Add temporary gulp shim for testing

Author: jakebailey

Gulpfile.js

@@ -0,0 +1 @@
+throw new Error("Do not use; run hereby instead.");

package.json

@@ -80,6 +80,7 @@
         "which": "^2.0.2"
     },
     "scripts": {
+        "prepare": "node ./scripts/installGulpShim.mjs",
         "test": "hereby runtests-parallel --light=false",
         "test:eslint-rules": "hereby run-eslint-rules-tests",
         "build": "npm run build:compiler && npm run build:tests",

scripts/installGulpShim.mjs

@@ -0,0 +1,26 @@
+import fs from "fs";
+
+await fs.promises.mkdir("node_modules/gulp", { recursive: true });
+
+await fs.promises.writeFile("node_modules/gulp/package.json", JSON.stringify({
+    name: "gulp",
+    version: "4.0.2",
+    bin: "index.js",
+}));
+
+await fs.promises.writeFile("node_modules/gulp/index.js", `
+const cp = require("child_process");
+const path = require("path");
+const chalk = require("chalk");
+
+console.error(chalk.red("Warning: using gulp shim; please run hereby instead."));
+
+const args = [
+    ...process.execArgv,
+    path.join(__dirname, "..", "hereby", "bin", "hereby.js"),
+    ...process.argv.slice(2),
+];
+
+const { status } = cp.spawnSync(process.execPath, args, { stdio: "inherit" });
+process.exit(status ?? 1);
+`);