Ensure that screensavers have default requirements defined

src/lib/saver-list.js

@@ -262,6 +262,10 @@ module.exports = class SaverListManager {
       contents.published = true;
     }
 
+    if ( typeof(contents.requirements) === "undefined" ) {
+      contents.requirements = ["screen"];
+    }
+
     contents.valid = typeof(contents.name) !== "undefined" &&
       typeof(contents.description) !== "undefined" &&
       contents.published === true;

src/main/index.js

@@ -635,7 +635,7 @@ var runScreenSaverOnDisplay = function(saver, s) {
   // otherwise just boot it
   //
   const reqs = saver.requirements;
-  if ( reqs.findIndex((x) => { return x === "screen"; }) > -1 ) {
+  if ( reqs !== undefined && reqs.findIndex((x) => { return x === "screen"; }) > -1 ) {
     return grabScreen(s).then((message) => {
       runSaver(message.url, saver, s, url_opts, tickCount);
     });

test/lib/saver-list.js

@@ -111,6 +111,14 @@ describe("SaverListManager", function() {
           done();
         });
     });
+
+    it("adds requirements if missing", (done) => {
+      var f = path.join(__dirname, "../fixtures/no-requirements.json");
+      savers.loadFromFile(f, false, {}).then((s) => {
+        assert.deepEqual(["screen"], s.requirements);
+        done();
+      });
+    });
   });
 
   describe("list", function() {