Moved fn skipping policy out of QueueRunner

This should allow us to more easily support complex skipping strategies
like skipping nested cleanup fns when the corresponding befores were
skipped, or skipping specs and suites when a beforeAll fails.

* #1533

spec/core/QueueRunnerSpec.js

@@ -649,6 +649,68 @@ describe('QueueRunner', function() {
     expect(nextQueueableFn.fn).toHaveBeenCalled();
   });
 
+  describe('When configured with a skip policy', function() {
+    it('instantiates the skip policy', function() {
+      const SkipPolicy = jasmine.createSpy('SkipPolicy ctor');
+      const queueableFns = [{ fn: () => {} }, { fn: () => {} }];
+      const cleanupFns = [{ fn: () => {} }];
+
+      new jasmineUnderTest.QueueRunner({
+        queueableFns,
+        cleanupFns,
+        SkipPolicy
+      });
+
+      expect(SkipPolicy).toHaveBeenCalledWith(
+        [...queueableFns, ...cleanupFns],
+        2
+      );
+    });
+
+    it('uses the skip policy to determine which fn to run next', function() {
+      const queueableFns = [
+        { fn: jasmine.createSpy('fn0') },
+        { fn: jasmine.createSpy('fn1') },
+        { fn: jasmine.createSpy('fn2').and.throwError(new Error('nope')) },
+        { fn: jasmine.createSpy('fn3') }
+      ];
+      const skipPolicy = jasmine.createSpyObj('skipPolicy', ['skipTo']);
+      skipPolicy.skipTo.and.callFake(function(lastRanIx) {
+        return lastRanIx === 0 ? 2 : lastRanIx + 1;
+      });
+      const queueRunner = new jasmineUnderTest.QueueRunner({
+        queueableFns,
+        SkipPolicy: function() {
+          return skipPolicy;
+        }
+      });
+
+      queueRunner.execute();
+
+      expect(skipPolicy.skipTo).toHaveBeenCalledWith(0, false);
+      expect(skipPolicy.skipTo).toHaveBeenCalledWith(2, true);
+      expect(queueableFns[0].fn).toHaveBeenCalled();
+      expect(queueableFns[1].fn).not.toHaveBeenCalled();
+      expect(queueableFns[2].fn).toHaveBeenCalled();
+      expect(queueableFns[3].fn).toHaveBeenCalled();
+    });
+
+    it('throws if the skip policy returns the current fn', function() {
+      const skipPolicy = { skipTo: i => i };
+      const queueableFns = [{ fn: () => {} }];
+      const queueRunner = new jasmineUnderTest.QueueRunner({
+        queueableFns,
+        SkipPolicy: function() {
+          return skipPolicy;
+        }
+      });
+
+      expect(function() {
+        queueRunner.execute();
+      }).toThrowError("Can't skip to the same queueable fn that just finished");
+    });
+  });
+
   describe('When configured to complete on first error', function() {
     it('skips to cleanup functions on the first exception', function() {
       var queueableFn = {
@@ -663,7 +725,7 @@ describe('QueueRunner', function() {
           queueableFns: [queueableFn, nextQueueableFn],
           cleanupFns: [cleanupFn],
           onComplete: onComplete,
-          completeOnFirstError: true
+          SkipPolicy: jasmineUnderTest.CompleteOnFirstErrorSkipPolicy
         });
 
       queueRunner.execute();
@@ -685,7 +747,7 @@ describe('QueueRunner', function() {
         queueRunner = new jasmineUnderTest.QueueRunner({
           queueableFns: [queueableFn],
           cleanupFns: [cleanupFn1, cleanupFn2],
-          completeOnFirstError: true
+          SkipPolicy: jasmineUnderTest.CompleteOnFirstErrorSkipPolicy
         });
 
       queueRunner.execute();
@@ -721,7 +783,7 @@ describe('QueueRunner', function() {
             },
             queueableFns: [queueableFn, nextQueueableFn],
             cleanupFns: [cleanupFn],
-            completeOnFirstError: true
+            SkipPolicy: jasmineUnderTest.CompleteOnFirstErrorSkipPolicy
           }),
           queueableFnDone;
 
@@ -744,7 +806,7 @@ describe('QueueRunner', function() {
           queueRunner = new jasmineUnderTest.QueueRunner({
             queueableFns: [queueableFn, nextQueueableFn],
             cleanupFns: [cleanupFn],
-            completeOnFirstError: true
+            SkipPolicy: jasmineUnderTest.CompleteOnFirstErrorSkipPolicy
           });
 
         queueRunner.execute();
@@ -764,7 +826,7 @@ describe('QueueRunner', function() {
           queueRunner = new jasmineUnderTest.QueueRunner({
             queueableFns: [queueableFn, nextQueueableFn],
             cleanupFns: [cleanupFn],
-            completeOnFirstError: true
+            SkipPolicy: jasmineUnderTest.CompleteOnFirstErrorSkipPolicy
           });
 
         queueRunner.execute();