Milo: Increase test coverage for appengine/buildbot

milo/appengine/buildbot/builder_test.go

Index: milo/appengine/buildbot/builder_test.go
diff --git a/milo/appengine/buildbot/builder_test.go b/milo/appengine/buildbot/builder_test.go
new file mode 100644
index 0000000000000000000000000000000000000000..2f49b5d85a3587259d14e8f3c75193d8ac5ebe5d
--- /dev/null
+++ b/milo/appengine/buildbot/builder_test.go
@@ -0,0 +1,88 @@
+package buildbot
+
+import (
+	"context"
+	"testing"
+
+	"github.com/luci/gae/impl/memory"
+	"github.com/luci/gae/service/datastore"
+	"github.com/luci/luci-go/common/clock/testclock"
+	. "github.com/smartystreets/goconvey/convey"

[nodir, 2017/05/18 03:17:15]

nit: blank line before dot imports

[Ryan Tseng, 2017/05/26 18:10:52]

Done.

+)
+
+func TestBuilder(t *testing.T) {
+	c := memory.UseWithAppID(context.Background(), "dev~luci-milo")
+	c, _ = testclock.UseTime(c, testclock.TestTimeUTC)
+	fakeTime := float64(123)
+	fakeResult := int(0)
+	fakeFailure := int(2)
+
+	// Seed a builder with 8 builds.

[nodir, 2017/05/18 03:17:15]

this is 20 builds, not 8?

[Ryan Tseng, 2017/05/26 18:10:52]

Done.

+	for i := 1; i < 10; i++ {
+		datastore.Put(c, &buildbotBuild{
+			Master:      "fake",
+			Buildername: "fake",
+			Number:      i,
+			Internal:    false,
+			Times:       []*float64{&fakeTime, &fakeTime},
+			Sourcestamp: &buildbotSourceStamp{},
+			Results:     &fakeResult,
+			Finished:    true,
+		})
+		// Failed build
+		datastore.Put(c, &buildbotBuild{
+			Master:      "fake",
+			Buildername: "fake",
+			Number:      10,

[nodir, 2017/05/18 03:17:15]

are 10 builds with same number added intentionally?

[Ryan Tseng, 2017/05/26 18:10:52]

Nope, this is in the wrong indentation level.

+			Internal:    false,
+			Times:       []*float64{&fakeTime, &fakeTime},
+			Sourcestamp: &buildbotSourceStamp{},
+			Results:     &fakeFailure,
+			Finished:    true,
+			Text:        []string{"failed", "stuff"},
+		})
+	}
+	putDSMasterJSON(c, &buildbotMaster{
+		Name:     "fake",
+		Builders: map[string]*buildbotBuilder{"fake": {}},
+	}, false)
+	datastore.GetTestable(c).Consistent(true)
+	datastore.GetTestable(c).AutoIndex(true)
+	datastore.GetTestable(c).CatchupIndexes()
+	Convey(`A test Environment`, t, func() {
+
+		Convey(`Invalid builder`, func() {
+			_, err := builderImpl(c, "fake", "not real", 2, "")
+			So(err.Error(), ShouldResemble, "Cannot find builder not real in master fake.\nAvailable builders: \nfake")

[nodir, 2017/05/18 03:17:15]

this error message is hard to read. Please use %q instead of %s for
user-supplied data

[Ryan Tseng, 2017/05/26 18:10:52]

Done.

+		})
+		Convey(`Basic 3 build builder`, func() {
+			Convey(`Fetch 2`, func() {
+				response, err := builderImpl(c, "fake", "fake", 2, "")
+				So(err, ShouldBeNil)
+				So(len(response.FinishedBuilds), ShouldEqual, 2)
+				So(response.NextCursor, ShouldNotEqual, "")
+				So(response.PrevCursor, ShouldEqual, "")
+				So(response.FinishedBuilds[0].Link.Label, ShouldEqual, "#10")
+				So(response.FinishedBuilds[0].Text, ShouldResemble, []string{"failed stuff"})
+				Convey(`Fetch another 2`, func() {
+					response2, err := builderImpl(c, "fake", "fake", 2, response.NextCursor)
+					So(err, ShouldBeNil)
+					So(len(response2.FinishedBuilds), ShouldEqual, 2)
+					So(response2.PrevCursor, ShouldEqual, "EMPTY")
+					Convey(`Fetch another 2`, func() {
+						response3, err := builderImpl(c, "fake", "fake", 2, response2.NextCursor)
+						So(err, ShouldBeNil)
+						So(len(response3.FinishedBuilds), ShouldEqual, 2)
+						So(response3.PrevCursor, ShouldNotEqual, "")
+						So(response3.PrevCursor, ShouldNotEqual, "EMPTY")
+						Convey(`Fetch the rest`, func() {
+							response4, err := builderImpl(c, "fake", "fake", 20, response3.NextCursor)
+							So(err, ShouldBeNil)
+							So(len(response4.FinishedBuilds), ShouldEqual, 4)
+						})
+					})
+				})
+			})
+		})
+	})
+}