Close #19 PR: add type inference option. Fixes #17

fixture.js

@@ -16,3 +16,14 @@ var cli = meow({
 Object.keys(cli.flags).forEach(function (el) {
 	console.log(el);
 });
+
+cli.stdinOrInput()
+	.then(function (input) {
+		input.forEach(function (element) {
+			console.log(element);
+		});
+	})
+	.catch(function (err) {
+		console.error(err.message);
+		process.exit(1);
+	});

index.js

@@ -8,11 +8,15 @@ var redent = require('redent');
 var readPkgUp = require('read-pkg-up');
 var loudRejection = require('loud-rejection');
 var normalizePackageData = require('normalize-package-data');
+var getStdin = require('get-stdin');
+var Promise = require('pinkie-promise');
 
 // get the uncached parent
 delete require.cache[__filename];
 var parentDir = path.dirname(module.parent.filename);
 
+global.Promise = Promise;
+
 module.exports = function (opts, minimistOpts) {
 	loudRejection();
 
@@ -25,9 +29,20 @@ module.exports = function (opts, minimistOpts) {
 			cwd: parentDir,
 			normalize: false
 		}).pkg,
-		argv: process.argv.slice(2)
+		argv: process.argv.slice(2),
+		inferType: false
 	}, opts);
 
+	minimistOpts = objectAssign({string: ['_']}, minimistOpts);
+
+	var index = minimistOpts.string.indexOf('_');
+
+	if (opts.inferType === false && index === -1) {
+		minimistOpts.string.push('_');
+	} else if (opts.inferType === true && index !== -1) {
+		minimistOpts.string.splice(index, 1);
+	}
+
 	if (Array.isArray(opts.help)) {
 		opts.help = opts.help.join('\n');
 	}
@@ -69,6 +84,19 @@ module.exports = function (opts, minimistOpts) {
 		flags: camelcaseKeys(argv),
 		pkg: pkg,
 		help: help,
-		showHelp: showHelp
+		showHelp: showHelp,
+		stdinOrInput: function () {
+			if (!_ && process.stdin.isTTY) {
+				return Promise.reject(new Error('input required'));
+			}
+
+			if (_.length > 0) {
+				return Promise.resolve(_);
+			}
+
+			return getStdin().then(function (data) {
+				return [data];
+			});
+		}
 	};
 };

package.json

@@ -39,16 +39,19 @@
   ],
   "dependencies": {
     "camelcase-keys": "^2.0.0",
+    "get-stdin": "^5.0.1",
     "loud-rejection": "^1.0.0",
     "minimist": "^1.1.3",
     "normalize-package-data": "^2.3.4",
     "object-assign": "^4.0.1",
+    "pinkie-promise": "^2.0.0",
     "read-pkg-up": "^1.0.1",
     "redent": "^1.0.0",
     "trim-newlines": "^1.0.0"
   },
   "devDependencies": {
     "ava": "*",
+    "execa": "^0.1.1",
     "indent-string": "^2.1.0",
     "xo": "*"
   }

readme.md

@@ -126,6 +126,15 @@ Default: `process.argv.slice(2)`
 
 Custom arguments object.
 
+##### inferType
+
+Type: `boolean`  
+Default: `false`
+
+Infer the argument type.
+
+By default, the argument `5` in `$ foo 5` becomes a string. Enabling this would infer it as a number.
+
 #### minimistOptions
 
 Type: `object`  

test.js

@@ -1,8 +1,11 @@
-import childProcess from 'child_process';
 import test from 'ava';
 import indentString from 'indent-string';
+import execa from 'execa';
+import pkg from './package.json';
 import fn from './';
 
+global.Promise = Promise;
+
 test('return object', t => {
 	const cli = fn({
 		argv: ['foo', '--foo-bar', '-u', 'cat'],
@@ -21,46 +24,29 @@ test('return object', t => {
 	t.is(cli.flags.unicorn, 'cat');
 	t.is(cli.pkg.name, 'meow');
 	t.is(cli.help, indentString('\nCLI app helper\n\nUsage\n  foo <input>', '  '));
-	t.end();
 });
 
 test('support help shortcut', t => {
 	const cli = fn(['unicorn', 'cat']);
 	t.is(cli.help, indentString('\nCLI app helper\n\nunicorn\ncat', '  '));
-	t.end();
 });
 
-test('spawn cli and show version', t => {
-	t.plan(2);
+test('spawn cli and show version', async t => {
+	const {stdout} = await execa('./fixture.js', ['--version']);
 
-	childProcess.execFile('./fixture.js', ['--version'], {
-		cwd: __dirname
-	}, (err, stdout) => {
-		t.ifError(err);
-		t.is(stdout.trim(), require('./package.json').version);
-	});
+	t.is(stdout, pkg.version);
 });
 
-test('spawn cli and show help screen', t => {
-	t.plan(2);
+test('spawn cli and show help screen', async t => {
+	const {stdout} = await execa('./fixture.js', ['--help']);
 
-	childProcess.execFile('./fixture.js', ['--help'], {
-		cwd: __dirname
-	}, (err, stdout) => {
-		t.ifError(err);
-		t.is(stdout, indentString('\nCustom description\n\nUsage\n  foo <input>\n', '  '));
-	});
+	t.is(stdout, indentString('\nCustom description\n\nUsage\n  foo <input>', '  '));
 });
 
-test('spawn cli and test input', t => {
-	t.plan(2);
+test('spawn cli and test input', async t => {
+	const {stdout} = await execa('./fixture.js', ['foo', '-u', 'cat']);
 
-	childProcess.execFile('./fixture.js', ['-u', 'cat'], {
-		cwd: __dirname
-	}, (err, stdout) => {
-		t.ifError(err);
-		t.is(stdout, 'u\nunicorn\nmeow\n');
-	});
+	t.is(stdout, 'u\nunicorn\nmeow\nfoo');
 });
 
 test.serial('pkg.bin as a string should work', t => {
@@ -72,10 +58,23 @@ test.serial('pkg.bin as a string should work', t => {
 	});
 
 	t.is(process.title, 'browser-sync');
-	t.end();
 });
 
 test('single character flag casing should be preserved', t => {
 	t.ok(fn({argv: ['-F']}).flags.F);
-	t.end();
+});
+
+test('type inference', t => {
+	t.is(fn({argv: ['5']}).input[0], '5');
+	t.is(fn({argv: ['5']}, {string: ['_']}).input[0], '5');
+	t.is(fn({argv: ['5'], inferType: true}).input[0], 5);
+	t.is(fn({argv: ['5'], inferType: true}, {string: ['foo']}).input[0], 5);
+});
+
+test('stdinOrInput', async t => {
+	const stdin = await execa.shell('echo \'foo bar\' | ./fixture.js');
+	const input = await execa('./fixture.js', ['foo', 'bar']);
+
+	t.is(stdin.stdout, 'meow\nfoo bar\n');
+	t.is(input.stdout, 'meow\nfoo\nbar');
 });