Open auth URL automatically in browser on login (#256)

* Open auth URL automatically in browser on login

* Pin older version of open for CJS support

* Vendor openUrl

* Remove open dep

* Wrap in try/catch

* Promisify

src/openUrl.ts

@@ -0,0 +1,41 @@
+import { spawn } from "child_process";
+
+function getCommandForPlatform(): string {
+  switch (process.platform) {
+    case "darwin":
+      return "open";
+    case "win32":
+      return "explorer.exe";
+    case "linux":
+      return "xdg-open";
+    default:
+      return "open";
+  }
+}
+
+export async function openUrl(url: string): Promise<void> {
+  return new Promise((resolve, reject) => {
+    const command = getCommandForPlatform();
+    const child = spawn(command, [url]);
+    let errorText = "";
+
+    child.stderr.setEncoding("utf8");
+
+    child.stderr.on("data", function (data) {
+      errorText += data;
+    });
+
+    child.stderr.on("end", function () {
+      if (errorText.length > 0) {
+        const error = new Error(errorText);
+        reject(error);
+      } else {
+        resolve();
+      }
+    });
+
+    child.on("error", (error) => {
+      reject(error);
+    });
+  });
+}