Add preview mode (#399)

Co-authored-by: Itai Steinherz <itaisteinherz@gmail.com>
Co-authored-by: Sindre Sorhus <sindresorhus@gmail.com>

readme.md

@@ -35,6 +35,7 @@
   <sub>(does not apply to external registries)</sub>
 - Opens a prefilled GitHub Releases draft after publish
 - Warns about the possibility of extraneous files being published
+- See exactly what will be executed with [preview mode](https://github.com/sindresorhus/np/issues/391), without pushing or publishing anything remotely
 - Supports [GitHub Packages](https://github.com/features/packages)
 
 
@@ -69,6 +70,7 @@ $ np --help
     --no-tests          Skips tests
     --yolo              Skips cleanup and testing
     --no-publish        Skips publishing
+    --preview           Show tasks without actually executing them
     --tag               Publish under a given dist-tag
     --no-yarn           Don't use Yarn
     --contents          Subdirectory to publish
@@ -101,6 +103,7 @@ Currently, these are the flags you can configure:
 - `tests` - Run `npm test` (`true` by default).
 - `yolo` - Skip cleanup and testing (`false` by default).
 - `publish` - Publish (`true` by default).
+- `preview` - Show tasks without actually executing them (`false` by default).
 - `tag` - Publish under a given dist-tag (`latest` by default).
 - `yarn` - Use yarn if possible (`true` by default).
 - `contents` - Subdirectory to publish (`.` by default).

source/cli.js

@@ -26,6 +26,7 @@ const cli = meow(`
 	  --no-tests          Skips tests
 	  --yolo              Skips cleanup and testing
 	  --no-publish        Skips publishing
+	  --preview           Show tasks without actually executing them
 	  --tag               Publish under a given dist-tag
 	  --no-yarn           Don't use Yarn
 	  --contents          Subdirectory to publish
@@ -67,6 +68,9 @@ const cli = meow(`
 		},
 		contents: {
 			type: 'string'
+		},
+		preview: {
+			type: 'boolean'
 		}
 	}
 });
@@ -103,6 +107,11 @@ updateNotifier({pkg: cli.pkg}).notify();
 
 	console.log(); // Prints a newline for readability
 	const newPkg = await np(options.version, options);
+
+	if (options.preview) {
+		return;
+	}
+
 	console.log(`\n ${newPkg.name} ${newPkg.version} published 🎉`);
 })().catch(error => {
 	console.error(`\n${logSymbols.error} ${error.message}`);

source/index.js

@@ -88,7 +88,9 @@ module.exports = async (input = 'patch', options) => {
 
 	// The default parameter is a workaround for https://github.com/Tapppi/async-exit-hook/issues/9
 	exitHook((callback = () => {}) => {
-		if (publishStatus === 'FAILED') {
+		if (options.preview) {
+			callback();
+		} else if (publishStatus === 'FAILED') {
 			(async () => {
 				await rollback();
 				callback();
@@ -173,11 +175,21 @@ module.exports = async (input = 'patch', options) => {
 		{
 			title: 'Bumping version using Yarn',
 			enabled: () => options.yarn === true,
+			skip: () => {
+				if (options.preview) {
+					return `[Preview] Command not executed: yarn version --new-version ${input}.`;
+				}
+			},
 			task: () => exec('yarn', ['version', '--new-version', input])
 		},
 		{
 			title: 'Bumping version using npm',
 			enabled: () => options.yarn === false,
+			skip: () => {
+				if (options.preview) {
+					return `[Preview] Command not executed: npm version ${input}.`;
+				}
+			},
 			task: () => exec('npm', ['version', input])
 		}
 	]);
@@ -186,6 +198,12 @@ module.exports = async (input = 'patch', options) => {
 		tasks.add([
 			{
 				title: `Publishing package using ${pkgManagerName}`,
+				skip: () => {
+					if (options.preview) {
+						const args = publish.getPackagePublishArguments(options);
+						return `[Preview] Command not executed: ${pkgManager} ${args.join(' ')}.`;
+					}
+				},
 				task: (context, task) => {
 					let hasError = false;
 
@@ -209,6 +227,12 @@ module.exports = async (input = 'patch', options) => {
 			tasks.add([
 				{
 					title: 'Enabling two-factor authentication',
+					skip: () => {
+						if (options.preview) {
+							const args = enable2fa.getEnable2faArgs(pkg.name, options);
+							return `[Preview] Command not executed: npm ${args.join(' ')}.`;
+						}
+					},
 					task: (context, task) => enable2fa(task, pkg.name, {otp: context.otp})
 				}
 			]);
@@ -224,6 +248,10 @@ module.exports = async (input = 'patch', options) => {
 				return 'Upstream branch not found; not pushing.';
 			}
 
+			if (options.preview) {
+				return '[Preview] Command not executed: git push --follow-tags.';
+			}
+
 			if (publishStatus === 'FAILED' && runPublish) {
 				return 'Couldn\'t publish package to npm; not pushing.';
 			}
@@ -234,7 +262,13 @@ module.exports = async (input = 'patch', options) => {
 	tasks.add({
 		title: 'Creating release draft on GitHub',
 		enabled: () => isOnGitHub === true,
-		skip: () => !options.releaseDraft,
+		skip: () => {
+			if (options.preview) {
+				return '[Preview] GitHub Releases draft will not be opened in preview mode.';
+			}
+
+			return !options.releaseDraft;
+		},
 		task: () => releaseTaskHelper(options, pkg)
 	});
 

source/npm/enable-2fa.js

@@ -4,17 +4,21 @@ const {from} = require('rxjs');
 const {catchError} = require('rxjs/operators');
 const handleNpmError = require('./handle-npm-error');
 
-const enable2fa = (packageName, options) => {
+const getEnable2faArgs = (packageName, options) => {
 	const args = ['access', '2fa-required', packageName];
 
 	if (options && options.otp) {
 		args.push('--otp', options.otp);
 	}
 
-	return execa('npm', args);
+	return args;
 };
 
+const enable2fa = (packageName, options) => execa('npm', getEnable2faArgs(packageName, options));
+
 module.exports = (task, packageName, options) =>
 	from(enable2fa(packageName, options)).pipe(
 		catchError(error => handleNpmError(error, task, otp => enable2fa(packageName, {otp})))
 	);
+
+module.exports.getEnable2faArgs = getEnable2faArgs;

source/npm/publish.js

@@ -4,7 +4,7 @@ const {from} = require('rxjs');
 const {catchError} = require('rxjs/operators');
 const handleNpmError = require('./handle-npm-error');
 
-const pkgPublish = (pkgManager, options) => {
+const getPackagePublishArguments = options => {
 	const args = ['publish'];
 
 	if (options.contents) {
@@ -23,9 +23,11 @@ const pkgPublish = (pkgManager, options) => {
 		args.push('--access', 'public');
 	}
 
-	return execa(pkgManager, args);
+	return args;
 };
 
+const pkgPublish = (pkgManager, options) => execa(pkgManager, getPackagePublishArguments(options));
+
 module.exports = (context, pkgManager, task, options) =>
 	from(pkgPublish(pkgManager, options)).pipe(
 		catchError(error => handleNpmError(error, task, otp => {
@@ -34,3 +36,5 @@ module.exports = (context, pkgManager, task, options) =>
 			return pkgPublish(pkgManager, {...options, otp});
 		}))
 	);
+
+module.exports.getPackagePublishArguments = getPackagePublishArguments;