Abstain tree from resolving in between test case.

lib/core/asynctree.js

@@ -212,6 +212,10 @@ class AsyncTree extends EventEmitter{
   }
 
   async done(err = null) {
+    if (this.currentResult instanceof Promise && !this.currentResult.settled) {
+      return err;
+    }
+
     this.emit('asynctree:finished', this);
     this.empty();
     this.createRootNode();

lib/core/queue.js

@@ -145,7 +145,8 @@ class CommandQueue extends EventEmitter {
     return Promise.resolve();
   }
 
-  run() {
+  run(result) {
+    this.tree.currentResult = result;
     if (this.tree.started) {
       return this;
     }

lib/testsuite/context.js

@@ -525,7 +525,12 @@ class Context extends EventEmitter {
       args[0] = client.api;
     }
 
-    return this.testsuite[fnName].apply(context, args);
+    const result = this.testsuite[fnName].apply(context, args);
+    if (this.currentRunnable) {
+      this.currentRunnable.currentTestCaseResult = result;
+    }
+
+    return result;
   }
 
   /**
@@ -541,7 +546,12 @@ class Context extends EventEmitter {
     const fnAsync = Utils.makeFnAsync(expectedArgs, this.testsuite[fnName], context);
     const args = this.getHookFnArgs(done, api, expectedArgs);
 
-    return fnAsync.apply(context, args);
+    const result = fnAsync.apply(context, args);
+    if (this.currentRunnable) {
+      this.currentRunnable.currentTestCaseResult = result;
+    }
+
+    return result;
   }
 
   ////////////////////////////////////////////////////////////////

lib/testsuite/runnable.js

@@ -103,8 +103,8 @@ class Runnable {
   }
 
   setDoneCallback(cb) {
-    let originalResolve = this.deffered.resolveFn;
-    let originalReject = this.deffered.rejectFn;
+    const originalResolve = this.deffered.resolveFn;
+    const originalReject = this.deffered.rejectFn;
     this.deffered.resolveFn = function() {};
     this.deffered.rejectFn = function() {};
 
@@ -159,7 +159,18 @@ class Runnable {
       }
     }
 
-    this.queue.run().then(err => {
+    if (this.currentTestCaseResult instanceof Promise) {
+      this.currentTestCaseResult
+        .catch(() => {
+          // to avoid unhandledRejections
+        })
+        .finally(() => {
+          this.currentTestCaseResult.settled = true;
+          this.queue.scheduleTraverse();
+        });
+    }
+
+    this.queue.run(this.currentTestCaseResult).then(err => {
       if (err) {
         return this.deffered.rejectFn(err);
       }