pathmgr: fix flaky unit test

[scrye]

Also make test run faster by deleting deprecated sleeps.

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This change is 

[lukedirtwalker]

Reviewed 1 of 1 files at r1.
Reviewable status: all files reviewed, 2 unresolved discussions (waiting on @scrye)

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go/lib/pathmgr/pathmgr_test.go, line 209 at r1 (raw file):

			).MinTimes(1),
		)
		pr := New(sd, Timers{ErrorRefire: getDuration(1)}, nil)

We can get rid of all timing problems I think by using a channel:

func TestWatchPolling(t *testing.T) {
	src := xtest.MustParseIA("1-ff00:0:111")
	dst := xtest.MustParseIA("1-ff00:0:110")
	Convey("Given a path manager", t, func() {
		ctrl := gomock.NewController(t)
		defer ctrl.Finish()
		sd := mock_sciond.NewMockConnector(ctrl)
		ready := make(chan struct{})
		gomock.InOrder(
			sd.EXPECT().Paths(gomock.Any(), dst, src, gomock.Any(), gomock.Any()).Return(
				buildSDAnswer(), nil,
			),
			sd.EXPECT().Paths(gomock.Any(), dst, src, gomock.Any(), gomock.Any()).DoAndReturn(
				func(_ context.Context, _, _ addr.IA, _ uint16,
					_ sciond.PathReqFlags) (*sciond.PathReply, error) {
					defer close(ready)
					return buildSDAnswer(
						"1-ff00:0:111#105 1-ff00:0:130#1002 1-ff00:0:130#1004 1-ff00:0:110#2",
					), nil
				},
			).MinTimes(1),
		)
		pr := New(sd, Timers{ErrorRefire: time.Microsecond}, nil)
		Convey("and adding a watch that retrieves zero paths", func() {
			sp, err := pr.Watch(context.Background(), src, dst)
			xtest.FailOnErr(t, err)
			Convey("there are 0 paths currently available", func() {
				So(len(sp.Load().APS), ShouldEqual, 0)
				Convey("and waiting until new paths are fetched", func() {
					<-ready
					So(len(sp.Load().APS), ShouldEqual, 1)
				})
			})
		})
	})
}

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go/lib/pathmgr/pathmgr_test.go, line 256 at r1 (raw file):

				So(len(sp.Load().APS), ShouldEqual, 0)
				Convey("and waiting for 4 time units grabs 1 path that is not filtered", func() {
					time.Sleep(getDuration(4))

Here we can probably also use the channel trick?

[lukedirtwalker]

Reviewable status: all files reviewed, 2 unresolved discussions (waiting on @scrye)

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go/lib/pathmgr/pathmgr_test.go, line 209 at r1 (raw file):

Previously, lukedirtwalker (Lukas Vogel) wrote…

We can get rid of all timing problems I think by using a channel:

func TestWatchPolling(t *testing.T) {
	src := xtest.MustParseIA("1-ff00:0:111")
	dst := xtest.MustParseIA("1-ff00:0:110")
	Convey("Given a path manager", t, func() {
		ctrl := gomock.NewController(t)
		defer ctrl.Finish()
		sd := mock_sciond.NewMockConnector(ctrl)
		ready := make(chan struct{})
		gomock.InOrder(
			sd.EXPECT().Paths(gomock.Any(), dst, src, gomock.Any(), gomock.Any()).Return(
				buildSDAnswer(), nil,
			),
			sd.EXPECT().Paths(gomock.Any(), dst, src, gomock.Any(), gomock.Any()).DoAndReturn(
				func(_ context.Context, _, _ addr.IA, _ uint16,
					_ sciond.PathReqFlags) (*sciond.PathReply, error) {
					defer close(ready)
					return buildSDAnswer(
						"1-ff00:0:111#105 1-ff00:0:130#1002 1-ff00:0:130#1004 1-ff00:0:110#2",
					), nil
				},
			).MinTimes(1),
		)
		pr := New(sd, Timers{ErrorRefire: time.Microsecond}, nil)
		Convey("and adding a watch that retrieves zero paths", func() {
			sp, err := pr.Watch(context.Background(), src, dst)
			xtest.FailOnErr(t, err)
			Convey("there are 0 paths currently available", func() {
				So(len(sp.Load().APS), ShouldEqual, 0)
				Convey("and waiting until new paths are fetched", func() {
					<-ready
					So(len(sp.Load().APS), ShouldEqual, 1)
				})
			})
		})
	})
}

The channel solution like this is also not 100% bullet proof. We could make it work with by closing the ready channel only on the second call to Paths. But as discussed offline let's go with the simple solution of using ErrorRefire: time.Microsecond and 10 or 15 ms sleep below.

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go/lib/pathmgr/pathmgr_test.go, line 256 at r1 (raw file):

Previously, lukedirtwalker (Lukas Vogel) wrote…

Here we can probably also use the channel trick?

Ditto as above.

[scrye]

Reviewable status: 0 of 1 files reviewed, 2 unresolved discussions (waiting on @lukedirtwalker)

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go/lib/pathmgr/pathmgr_test.go, line 209 at r1 (raw file):

Previously, lukedirtwalker (Lukas Vogel) wrote…

The channel solution like this is also not 100% bullet proof. We could make it work with by closing the ready channel only on the second call to Paths. But as discussed offline let's go with the simple solution of using ErrorRefire: time.Microsecond and 10 or 15 ms sleep below.

Done.

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go/lib/pathmgr/pathmgr_test.go, line 256 at r1 (raw file):

Previously, lukedirtwalker (Lukas Vogel) wrote…

Ditto as above.

Done.

[lukedirtwalker]

Reviewed 1 of 1 files at r2.
Reviewable status: complete! all files reviewed, all discussions resolved

[lukedirtwalker]

Reviewed 1 of 1 files at r3, 1 of 1 files at r4.
Reviewable status: complete! all files reviewed, all discussions resolved