feat: main two places, process.env.GH_TOKEN and gh auth token

README.md

@@ -22,11 +22,22 @@ npm i get-github-auth-token
 ```
 
 ```ts
-import { greet } from "get-github-auth-token";
+import { getGitHubAuthToken } from "get-github-auth-token";
 
-greet("Hello, world! 💖");
+const auth = await getGitHubAuthToken("Hello, world! 💖");
+
+if (auth.succeeded) {
+	console.log("Token:", auth.token);
+} else {
+	console.error("Oh no:", auth.error);
+}
 ```
 
+`getGitHubAuthToken` attempts to find a GitHub auth token from the following places, in order:
+
+1. `process.env.GH_TOKEN`
+2. Executing `gh auth token` as a child process
+
 ## Contributors
 
 <!-- spellchecker: disable -->

eslint.config.js

@@ -70,6 +70,12 @@ export default tseslint.config(
 
 			// These on-by-default rules work well for this repo if configured
 			"@typescript-eslint/no-unused-vars": ["error", { caughtErrors: "all" }],
+			"@typescript-eslint/prefer-nullish-coalescing": [
+				"error",
+				{
+					ignorePrimitives: { string: true },
+				},
+			],
 			"perfectionist/sort-objects": [
 				"error",
 				{

package.json

@@ -38,6 +38,7 @@
 		"@eslint/js": "9.3.0",
 		"@release-it/conventional-changelog": "8.0.1",
 		"@types/eslint-plugin-markdown": "2.0.2",
+		"@types/node": "^20.12.12",
 		"@vitest/coverage-v8": "1.6.0",
 		"console-fail-test": "0.2.3",
 		"cspell": "8.8.3",

src/getGitHubAuthToken.test.ts

@@ -0,0 +1,78 @@
+import { beforeEach, describe, expect, it, vi } from "vitest";
+
+import { getGitHubAuthToken } from "./getGitHubAuthToken.js";
+
+const mockExec = vi.fn();
+
+vi.mock("node:util", () => ({
+	get promisify() {
+		return () => mockExec;
+	},
+}));
+
+describe("getGitHubAuthToken", () => {
+	beforeEach(() => {
+		process.env.GH_TOKEN = "";
+	});
+
+	it("returns GH_TOKEN when it exists and is truthy", async () => {
+		const GH_TOKEN = "gho_abc123";
+
+		process.env.GH_TOKEN = GH_TOKEN;
+
+		const actual = await getGitHubAuthToken();
+
+		expect(actual).toEqual({ succeeded: true, token: GH_TOKEN });
+		expect(mockExec).not.toHaveBeenCalled();
+	});
+
+	it("returns the token when gh auth token prints a token", async () => {
+		const stdout = "gho_abc123";
+
+		mockExec.mockResolvedValue({ stdout });
+
+		const actual = await getGitHubAuthToken();
+
+		expect(actual).toEqual({ succeeded: true, token: stdout });
+	});
+
+	it("returns the gh error when gh auth token and gh error", async () => {
+		const stderr = "Oh no!";
+
+		mockExec.mockResolvedValueOnce({ stderr: "auth token issue" });
+		mockExec.mockResolvedValueOnce({ stderr });
+
+		const actual = await getGitHubAuthToken();
+
+		expect(actual).toEqual({
+			error: `Could not run \`gh\`: ${stderr}`,
+			succeeded: false,
+		});
+	});
+
+	it("returns the gh auth token error when only gh auth token errors", async () => {
+		const stderr = "Oh no!";
+
+		mockExec.mockResolvedValueOnce({ stderr });
+		mockExec.mockResolvedValueOnce({ stdout: "" });
+
+		const actual = await getGitHubAuthToken();
+
+		expect(actual).toEqual({
+			error: stderr,
+			succeeded: false,
+		});
+	});
+
+	it("returns undefined when both gh and gh auth token print nothing", async () => {
+		mockExec.mockResolvedValueOnce({ stderr: "", stdout: "" });
+		mockExec.mockResolvedValueOnce({ stderr: "", stdout: "" });
+
+		const actual = await getGitHubAuthToken();
+
+		expect(actual).toEqual({
+			error: undefined,
+			succeeded: false,
+		});
+	});
+});

src/getGitHubAuthToken.ts

@@ -0,0 +1,27 @@
+import * as cp from "node:child_process";
+import * as util from "node:util";
+
+import { GitHubAuthToken } from "./types.js";
+
+export async function getGitHubAuthToken(): Promise<GitHubAuthToken> {
+	if (process.env.GH_TOKEN) {
+		return { succeeded: true, token: process.env.GH_TOKEN };
+	}
+
+	const exec = util.promisify(cp.exec);
+	const token = await exec("gh auth token");
+
+	if (token?.stdout) {
+		return { succeeded: true, token: token.stdout };
+	}
+
+	const help = await exec("gh");
+
+	return {
+		error:
+			(help.stderr && `Could not run \`gh\`: ${help.stderr}`) ||
+			token?.stderr ||
+			undefined,
+		succeeded: false,
+	};
+}

src/index.ts

@@ -1,2 +1,2 @@
-export * from "./greet.js";
+export * from "./getGitHubAuthToken.js";
 export * from "./types.js";

src/types.ts

@@ -1,5 +1,11 @@
-export interface GreetOptions {
-	logger?: (message: string) => void;
-	message: string;
-	times?: number;
+export interface GitHubAuthTokenFailure {
+	error: string | undefined;
+	succeeded: false;
 }
+
+export interface GitHubAuthTokenSuccess {
+	succeeded: true;
+	token: string;
+}
+
+export type GitHubAuthToken = GitHubAuthTokenFailure | GitHubAuthTokenSuccess;