test(execute): try to make 'execute' test more reliable

test/integration/execute.js

@@ -27,7 +27,7 @@ const VirtualMachine = require('../../src/index');
  * been reached.
  */
 
-const whenThreadsComplete = (t, vm, timeLimit = 2000) => (
+const whenThreadsComplete = (t, vm, uri, timeLimit = 5000) =>
     // When the number of threads reaches 0 the test is expected to be complete.
     new Promise((resolve, reject) => {
         const intervalId = setInterval(() => {
@@ -44,6 +44,7 @@ const whenThreadsComplete = (t, vm, timeLimit = 2000) => (
         }, 50);
 
         const timeoutId = setTimeout(() => {
+            t.fail(`Timeout waiting for threads to complete: ${uri}`);
             reject(new Error('time limit reached'));
         }, timeLimit);
 
@@ -53,8 +54,7 @@ const whenThreadsComplete = (t, vm, timeLimit = 2000) => (
             clearInterval(intervalId);
             clearTimeout(timeoutId);
         });
-    })
+    });
-);
 
 const executeDir = path.resolve(__dirname, '../fixtures/execute');
 
@@ -127,7 +127,7 @@ fs.readdirSync(executeDir)
             // the scratch project sent us a "end" message.
             return vm.loadProject(project)
                 .then(() => vm.greenFlag())
-                .then(() => whenThreadsComplete(t, vm))
+                .then(() => whenThreadsComplete(t, vm, uri))
                 .then(() => {
                     // Setting a plan is not required but is a good idea.
                     if (!didPlan) {