add preview flag

fixes #82

resources/extension.vsixmanifest

@@ -6,7 +6,7 @@
     <Description xml:space="preserve"><%- description %></Description>
     <Tags><%- tags %></Tags>
     <Categories><%- categories %></Categories>
-    <GalleryFlags>Public</GalleryFlags>
+    <GalleryFlags><%- flags %></GalleryFlags>
     <Properties>
       <% if (links.repository) { %>
         <Property Id="Microsoft.VisualStudio.Services.Links.Source" Value="<%- links.repository %>" />

src/manifest.ts

@@ -17,6 +17,7 @@ export interface Manifest {
 	activationEvents?: string[];
 	extensionDependencies?: string[];
 	galleryBanner?: { color?: string; theme?: string; };
+	preview?: boolean;
 	_bundling?: { [name: string]: string; }[];
 	_testing?: string;
 

src/package.ts

@@ -94,6 +94,12 @@ class MainProcessor extends BaseProcessor {
 	constructor(manifest: Manifest) {
 		super(manifest);
 
+		const flags = ['Public'];
+
+		if (manifest.preview) {
+			flags.push('Preview');
+		}
+
 		_.assign(this.vsix, {
 			id: manifest.name,
 			displayName: manifest.displayName || manifest.name,
@@ -102,6 +108,7 @@ class MainProcessor extends BaseProcessor {
 			description: manifest.description || '',
 			tags: (manifest.keywords || []).concat('vscode').join(','),
 			categories: (manifest.categories || []).join(','),
+			flags: flags.join(' '),
 			links: {
 				repository: getUrl(manifest.repository),
 				bugs: getUrl(manifest.bugs),

src/test/package.test.ts

@@ -411,6 +411,22 @@ describe('toVsixManifest', () => {
 				assert.ok(categories.some(c => c === 'world'));
 			});
 	});
+
+	it('should respect preview flag', () => {
+		const manifest = {
+			name: 'test',
+			publisher: 'mocha',
+			version: '0.0.1',
+			engines: Object.create(null),
+			preview: true
+		};
+
+		return _toVsixManifest(manifest, [])
+			.then(xml => parseXml(xml))
+			.then(result => {
+				assert.deepEqual(result.PackageManifest.Metadata[0].GalleryFlags, ['Public Preview']);
+			});
+	});
 });
 
 describe('toContentTypes', () => {