Fix #5 by properly encoding the name of scoped packages before requesting their package from npm

index.js

@@ -18,20 +18,37 @@ function get(url, cb) {
 	});
 }
 
+function getCleanName(name){
+	// Any path components in the name need to be URI encoded, however the @
+	// symbol must not be encoded.
+	// Valid URL: https://registry.npmjs.org/@sindresorhus%2Fdf/
+	// Invalid URL: https://registry.npmjs.org/%40sindresorhus%2Fdf
+	return encodeURIComponent(name).replace(/^%40/, '@');
+}
+
+function packageIsScoped(name){
+	return name[0] === '@';
+}
+
 module.exports = function (name, version, cb) {
-	var url = registryUrl(name.split('/')[0]) + name + '/';
+	var registry = registryUrl(name.split('/')[0]);
+	var url = registry + getCleanName(name) + '/';
 
 	if (typeof version !== 'string') {
 		cb = version;
 		version = '';
 	}
 
+	if (version && packageIsScoped(name)) {
+		throw new Error('Fetching a specific version of a scoped package is not allowed by npm.');
+	}
+
 	get(url + version, cb);
 };
 
 module.exports.field = function (name, field, cb) {
 	var url = registryUrl(name.split('/')[0]) +
-		'-/by-field/?key=%22' + name + '%22&field=' + field;
+		'-/by-field/?key=%22' + getCleanName(name) + '%22&field=' + field;
 
 	get(url, function (err, res) {
 		if (err) {

package.json

@@ -31,9 +31,10 @@
   ],
   "dependencies": {
     "got": "^3.2.0",
-    "registry-url": "^3.0.0"
+    "registry-url": "^3.0.3"
   },
   "devDependencies": {
+    "chai": "^3.0.0",
     "mocha": "*"
   }
 }

test.js

@@ -1,36 +1,55 @@
 'use strict';
-var assert = require('assert');
+var assert = require('chai').assert;
 var packageJson = require('./');
 
-it('should get the package.json', function (cb) {
-	packageJson('pageres', function (err, json) {
-		assert(!err, err);
-		assert.strictEqual(json.name, 'pageres');
-		cb();
-	});
-});
+function runTests(cfg){
 
-it('should get the package.json for a specific version', function (cb) {
-	packageJson('pageres', '0.1.0', function (err, json) {
-		assert(!err, err);
-		assert.strictEqual(json.version, '0.1.0');
-		cb();
+	it('should get the package.json', function (cb) {
+		packageJson(cfg.name, function (err, json) {
+			assert(!err, err);
+			assert.strictEqual(json.name, cfg.name);
+			cb();
+		});
 	});
-});
 
-it('should get the package.json main entry when no version is specified', function (cb) {
-	packageJson('pageres', function (err, json) {
-		assert(!err, err);
-		assert(json._id);
-		cb();
+	it('should get the package.json for a specific version', function (cb) {
+		if(cfg.version === 'expect-throw') {
+			assert.throws(packageJson.bind(null, cfg.name, cfg.version));
+			cb();
+		} else {
+			packageJson(cfg.name, cfg.version, function (err, json) {
+				assert(!err, err);
+				assert.strictEqual(json.version, cfg.version);
+				cb();
+			});
+		}
 	});
-});
 
-it('get a single field', function (cb) {
-	packageJson.field('pageres', 'description', function (err, res) {
-		assert(!err, err);
-		assert(typeof res === 'string');
-		assert(/screenshots/.test(res));
-		cb();
+	it('should get the package.json main entry when no version is specified', function (cb) {
+		packageJson(cfg.name, function (err, json) {
+			assert(!err, err);
+			assert(json._id);
+			cb();
+		});
 	});
+
+}
+
+// test spec
+var spec = {
+	'public packages': {
+		name: 'pageres',
+		version: '0.1.0',
+		descriptionRe: /screenshots/
+	},
+	'scoped packages': {
+		name: '@sindresorhus/df',
+		version: 'expect-throw',
+		descriptionRe: /Get free disk space info from/
+	}
+};
+
+// test runner
+Object.keys(spec).forEach(function(key){
+	describe(key, runTests.bind(null, spec[key]));
 });