # run JavaScript tests
 test-js: test-core test-site
@@ -50,3 +50,17 @@ site: site-deps
 # test
 test-site: site-deps
 	npm run --workspace=@rose-lang/site test -- run --no-threads
+
+## `packages/vscode`
+
+# fetch encircled icon
+packages/vscode/encircled-rose.png:
+	node fetch.js https://github.com/rose-lang/rose-icons/raw/efcc218832d65970a47bed597ee11cecd3d1cc3c/png/encircled-rose.png $@
+
+# fetch plain icon
+packages/vscode/plain-rose.png:
+	node fetch.js https://github.com/rose-lang/rose-icons/raw/efcc218832d65970a47bed597ee11cecd3d1cc3c/png/plain-rose.png $@
+
+# build
+vscode: npm packages/vscode/encircled-rose.png packages/vscode/plain-rose.png
+	npm run --workspace=rose-vscode build

fetch.js

@@ -0,0 +1,5 @@
+import * as fs from "fs/promises";
+import fetch from "node-fetch";
+
+const [url, path] = process.argv.slice(2);
+await fs.writeFile(path, Buffer.from(await (await fetch(url)).arrayBuffer()));