Fix compatibility with some external registries

Fixes #420

Author: sindresorhus

source/npm/util.js

@@ -110,11 +110,19 @@ export const collaborators = async package_ => {
 		return stdout;
 	} catch (error) {
 		throwIfNpmTimeout(error);
+
 		// Ignore non-existing package error
 		if (error.stderr.includes('code E404')) {
 			return false;
 		}
 
+		// External registries often don't support this endpoint, so ignore errors.
+		// The whoami check is sufficient for verifying authentication.
+		// See: https://github.com/sindresorhus/np/issues/420
+		if (isExternalRegistry(package_)) {
+			return false;
+		}
+
 		throw error;
 	}
 };

test/npm/util/collaborators.js

@@ -62,11 +62,25 @@ test('non-existent', createFixture, [{
 	);
 });
 
-test('error', createFixture, [{
+test('error on default registry', createFixture, [{
 	command: accessCommand('@private/pkg'),
 	stderr: 'npm ERR! code E403\nnpm ERR! 403 403 Forbidden',
 }], async ({t, testedModule: {collaborators}}) => {
 	const {stderr} = await t.throwsAsync(collaborators({name: '@private/pkg'}));
 	t.is(stderr, 'npm ERR! code E403\nnpm ERR! 403 403 Forbidden');
 });
 
+test('error on external registry - returns false', createFixture, [{
+	command: `${accessCommand('@private/pkg')} --registry http://my-internal-registry.local`,
+	stderr: 'npm ERR! code E403\nnpm ERR! 403 403 Forbidden',
+}], async ({t, testedModule: {collaborators}}) => {
+	// Errors should return false instead of throwing, since external registries
+	// often don't support the collaborators endpoint.
+	// See: https://github.com/sindresorhus/np/issues/420
+	t.is(await collaborators({
+		name: '@private/pkg',
+		publishConfig: {
+			registry: 'http://my-internal-registry.local',
+		},
+	}), false);
+});